Time Clock Operation Patterns - Mitsubishi Electric ecodan PUHZ-W50VHA2 User Manual

Time Clock Operation Patterns

The Ecodan system incorporates hot water demand
priority this means that if there is a demand for both
modes hot water will always occur before space
heating.
Due to this the periods at which hot water and
space heating are programmed to operate are
extremely important. The hot water heat up times
should be programmed to occur during periods
when space heating is not required, this is usually the
early hours of the morning and early afternoon.
However the FTC2 system will automatically
replenish the cylinder when it falls below a certain
temperature, this is determined by DIP switch
settings SW2-1. Automatic replenishment occurs
when the immersed cylinder sensor reads a
temperature drop of either 10
Using the hot water recovery time period taken
during the commissioning stage ON and OFF times
must be programmed by the commissioning
engineer into the 2 channel time-clock, for example
if the cylinder took 1 hour to reach 55°C then the
hot water ON time should be for example 3.00am
and the OFF should be 4.15am leaving a 15 minutes
additional buffer. After this OFF time space heating
will be allowed to operate as required.
Important Note - If the hot water demand is left
ON continuous operation rather than being time-
clocked to switch OFF then the homeowner may
experience unnecessary high running costs.
Economical Time Clock Patterns & Flow
Temperatures
To gain the full benefits from the Ecodan system the
target flow temperatures and time-clock patterns
need to be configured to suit the actual property
demands.
Time clock pattern set-up
Each channel on the time clock should be programmed to meet the demands of the home occupier in the most
efficient way.
For example:
If a homeowner wakes up in the morning and wants a shower at 7am and the property takes an hour to raise
to the required room temperature then both channels should be set to 5am as the cylinder will take
approximately 1 hour to achieve temperature before switching to space heating.
heat up approximately one hour prior. This is the most efficient pattern to use rather than maintaining a high
storage temperature constantly.
The most appropriate and cost effective electricity tariff to suit the systems usage should always be sought.
COMMISSIONING
o o
C or 20 C.
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The most economical way of operating the system is
to have it running at the lowest flow temperature
possible to suit the properties thermal losses.
To do this the heating demand from the time clock
should be left constantly operational and the flow
temperatures should be reduced to a point where
the property is maintained at the design temperature
(usually 21°C) without being switched ON and OFF
clocks with night time set-back can also offer good
system efficiencies.
Important Note - If the heating demand is left on
continuous operation and
temperatures are not reduced to their lowest
possible then the homeowner may experience
unnecessarily high running costs.
Example time-clock patterns
Below is an example of a standard time clock pattern
please note this is for reference only as the inputted
times should suit the site environment and the
homeowners preferences.
Heating mode - continuous operation with reduced
flow temperatures
Hot water mode - 3.00am ON
4.15am OFF
2.00pm ON
3.15pm OFF
-day timer
the target flow
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