Troubleshooting - Craftsman CMXTEPA0018 Instruction Manual

13. Troubleshooting

Before calling for service, check the troubleshooting list of common issues.
If you are unable to resolve a problem, contact your locally authorized distributor.
PROBLEM ISSUE POSSIBLE CAUSE
No hot water and Power outage or faulty wiring. Check the power supply. Check the circuit breakers.
display do NOT
light up
The flow rate needed to
activate the heating element
(0.5 gpm) has not been
reached.
No hot water Reset the unit
and display DOES
light up
Potential internal part failure
Water is heated, The water flow rate exceeds the
but not hot heating capacity of the heater.
enough.
Voltage less than 240 Volts
Crossed Wires.
Temperature setting is too low. Increase the temperature setting on the unit.
Water pressure is less than 0.5
bar (7 psi).
Mixing too much cold water
Thermal loss due to long pipe
run.
Water is heated, Voltage less than 240 Volts
but not hot
enough.
Water is too hot. The water flow rate through
the heater is too slow.
Temperature setting is too high Switch to a lower temperature setting.
Water Temperature at faucet is
too hot.
SOLUTION
Make sure the breakers at main electrical panel are ON. You may have a faulty
breaker or unit may be wired incorrectly.
Make sure the shutoff valve on the unit's incoming water supply line is fully
open.
Increase the flow rate from the water supply source.
Clean the filter screen on the unit's water inlet.
Refer to manual (Page 18) for diagram of reset points.
Make sure to shut all power on your breaker panel before attempting to
reset unit. All resets must be pressed.
Please call us for further technical assistance.
Reduce the water flow rate at the faucet or slightly close the shutoff valve on the
unit's incoming water supply line to reduce the water flow rate.
The heating elements on your water heater are designed for 240 volts. When
used with a lower voltage, they produce less heating power. You may need to
upgrade to a larger input heater.
If it's a new installation, double check the wiring to confirm that it is correct.
Make sure the shutoff valve is fully open, and the water supply line is not
blocked.
You do not need to mix as much cold water with your tankless water heater
compared to when you use a conventional water heater. You may also have an
anti- scald feature on your faucet that is mixing cold water. These types of faucets
can usually be adjusted to reduce the amount of cold water mixed.
As the hot water from the heater runs through the hot water delivery system to
your faucet, some heat will be lost especially if it has long distance to travel or
the pipes are cold. This is normal. You can compensate for this by increasing the
setting on your water heater if you need/ want hotter water.
The computer chips in your tankless water heater are programmed with the
expectation that your incoming line voltage is 240 volts. If you have less than
240 volts [i.e. 208V or 220V], it may affect the reading on your water heater's
digital display and cause it to read slightly higher than the actual output
temperature. To compensate for this, increase the setting on your water heater if
you need or want hotter water.
Increase the flow rate at the water outlet.
Check for too little flow, or if the set point temperature is too high. This could
possibly indicate a possible internal part failure. Call us for technical assistance.
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