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Dulas Solar VC150 Handbook

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  • Page 2 CONTENTS: Page SECTION I Dulas Solar Powered VC150 Refrigerator/Freezer Installation & Operation Manual 1 to 26 …………. SECTION II Fault Finding & Repair of Photovoltaic Refrigerators 1 to 100 … …… SECTION III A User Handbook For Photovoltaic Refrigerators…………… 1 to 23...
  • Page 3 SECTION I...

  • Page 5: Table Of Contents

    CONTENTS SECTION Page No. KNOW YOUR SYSTEM Component checklist Battery safety Preparation Completed system SOLAR ARRAY Photovoltaic module assembly Support structure orientation Support structure assembly Lightning protection ELECTRICAL SYSTEM Photovoltaic controller information Photovoltaic controller installation Battery commissioning THE REFRIGERATOR/FREEZER Positioning and starting Loading Single fridge controller settings Routine maintenance...
  • Page 6 0.5m module Interconnect cable assembly Bolt, plain washer, Nylon washer, Pack Penny washer & Nut Silicon Sealant REFRIGERATOR DULAS VC150 refrigerator/ Freezer Refrigerator cable SUPPORT STRUCTURE Unirac rail Unirac high profile tilt leg kit Feet Bolt, plain washer, spring washer &...

  • Page 7: Battery Safety

    BATTERY SAFETY Observe operating instructions and position them within sight of battery! Work only on batteries under instruction of skilled personnel! The electrolyte (diluted sulphuric acid) is extremely corrosive. When working on batteries wear safety glasses and protective clothing. Acid splashes in the eyes or on the skin must be washed out or off with plenty of water.

  • Page 8: Preparation

    KNOW YOUR SYSTEM PREPARATION Before connecting, some time should be dedicated to working out all the aspects concerned in the system installation. By following these simple instructions and spending a little time on each, the whole installation process should be easier. 1) Check that all components are present, familiarize yourself with them and make sure that everything has been identified.
  • Page 9 KNOW YOUR SYSTEM COMPLETED SOLAR MODULE ARRAY SUPPORT STRUCTURE CHARGE REGULATOR BATTERY PACK REFRIGERATOR SOLAR ARRAY ACCESS GOOD VENTILATION NO DIRECT SUNLIGHT ON REFRIGERATOR...

  • Page 10: Solar Array

    SOLAR ARRAY KYOCERA MODULE ASSEMBLY PLEASE READ ALL INSTRUCTIONS THOROUGHLY BEFORE COMMENCING (FOR 12V WIRING LAYOUTS SEE ‘JUNCTION BOX WIRING DIAGRAMS’) After insuring that all the components are present, remove the solar (module a.1) from their cardboard boxes and lay them next to each other on top of the cardboard, with glass facing down.

  • Page 11: Support Structure Orientation

    SUPPORT STRUCTURE ORIENTATION The solar array must be permanently positioned where the module will receive the maximum amount of sunshine, however they are very fragile and should not be located where they may be damaged. A suitable position must be found away from trees and tall objects, to avoid shading the array, as this will impair the performance of the module.
  • Page 12 SUPPORT STRUCTURE ORIENTATION CONTINUED The support structure is made from pre-drilled galvanized steel angle. If you mounting area cannot be level e.g. you have a sloping roof, then adjusting the foot mounting holes must make the correct angle. Use the ratios below to calculate your appropriate angle and follow the diagram to position the structure accurately.
  • Page 13 SUPPORT STRUCTURE ASSEMBLY 1. Assemble the Unirac TLH High Profile tilt Legs as shown in the drawing below. The UniRac can easily be assembled in any order appropriate to the job site requirement. 2. Use 3/8” hardware to assemble the UniRac and ¼” hardware to attach the PV modules to the UniRac 3.
  • Page 14 SUPPORT STRUCTURE LOCATING MOUNTING FEET 5. The drawing below shows two options for setting the width of the Mounting feet. If possible, mount a PV module to the UniRails to determine the best attachment method for ontaining the proper distance between the mounting feet. TILT LEG 6.

  • Page 15: Lightning Protection

    LIGHTNING PROTECTION MEASURES LEVEL 1-NO PROTECTIVE MEASURES-NOT RECOMMENDED BY DULAS LTD Failure to provide protection measures against lightning strike risks damage to the equipment. In the event of lightning strike the roof mounted solar array, high voltage may be conducted towards the refrigerator system. This high voltage may damage the electronic components of the system.

  • Page 16: Photovoltaic Controller Information

    PHOTOVOLTAIC CONTROLLER INFORMATION When using Lead-Acid batteries in photovoltaic systems it is important to protect them against overcharging which would otherwise cause excessive gassing and overheating, resulting in permanent plate damage and loss of electrolyte. The Photovoltaic Controller is installed into the system to perform this task. Over –charge prevention is achieved by limiting the battery voltage to a maximum of around 2.3 Volts per cel at 25 c.This cause the charging current to fall naturally before gassing...

  • Page 17: Photovoltaic Controller Installation

    PHOTOVOLTAIC CONTROLLER INSTALLATION The unit should be installed in a dry location with clear space around it, to allow heat generated at the rear of the unit to be dissipated. The unit is fixed to the wall so that the terminals are at the bottom and the fins running vertically. Installation instructions 1.
  • Page 18 COMMISSION THE BATTERIES CONNECT THE BATTERIES THE BATTERY BOX MUST ALWAYS BE LOCATED IN A VERY WELL VENTILATED AREA AS THE BATTERIES GENERATE HYDROGEN, WHICH IS AN EXPLOSIVE GAS. 1. After choosing a final location, carefully place batteries into the empty box, ensuring not to lift by the terminal points.

  • Page 19: The Refrigerator/Freezer

    The VC150 refrigerator is designed for continuous operation, therefore an ON/OFF switch is not provided, as it is not necessary. The VC150 Freezer however, does not an ON/OFF switch to allow for defrosting? This is situated at the rear right of the...

  • Page 20: Loading

    ENERGY CONSUMPTION ONLY OPEN THE LID WHEN STRICTLY NECESSARY AND ALWAYS REPLACE INNER FOAM LIDS The VC150 refrigerator /freezer has two components, see General layout Diagram: 1) The smaller freezer (ice pack) compartment to left. 2) The larger refrigerator (vaccine) compartment to the right.

  • Page 21: Single Fridge Controller Settings

    SINGLE FRIDGE CONTROLLER The controller normally displays vaccine temperature. To see freezer temperature follow these steps: Press -the controller says hi Hold -the controller gives the high temperature (eg08) Release -the controller says Lo Hold -the controller gives the low temperature (eg03) Release -the controller says t1 Hold...

  • Page 22: Routine Maintenance 23

    ROUTINE MAINTENANCE CHECK TEMPERATURE The temperature the refrigerator should be checked each morning and afternoon. The temperature must be between 2 C and +8 C.If the temperature is not within this range then something is wrong and the vaccines will be unusable. Cnsult the W.H.O. fault finding and repair of Photovoltaic (provided with each refrigerator).
  • Page 23 ROUTINE MAINTENANCE CHECKING THE LID SEAL The lid seal is the most likely area of heat penetration. If the lid hinges are wrongly aligned or the lid seal damaged, the system will have to work harder to maintain the vaccine temperature. When the batteries run out of energy the system will fail, therefore the lid seal must be checked regularly.

  • Page 24: System Wiring Diagram

    MODULE AND BATTERY WIRING DIAGRAMS SYSTEM WIRING DIAGRAM...
  • Page 25 SYSTEM WIRING DIAGRAM GENERAL LAYOUT DIAGRAM...

  • Page 26: Electrical Circuit Diagram

    GENERAL LAYOUT DIAGRAM ELECTRICAL CIRCUIT DIAGRAM...

  • Page 27: Refrigeration Circuit Diagram

    ELECTRICAL CIRCUIT DIAGRAM REFRIGERATION CIRCUIT DIAGRAM...
  • Page 28 REFRIGERATION CIRCUIT DIAGRAM...
  • Page 29 SECTION II...
  • Page 30 WORLD HEALTH ORGANISATION EXPANDED PROGRAMME ON IMMUNIZATION FAULT FINDING & REPAIR PHOTOVOLTAIC REFRIGERATOR A TECHNICIAN’S HANDBOOK...
  • Page 31 FAULT FINDING & REPAIR OF PHOTOVOLTAIC REFRIGERATOR CONTENTS Page No. PART 1 INTRODUCTION SCOPE HOW A SOLAR PHOTOVOALTAIC REFRIFERATOR WORKS SAFETY CONSIDERATIONS PART 2: MAINTENANCE AND SERVICING WORK PREPARATION HOW TO MEASURE 1. Temperature 2. Electricity - 2.1 General - 2.2 Voltage - 2.3 Current 3.
  • Page 32 PART 3: FAULT FINDING AND REPAIR TASKS A: INTRODUCTION B: HOW TO FIND A FAULT 1. Determine the symptoms 2. Carry out Preliminary check C: FAULT FINDING CHART Chart No. Chart No. Chart No. D: FAULT FINDING AND REPAIR TASK DESCRIPTION 1.
  • Page 33 ANNEX 2. Tools and measuring Instruments PART 1: INTRODUCTION Scope This handbook is published by the World Health Organization Expanded programme on Immunization. It is general handbook for use by service and repair technicians responsible for the maintenance repair solar photovoltaic powered refrigerator.These...
  • Page 34 B: HOW A SOLAR PHOTOVOLTAIC REFRIGERATOR WORKS A photovoltaic refrigerator is similar to an ordinary compressor refrigerator except that the compressor is powered from direct current (d.c) electricity supplied from a solar array. A photovoltaic refrigerator system compries the following principal parts: The solar photovoltaic array containing solar cells, which convert sunlight into direct current (DC) electricity.
  • Page 35 C: SAFETY CONSIDERATIONS TECHNICIANS and USERS MUST ALWAYS take following precautions when transporting, handling, installing, maintaining and using photovoltaic refrigerator systems: BATTERIES BATTERIES CONTAIN ACID WHICH CAN CAUSE ACID BURNS ON SKIN OR BLINDNESS IF IN CONTACT WITH THE EYE. The acid will also damage clothes. avoid spilling or splashing battery acid especially in transport always keep the batteries upright carry batteries carefully (do not carry them on your head).
  • Page 36 SOLAR ARRAY Photovoltaic modules have a glass cover; always carry and Transport them carefully. There is a risk of receiving an electric shock from a solar array. Always take the following precautions when undertaking servicing or repair work: cover the solar array with a sheet or cloth. use insulated tools.

  • Page 37: Part 2: Maintenance And Servicing Work

    PART 2: MAINTENANCE AND SERVICING WORK A PREPARATION Before starting service or repair work make sure you are familiar with the location of the components of the solar refrigerator (see pages 37& 38) Layouts of components in some commonly used solar refrigerators are shown in Annex1.Make sure you also have the manufacturers maintenance and repair manual for the refrigerator.

  • Page 40: B: How To Measure

    HOW TO MEASURE TEMPEARTURE Temperature is measured with thermometers. There are many different types of thermometers. The choice of thermometer should depend upon the degree of accuracy, the reliability, the response rate, the temperature range required and budget available. Refrigerator and freezer temperature Temperatures are usually measured in the refrigerator and freezer compartments of photovoltaic refrigerators with low –cost, simple low precision bi-metal thermometers.

  • Page 41: Temperature

    TYPICAL REFRIGERATOR THERMOMETER BATTERY TEMPERATURE The temperature of the electrolyte in the battery cells must be measured with mercury in glass thermometer. The thermometer should have a range of not more than 0 C to 8 C;otherwise it will not be sufficiently accurate. The thermometer should be encased in a metal shell to protect it from breakage.
  • Page 43 ELECTRICITY General When doing faultfinding and repairs on photovoltaic refrigeral systems, it is necessary to measure the voltage, current and resistance at various points in the circuit. The type of voltage measured is DC (direct current) volts and no AC (Alternating current) volts as is normally observed in the electrical supply of houses.
  • Page 45 Measuring Voltage Use a millimeter or DC Voltmeter to measure DC voltage in the following manner: Set the millimeter to measure DC voltage Set the range on the meter so that it included the voltage that you expect to measure. For example, if you expect that the voltage you are going to measure will be about 12 V, set the range to 0-20V.
  • Page 46 Make sure that the meter is switched ON and that it has charged batteries inside. Some types of millimeter are switched on automatically when you turn the measurement selection knob. (a) If the meter is an analogue type as shown on this page, make sure that the needle points to 0 volts when the metal tips of the metal leads are not touching anything.
  • Page 47 MEASURING CURRENTS 2.3.1 Use a millimeter or DC ammeter to measure current in the following manner: 1. Set the millimeter to measure current. The setting on the selection knob may be labeled “current”, ”amperes”, ”amps” or just “A”. 2. Set the range so that it included the current that you expect to measure. If you expect current to be about 5A,set the range to 0-10 A.
  • Page 48 11. SWITCH THE METER OFF after you have finished taking the measurement so that you do not drain the batteries. 12. SWITCH OFF the circuit and reconnect the wire to its terminal. 13. Switch back ON the circuit.

  • Page 49: Current

    2.3.2 Using a current shunt with a millimeter or milivolt meter to measure current. Switch OFF the system. Disconnect the wire at the terminal where you want to measure the current. Select a current range that included the current yu expect to measure. Connect the shunt between the disconnected wire and the terminal and connect the probes of the millimeter to each terminal of the current shunt.

  • Page 51: Resistance

    RESISTANCE In fault finding and repairs of photovoltaic refrigerator systems it is necessary to measure the electrical resistance of the compressor windings and to determine if these windings are adequately insulated. The millimeter provided in the UNIPAC maintenance kit (or any other millimeter) is adequate for these tasks if the following procedure is observed.

  • Page 52: State Of Charge Of Batteries

    STATE OF CHARGE OF BATTERIES The amount of energy stored in a battery at any time is called the “State of Charge”. The “State of Charge” can be approximately estimated by measuring the voltage across the battery terminals when battery is being discharged under know conditions of current and temperature and is the only way to measure the State of Charge of sealed batteries.
  • Page 53 Insert the hydrometer into the electrolyte in a cell of the battery, squeeze the rubber bulb, and draw enough electrolyte into the hydrometer to make the indicator float freely. Record the specific gravity reading as indicated by the float and adjacent scale.
  • Page 54 Add this value to the reading obtained from the hydrometer. This answer gives the specific gravity of the electrolyte if at 15 degrees Centigrade. Convert the specific gravity into a measurement of the States of charge by looking at the table below. Specific gravity at 15 degrees C Vs State of charge Specific Gravity...
  • Page 55 TILT AND DIRECTION OF PHOTOVOLTAIC ARRAY General The tilt of a photovoltaic array is the angle created between the surface of the array and the horizontal. The tilt should be approximately equal to the latitude of the site, except in case where the latitude is less than 5 either North or South, in which case the tilt should be maintained at 5...
  • Page 56 HOW TO MEASURE TILT WITH A TEMPLATE AND SPIRIT LEVEL If you do not already know, find out the approximate latitude of the place where the refrigerator is installed. Cut out a triangle from cardboard if you do not plan to use it often, or from wood if you have several solar arrays to check.
  • Page 57 Place the triangle on the surface of the array so that it is parallel to the sloping sided of the array and so that the angle, which is equal to the latitude, points away from the equator. Place a spirit level on the upper edge of the triangle. If the bubble in the level indicator shows that it is level, then the photovoltaic array is set an angle, which is equal to the latitude.
  • Page 58 How to measure direction The only practical method to measure direction of the array with sufficient accuracy is with a compass. The procedure is as follows: 1. Place the cardboard or wooden template, which you used to check the tilt of the array on the surface of a module so that it is parallel to the sloping sides of the module and so that the angle on the template, which is equal to the latitude, points away from the equator.

  • Page 59: Open And Short Circuit Measurements On The Photovoltaic Array

    6: OPEN AND SHORT CIRCUIT MEASUREMENTS ON THE PHOTOVOLTAIC ARRAY Two simple measurements are possible to show whether a photovoltaic array is prating correctly. These are the measurement of SHORT CIRCUIT CURRENT AND OPEN CIRCUIT VOLTAGE. Measurements are made as follows: Using a millimeter or voltmeter to measure open-circuit voltage (Voc) To test the solar array or one of the solar module in the array, you need to be able to measure the open-circuit voltage (Voc).
  • Page 60 Using a millimeter or ammeter short-circuit current (Isc) To test solar array or one of the modules you need to be able to measure the short-circuit current (Isc). Measure Isc around 12 noon on a very clear sunny days and during a long period of uninterrupted sunshine (no clouds).

  • Page 61: Introduction

    MAINTENANCE AND SERVICE TASKS Introduction The service tasks described here should all be done every time you visit a solar refrigerator. BEFORE YOU START THE SERVICE TASKS DO THE FOLLOWING: a) Check that the temperature of the refrigerator is normal (between+0 C and +8 before you start the service.

  • Page 62: Cleaning The Solar Array

    C.2. Cleaning the Solar Array You should clean the surface of the solar array whenever you visit the health post. Clean the array in the early morning or in the evening when it is not in strong sunlight. If the solar array is on the roof you will need a ladder to reach it. Be very careful when working on the roof.

  • Page 63: Preventing Solar Array Shadowing

    Preventing Solar Array Shadowing The solar array will not work properly if it is shaded during the day. Check that the solar array is not shaded on any part. This should be checked at approximately 8.00 a.m., 12.00 noon, and 4.00 p.m. on the day that you visit the health centre.

  • Page 64: Inspection Of Electrical Cables

    Inspection of Electric Cables Electric cables run between the charge regulator and the solar array, the batteries, and the refrigerator. These cables should be inspected every time you visit an installation to make sure that they are in good condition. Check the connections on the cables, which go to the battery terminals, the solar array terminals, the refrigerator terminals (on the compressor controller and on the refrigerator socket), and the charges regulator terminals strip.

  • Page 65: Checking The Performance Of The Solar Array

    Checking the Performance of the Solar Array NOTE 1: It is only necessary to check the performance of the solar array if you believe there may be problem with it. For example if the user reports or the daily record sheets indicate that the “Do not freeze Ice Packs” or “Refrigerator Disconnected”...

  • Page 66: Battery Maintenance

    Battery Maintenance Warning: ● KEEP NAKED FLAMES AWAY FROM BATTERIES AS EXPLOSIVE GASES MAY BE PRESENT. ● THE LIQUID IN BATTERIES IS CORROSIVE. KEEP OUT OF SKIN AND AWAY FROM EYES.AVOID CONTACT WITH CLOTHES. Switch the refrigerator OFF. Disconnect the battery cables at the battery labeling the cables clearly so you know where to reconnect them.
  • Page 67 If there are non-sealed batteries, measure and note in the log book the electrolyte specific gravities and temperatures and determine the state of charge of the batteries (see page no 46) Check the ages of the batteries from the logbook or from marks on them. If they are more than 5 years old, order and fit a replacement as soon as possible.

  • Page 68: Defrosting The Refrigerator

    Defrosting the Refrigerator If the ice in the freezer compartment of the refrigerator is more than 5 mm (1/4 inch) thick, defrost the refrigerator. (a) Move the vaccine into another refrigerator or store it in a cold box with ice-packs. (b) Switch the refrigerator OFF.
  • Page 69 Cleaning the Refrigerator (a) Switch off the refrigerator. (b) Clean the surfaces of the condenser and compressor using a soft brush. The condenser and compressor must be clean or the refrigerator will not work properly. (c) If the condenser is fan-assisted make sure the fan rotates freely and brush dirt away from the fan and fan motor.
  • Page 70 PART 3: FAULT FINDING AND REPAIR A.1. INTRODUCTION (a) Before starting the fault finding, make sure you are familiar with the location of the components of a solar refrigerator. A typical solar refrigerator is layout is shown on pages 37 & 38 Annex 1 shows the location of components on the most commonly used solar refrigerator.

  • Page 71: B: How To Find A Fault

    HOW TO FIND FAULT The instructions in this part of the handbook advise you on what to do if the refrigerator compartments are not maintaining the correct internal temperatures. The temperatures should be more than 0 C and less than 8 C in the refrigerator compartments, and less than 0 C in the freezer compartment.
  • Page 72 SYMPTOM- The refrigerator is too warm (above 8 C) and the compressor is NOT running. Check that it is switched ON. If not, then switch it ON. Do ALL the USER maintenance checks listed on pages 65 to 67 Check that someone has NOT changed the thermostat setting to a warmer setting.

  • Page 73: C: Fault Finding Chart

    FAULT FINDING CHART CHART NO.1 SYMPTOM - Refrigerator is too WARM and compressor is NOT running. Check out the following possible faults by first looking at the fault at the top of the chart. If this is found not to be the fault then move to the next fault in the direction of the arrows.

  • Page 74: System Sizing

    CHART NO. 2 SYMPTOM-Refrigerator is TOO WARM (above 8 C) and the compressor is running at times. Check out the following possible faults by first looking at the fault at the top of the chart. If this is found not to be the fault then move to the next fault in the direction of the arrows.
  • Page 75 CHART NO. 3 3 SYMPTOM-Refrigerator is TOO COLD Remember –VACCINE IS DESTROYED IF FROZEN Check for the following possible faults by first looking at the top of the chart. If this is found not to be the fault then move to the next fault in the direction of the arrows. Possible fault Fault finding &...
  • Page 76 D FAULT FINDING AND REPAIR TASKS DESCRIPTIONS D.1. USER MAINTENANCE TASKS The user is responsible for undertaking routine maintenance tasks. If the refrigerator stops operating correctly, the user is also trained to do simple checks before calling for the solar refrigerator technician. IT IS YOUR RESPONSIBILITY TO: ●...
  • Page 77 If it is necessary to replace the seal or adjust the door, check afterwards that the contact between the lid/door and the refrigerator cabinet is good. (f) Check that: ● The condenser and compressor are free from dust. ● that the fan (if fitted) turns freely, and ●...
  • Page 78 ● if the level of water in any cell has ever dropped below the op of the metal plates. ● where he obtains his distilled water, and how often. ● what the distilled water is stored in, and how is the container closed. This information will help you determine if the batteries are in good condition.
  • Page 79 D.2. FAULTY THERMOSTAT 2.1 REFRIGERATOR IS TOO COLD (COLDER THAN 0 SYMPTOMS OF THE FAULT The refrigerator compartment is too cold. The compressor MAY run all the times HOW TO CONFIRM THIS FAULT 1.Check the evaporator is adequately defrosted. 2. Check the thermostat-sensing element is firmly attached. (In some refrigerator it is attached to the evaporator) 3.
  • Page 80 2.2 REFRIGERATOR TOO WARM (Warmer than 8 SYMPTOMS OF THE FAULT 1.The refrigerator compartment is too warm. 2.the compressor MAY not be running or running Only very occasionally Hoe to confirm this fault 1. Check the evaporator is adequately defrosted. If it is not this may be the problem. Defrost the refrigerator.
  • Page 81 9. If the compressor runs when you connect the temporary wire, but do not run with this temporary wire then: - The thermostat is faulty or - The wires are incorrectly connected or - The wires are defective Repair Action required 1.Tighten, correct or change the wires.
  • Page 82 D.3. FUSE BLOWN IN COMPRESSOR CONTROLLER SYMPTOMS OF THE FAULT 1.The refrigerator is TOO warm AND THE COMPRESSOR IS NOT RUNNING 2.REFRIGERATION DISCONNECTED indicator light may be lit. How to confirm this fault 1.Switch off the regulator. 2.Remove fuse from the compressor controller. Check that the fuse holder is not corroded and that the fuse fits tightly in the fuse holder.
  • Page 83 5 Disconnect at the compressor controller the wires from the thermostat and fan (if fitted). Fit a temporary wire between terminals T and C of the compressor controller. 6.Replace the fuse with a good fuse of the correct type and switch on the refrigerator.
  • Page 84 D4.FUSE BLOWN IN CHARGE REGULATION SYMPTOMS OF THE FAULT The refrigerator is TOO WARM and the compressor is not running. HOW TO CONFIRM THIS FAULT SOME TYPES OF CHARGE REGULATOR DO NOT HAVE FUSES in the charge regulator, if this is the case then proceed to the next step on FAULT FINDING CHART no.1 If the charge regulator is fitted with a fuse then 1.Switch off the refrigerator...
  • Page 85 4. Check that the batteries are connected with the correct polarity to the charge regulator and that any other connections are correct, tight and not corroded. 5.Fit a fuse tested to be good and of the correct size. 6. Switch on the refrigerator. (Some models also have circuit breaker protecting the refrigerator, make sure that it is also switched on.) 7.Turn off the refrigerator, take out the fuse and check it.
  • Page 86 D5: LOW STATE OF CHARGE OF BATTERIES THE BATTERIES MAY BE FAULTY OR MAY ONLY HAVE A LOW STATE OF CHARGE as a result of a long period of cloddy weather. SYMPTOMS OF THE FAULT 1 The refrigerator is too warm. 2 The voltmeter (not fitted to all models) shows battery voltage to be less than 11.5 3.THE REFRIGERATOR DISCONNECTED indicator light is lit of has lit recently.
  • Page 87 With the solar array still covered, switch ON the refrigerator. THE REFRIGERATOR COMPRESSOR SHOULD NOW RUN. If the COMPRESSOR DOES NOT RUN PROCEED TO THE NEXT STEP ON THE FAULT FINDING CHART. If the COMPRESSOR DOES NOT RUN: Check the level of distilled water in each cell of each battery, and top up water if necessary (see page 57) Recharge each battery (unless battery manufacturer or supplier states this is not to be done for your batteries)
  • Page 88 D6. WIRING SYMPTOMS OF THE FAULT 1. The refrigerator is too warm and the compressor is not running. 2.The refrigerator operates normally sometimes but at other times the refrigerator Is too warm and the compressor is not running. How to confirm this fault 1.
  • Page 89 6. Check the voltage at the charge regulator and compressor controller again as detailed above under” How to confirm this fault.” If the voltages are now correct the faults has been repaired. If the voltage is still not correct PROCEED WITH THE NEXT CHECK ON THE FAULT FINDING CHART.
  • Page 90 D.7 PHOTOVOLTAIC ARRAY SYMPTOMS OF THE FAULT 1. The refrigerator is too warm and the compressor is not running or is running only very occasionally. 2. The Batteries become discharge periodically. 3. The indicator lights for normal operations my not be lit or the “Refrigerator Disconnected”...
  • Page 91 8.If the solar array short circuit current or open current voltage does not appear correct then there may be a fault with a module or the way the modules are connected together. 9.Measure the open circuit voltage and short circuit current in each module with each module disconnected from the other modules.
  • Page 92 D.8 COMPRESSOR CONTROLLER SYMPTOMS OF THE FAULT The refrigerator is too warm and the compressor does not run How to Confirm this fault Measure the voltage at the input terminals of the compressor controller. If the voltage is more than 11.5 volts (12 volt system) or more than 22.5 volts (24 volts system) the compressor should run.
  • Page 93 D.9 CHARGE REFULATOR FAULTY SYMPTOMS OF THE FAULT 1. The refrigerator is too warm and the compressor is not running only occasionally. 2.The batteries become discharged periodically. How to confirm this fault 1. If all previous steps in the faultfinding procedures have not indicated a fault then change the charge regulator (see page 84) and see if the refrigerator operates normally for at least one month.
  • Page 94 D.10 CONDENSER FAN (If fitted) SYMPTOMS OF THE FAULT The refrigerator is too warm and the compressor is a not run very frequently. How to confirm this fault When the compressor is running look to see if the condenser fan is rotating. If it is rotating this is not the problem.
  • Page 95 D.11. COOLING CIRCUIT FAULT SYMPTOMS OF THE FAULT The refrigerator is too warm and the compressor is a not run continuously or very frequently. How to confirm this fault 1. If the compressor runs and the evaporator plate do not get cold all over then: (a) The cooling circuit may be undercharged with refrigerant, or (b) The capillary tube blocked, or (c) There may be moisture in the system...
  • Page 96 D.12 COMPRESSOR SYMPTOMS OF THE FAULT The refrigerator is too warm. How to confirm this fault 1. Measure the Voltage at the input terminals of the compressor controller. If the voltage is more than 11.5 volts (12 volt system) or more than 22.5 volts (24 volts system), the compressor should run.
  • Page 97 Repair action required 1. ONLY CHANGE COMPRESSOR WHEN YOU ARE SURE THAT ALL PREVIOUS STEPS IN THE FINDING CHART HAVE BEEN CAREFULLY CHECKED. Replace the compressor in accordance with the manufacturers instructions, Refer also to the procedure described in the WHO handbook for COMPRESSION refrigerator repairs.
  • Page 98 D.13 SYSTEM SIZING SYMPTOMS OF THE FAULT 1. Refrigerator operates correctly during certain seasons, but the battery becomes discharged at times in the year when it is not very sunny or the ambient temperature is high. 2. The indicator light “Do NOT Freeze Icepacks” and possibly “Refrigerator Disconnected”...
  • Page 99 5. If the above checks indicate that the refrigerator is being correctly operated and that no parts of the system are defective, then closely observe the operation of the refrigerator during several days and note when the indicator lights shows “Do Not Freeze Icepacks”...

  • Page 100: Introduction

    E. REPAIR TECHNIQUES E.1 INTRODUCTION Some of the repair tasks that you may have to carry out on the cooling system of a solar powered refrigerator are similar to those for a normal compression refrigerator. These have been fully described in the Technicians Handbook for compression refrigerators Parts A, B and C, produced by WHO Expanded Programme on Immunization.
  • Page 101 E.2 REPLACING A MODULE OF THE SOLAR ARRAY (a) Work on the solar array early in the morning or in the evening. Completely cover the front of the solar array with thick cloth or a sheet. The solar array must not be in bright sunshine when you work on it except when you are checking performance.
  • Page 102 Connect the module cables to the correct terminals in the module terminal box. Replace the lid of the module terminal box. Do not over tighten the lid screws. Reconnect the solar array back to the charge regulator at the charge regulator terminal strip.
  • Page 103 E.3 ADJUSTING THE THERMOSTAT (a) Set the thermostat in its middle position (halfway between its maximum and minimum settings). Allow 4 hours for the temperature to stabilize. (b) Read the thermostat in the bottom of the refrigerator compartment after 4 hours. The temperature should be 2 C and 4 (c) If it is not, adjust the thermostat to a warmer or colder setting as appropriate.
  • Page 104 E.4. REPLACING POWER CABLES (a) The power cables are electrical wires running from the charge regulator to the solar array, the batteries and the refrigerator. (b) If one of these cables is damaged it must be replaced because it might cause a short-circuit.
  • Page 105 E.5 REPLACING THE CHARGE REGULATOR (a) Switch the refrigerator OFF. If the charge regulator has an ON/OFF switch the charge regulator OFF too. (b) Cover the solar array with a thick cloth or a sheet. Make sure that the array is completely covered and be careful not to scratch its surface.
  • Page 106 (c) If you cannot cover the solar array, replace the voltage regulator early in the morning or in the evening when the Sun is low in the sky. (d) LABEL ALL WIRES what you are about to disconnect so that you can reconnect them to the correct points.
  • Page 107 E.6 REPLACING THE COMPRESSOR CONTROLLER The compressor controller is fitted to the electrical circuit to reduce the possibility of damage to the compressor motor. If it is faulty, it should be replaced as follows: Switch the refrigerator OFF. Disconnect the wires from the battery terminals. Label all the wires you are about to disconnect.
  • Page 108 (g) Reconnect all wiring to the compressor controller (ensuring correct polarity) in the reverse order they were disconnected. (h) Reconnect the wires to the battery terminals. (I) Switch the refrigerator ON again.
  • Page 109 E.7 REPLACING THE CONDENSER FAN (If fitted) The refrigerator may have a small fan that blow airs onto the condenser tubing too help keep it cool. If there is condenser fan and it is broken, replace it according to the following instructions: Switch the refrigerator OFF Disconnect the battery (or batteries)
  • Page 110 E.8 REPLACING A BATTERY (a) Switch the refrigerator OFF. (b) Mark which wire goes to the positive terminal and which wire goes to the negative terminal (c) Disconnect the wires of the faulty battery at the battery terminals. (d) Remove the faulty battery and replace it with a new one. The battery must be of the same type as the old one.
  • Page 111 PART 4: RECORD KEPING 1. INTRODUCTION Record keeping is a very important activity because: It provided the repair technician with important information needed for repair work; It provides cold chain management with statistics which assist in project evaluation and future project planning; It permits better care of vaccines and reduces waste;...
  • Page 112 DAILY RECORD SHEET Week from TIME QUANTITIES LOADED TEMPERATURE IN ABMIENT INDICATION SIGNAT REFRIGERATOR TEMPERATURE COMPARTMENT VACCINES PACKS MORNING MONDAY AFTERNOON MORNING TUESDAY AFTERNOON MORNING WEDNESDAY AFTERNOON MORNING THURSDAY AFTERNOON MORNING FRIDAY AFTERNOO MORNING SATURDAY AFTERNOO MORNING SUNDAY AFTERNOO...
  • Page 113 MAINTENANCE RECORD SHEET SIDE 1 NAME OF SITE: MAKE AND MODEL OF REFRIGERATOR: QUANTITY AND TYPE OF BATTERIES: QUANTITY AND TYPE OF PV MODULES: POSSIBLE FAULT RESULT OF FAULT FINDING CHECK...
  • Page 114 MAINTENANCE RECORD SHEET SIDE 2 DESCRIPTION OF REPAIR MODE PARTS USED NAME OF PART QUANTITY PART NUMBER CHECKED PERFORMED AFTER THE REPAIR NAME OF PART CHECKED RESULT OF CHECK DATE OF REPAIR: NAME OF REPAIR TECHNICIAN: SIGNATURE OF REPAIR TECHNICIAN SIGNATURE OF RESPONSIBLE PERSON AT SITE:...
  • Page 115 2. Completing the maintenance record sheet The procedure to fill in a MAINTENANCE RECORD SHEET is very easy. The steps are as follows At the top of the first page: 1. Write the name of the site in the space provided. 2.
  • Page 116 10. In the space provided under ACTION, describe the repair and give a complete lists of the parts used. including part numbers if possible. 11. Following the repair, check that the component that you have replaced is operating correctly by repeating the “How to Confirm a Fault” for the step where the repair was performed.
  • Page 117 PART 5 USER TRAINING The installation technician initially does user training when the refrigeration system is installed. The installation technician explains the activities described in the USER HANDBOOK FOR PHOTOVOLTAIC REFRIGERATOR. As the repair technician you are responsible for continuing the training of the user of the photovoltaic refrigerator system.
  • Page 118 B HOW TO OPERATE THE SYSTEM The user should fully understand how to operate system. This is described in detail in PART 2-HOW TO OPERATE YOUR SYSTEM OF THE USER HANDBOOK FOR PHOTOVOLTAIC REFRIGERATOR. Check that the user understands. How to switch the refrigerator ON. Opening and closing of the refrigerator cabinet.
  • Page 119 The tasks you should check the user can do are as follows: Group 1(tasks normally done daily by the users) 1. Fill in the DAILY RECORD SHEET. 2. Check the indicator lights and any other meters. 3. Check that there is free air circulation all around and underneath the refrigerator cabinet.
  • Page 120 WHAT TO DO IF A FAULT OCCURS The user should know what to do if a fault occurs. This is described in detail in “Part 4- what to do if a Fault occurs” of the USER HANDBOOK FOR PHOTOVOLTAIC POWERED REFRIGERATOR. Part 4 defines a procedure which the user should follow if a fault occurs, it is important that this procedure be fully understood.
  • Page 121 GLOSSARY OF TECHNICAL TERMS BATTERIES Store the electricity to supply the SOLAR PHOTOVOLTAIC at night and in cloudy weather when there is no sunshine. CHARGE REGULATOR An electronic unit that regulates the amount of electricity being put into the BATTERIES. It prevents over charging and damage to the BATTERIES.
  • Page 122 FREEZER COMPARTMENTS The coldest compartment of the REFRIGERATOR, usually with its own separate door inside the main door. ICEPACKS are frozen inside the FREEZER COMPARTMENT. FUSE A small strip of metal (in a holder) that melts when there is too much electricity consumed .A FUSE protects electrical components from damage.
  • Page 123 SERVICE AND REPAIR The person who visits the health post to TECHNICIAN carry out regular preventative maintenance SOLAR PHOTOVOLTAIC REFRIGERATOR and any repairs the are necessary SOLAR ARRAY Produces electricity when sunlight falls on it. Often referred to as the PV ARRAY. SOLAR PHOTOVOLTAIC REFRIGERATOR supplied...
  • Page 124 ANNEX 1 COMPONENT LAYOUTS OF SOME COMMONLY USED SOLAR REFRIGERATOR...
  • Page 130 ANNEX II ADDITIONAL EPI TOOL KIT NEEDED FOR PHOTOVOLTAIC REFRIGERATOR REPAIR...
  • Page 131 ADDITIONAL TOOLS REQUIRED TO THE STANDARD UNIPAC/EPI TOOL KIT -Millimeter (digital) ●10 Amp ● 10 mV accuracy ● Ohm - 2 shunts - ● 0-200 mV at 0-20 Amps - 1 hydrometer, break proof - 1 compass - 1 pair of plastic gloves - 1 spirit level - 1 latitude template (to manufacture on site) - 1 mercury in glass thermometer-range 10-60...
  • Page 132 DULAS limited SECTION III SYSTEM HANDBOOK WORLD HEALTH ORGANISATION A USER HANDBOOK PHOTOVOLTAIC REFRIGERATOR DULAS LTD. Dyfi Eco Parc Machynlleth, Powys, WALES’s SY20 8AX U.K. Tel +44(0) 1654 705000 Fax +44(0) 1654 703000 E-mail: solar@dulas.org.uk Website: www.dulas.org.uk...
  • Page 133 A USER HANDBOOK PHOTOVOLTAIC POWERED REFRIGERATOR CONTENTS Page No. SCOPE 1. ACTION ON HANDOVER Table 1. Ask the installation technician to provide you With the following information Table 2. Site Data Sheet Table 3 Example of Daily record sheet Table 4 Is the installation correct Table 5 Is the Photovoltaic Refrigerator system Operating correctly 2.

  • Page 134: Scope

    SCOPE The World Health Organization Expanded Programme on Immunization has published this handbook. It is a handbook for users of stand-alone, photovoltaic powered compression refrigerators operating at 12 V or 24 V DC in medical centers. These refrigerators are used for storing vaccines and medicine and for freezing icepacks. Stand-alone means here that the solar array does not power any other device (e.g.

  • Page 135: Action On Handover

    ACTION ON HANDOVER You should read this section before the installation technicians have left the health centre. There are some important questions that you must ask them before they go. Getting to know your solar refrigerator Your new solar refrigerator is an important part of the cold chain. You can store vaccine and medicine in it safely, and freeze icepacks in the freezer compartment.
  • Page 138 Tables 1 ASK THE INSTALLATION TECHNICIAN TO PROVIDE YOU WITH THE FOLLOWING INFORMATION AND WRITE IT DOWN ON THIS PAGE. Maximum number of icepacks to be Placed in the freezer in any one day:………………………………….. Vaccines capacity of Refrigerator compartment: ……………………………………liters 3 The Model of the Refrigerator…………………………………………...
  • Page 139 Table 2 SITE DATA SHEET (TO BE COMPLETED AND SIGNED BY THE TECHNICIAN AND USER) 1. Full Address of Health Centre:……………………………………………. …………………………………………………………………………….. …………………………………………………………………………….. 2. Name and rank of person Responsible for centre:……………………………………………………. …………………………………………………………………………….. ……………………………………………………………………………. Names of centers Staff trained To use and do user level Maintenance on system……………………………………………………...
  • Page 140 10. List of tools, manuals, record sheets and supplies provided for user (tick and indicate quantity id supplied) Daily Record Sheets……………………………………………….. 10 fuses for each place……………………………………………… Distilled water in closed container…………………………………. Talcum powder…………………………………………………….. Flat-bladed screwdriver……………………………………………. Phillips screwdriver………………………………………………… Soft brush to clean condenser………………………………………. Sponge to clean Array……………………………………………..
  • Page 141 Table 3 EXAMPLE OF DAILY RECORD SHEET DAILY RECORD SHEET Week from QUANTITIES LOADED TEMPERATURE IN ABMIENT INDICATION TIME REFRIGERATOR SIGNATURE TEMPERATURE COMPARTMENT ICEPACKS VACCINES MORNING MONDAY AFTERNOON MORNING TUESDAY AFTERNOON MORNING WEDNESDAY AFTERNOON MORNING THURSDAY AFTERNOON MORNING FRIDAY AFTERNOON MORNING SATURDAY AFTERNOON...
  • Page 142 Table 4 IS THE INSTALLATION CORRECT? The Solar Array: Can you reach it easily and safely to clean it? Is it protected so that unauthorized persons cannot damage it? Are the cables, which are connected to the array firmly attached of, hidden? The Refrigerator Cabinet: Is there good air circulation around all sides and on top of the Refrigerator cabinets especially in front of the ventilation grill?
  • Page 143 Table 5 IS THE PHOTOVOLTAIC REFRIGERATOR SYSTEM OPERATING CORRECTLY? Does the refrigerator cabinet LID close properly? Is the THERMOMETER in the refrigerator cabinet showing temperature of more than 0 C and less tan 8 Are the INDICATOR LIGHT showing that ICE PACKS MAY BE FROZEN? Does the COMPRESSOR start and stop periodically? IF THE ANSWER TO ALL QUESTIONS IS YES...

  • Page 144: How To Operate Your System

    2 HOW TO OPERATE YOUR SYSTEM 2.1 General Remarks The refrigerator must always be turned on during normal use. Only open the refrigerator cabinet when it is necessary. Make sure that you close it quickly and securely. Always lock the refrigerator cabinet immediately after use. Only turn the refrigerator OFF when: 0 you need to defrost the evaporator 0 you need to change a fuse...

  • Page 145: Loading The Refrigerator

    2.2 Loading the Refrigerator (a) DO NOT LOAD icepacks if the “DO NOT FREEZE ICEPACK” indicator light is on. (b) LOAD the freezer compartment with ICE PACKS IN THE MORNING ONLY. (c) Do not put more than the recommended amount of icepacks in the freezer compartment in any one-day (d) Do not put more than the recommended amount of vaccine in the refrigerator compartment...

  • Page 146: Filling In The Daily Record Sheet

    Filling in the DAILY RECORD SHEET Look at the TIME and Write this down in the correct row in your DAILY RECORD SHEET. The record sheet shows the day of week and whether the entry you are making is a morning or afternoon recording. Choose the correct row to make your entry.

  • Page 147: User Maintenance

    USER MAINTENANCE Daily tasks Fill in the DAILY RECORD SHEET each morning and afternoon. The refrigerator compartment temperature must be more than 0 C and less than C.If the temperature is not correct, then to go section 4 of this handbook “WHAT TO DO IF A FAULT OCCURS”...

  • Page 148: Weekly Tasks

    3.2 Weekly tasks Check the amount of ice forming around the freezer compartment .it is normal for a little ice to from in the freezer, but if the ice is thicker than 5mm(1/4 inch) then move the vaccine to another refrigerator or store it in a cold box with ice packs. The refrigerator must be switched off, and the refrigerator cabinet defrosted.
  • Page 149 Clean the solar array. Dust and Dirt on the solar array reduces its capacity to produce electricity. It should always be kept clean. The proper steps for CLEANING THE SOLAR ARRAY are as follows: (I) Remember- always cleans in the early morning or evening when the solar array is not in strong sunlight to avoid risk of damage.

  • Page 150: Monthly Tasks

    3.3Monthly tasks Clean the parts of the refrigerator cabinet. To Operate correctly and reliably, the refrigerator cabinet and the parts inside it must remain clean. The proper steps for CLEANING THE PARTS OF THE REFRIGERATOR CABINET are as follows: (I) Switch OFF the refrigerator. (ii) Remove or open the Cover which provided access to the compressor, condenser and fan (if fitted) of the refrigerator cabinet.
  • Page 151 Check for shadowing of the array Shading of the array, even partly will reduce the amount of electricity produced for the refrigerator. Check that the Solar array is not shaded during hours of sunlight. This should be checked at approximately 8 am, 12 noon and 4 pm .The following action is necessary if you find that any part of array is shaded during normal sunlight hours: (I) Cut back bushes and trees that may have started to shade the solar array...

  • Page 152: Six-Monthly Tasks

    3.4Six-Monthly tasks Check level of acid in all types of batteries, which are sealed. If the level of the electrolyte (acid mixture) in any of the cells in the batteries drops sufficiently to expose the plates of the battery, then the battery will be damaged and the refrigerator will not operate properly.
  • Page 153 (I) If the batteries are not of the sealed type, then they will have plastic stoppers or a plastic lid on the top. Remove each stopper or each lid one by one and see if the metal plates inside are covered by liquid. There is often a mark on indicator, which shows the correct level.
  • Page 154 (c) Check the lid/door seal. If the seal does not prevent the cold inside the refrigerator and freezer compartments from escaping into the room when the door/lid is closed. Then your refrigerator will require more electricity to run and the refrigerator system will not operate correctly.

  • Page 155: What To Do If A Fault Occurs

    WHAT TO DO IF A FAULT OCCURS. DO THE FOLLOWING First, identify the symptoms of the fault by finding out if: The refrigerator is too warm (above 8 C) and the compressor is NOT running. You may determine if the compressor is running by: Listening for the motor noise from the compressor Touching the compressor to see if it is vibrating Touching the compressor to see if it is warm.
  • Page 156 4.1 The refrigerator is too warm (above 8 C) and the compressor is NOT RUNNING. Check that it is switched ON. If not, then switch it ON. DO ALL the user maintenance tasks defined in Section 3 of this manual. Check that the thermostat setting has NOT been changed if the model fitted to your refrigerator can be adjusted.

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