Troubleshooting Procedures; H05 (Trouble In High Pressure Switch); H23 (Water Heating (For The Tank Unit) Trouble); H27 (Incorrect Water Circuit Piping Connection) - Sanyo SHP-TH90GDN-SW Technical Manual

Troubleshooting procedures

1. H05 (Trouble in high pressure switch)

This trouble is confirmed after repeated 8 retries when the refrigerant pressure has exceeded the pressure setting.
[Checkpoints]
(1) Is the circulation pump locked?
(2) Is any air trapped in the connecting pipes between the heat pump unit and tank unit?
(3) Has water been poured into the tank unit?
(4) Have you forgotten to open the tank unit's shut-off valves?
[Remedial action]
(1) Unlock the circulation pump by referring to the test run section in the heat pump unit's installation
instructions.
(2) Turn off the power and disconnect the pipes. Thoroughly purge the air from the pipes, and then re-connect
the pipes.
(3) Pour water into the tank unit.
(4) Refer to page 34 in the tank unit's Technical Manual, and open the shut off valves.

2. H23 (Water heating (for the tank unit) trouble)

[Checkpoints]
When the water temperature heated by the heat pump unit for the tank unit is too low (this kind of trouble occurs
when it is not possible to provide the circulation flow required)
(1) Is the water failing to circulate between the tank unit and heat pump unit?
(2) Is a pipe diameter too small?
When the boil-up temperature is too low (this kind of trouble occurs when the circulation flow is too high or heat
quantity is insufficient)
(3) Is a pipe whose diameter does not satisfy the rating (which is larger than the rating) being used?
(4) Have the pipes been insulated properly?
[Remedial action]
(1) Turn off the power, and replace the circulation pump.
(2)(3)Use pipes with the rated diameter and length in accordance with the installation instructions.
(4) Insulate the pipes and areas where the units are connected.

3. H27 (Incorrect water circuit piping connection)

The pipes between the heat pump unit and tank unit are crossed and connected in reverse.
[Checkpoint]
• Is the circulation pump side of the tank unit connected to the water side (B) of the heat pump unit?
[Remedial action]
• Turn off the power, close the shut-off valves of the tank unit, and change over the connecting pipes.
4. COMM ERROR (Serial communication error)
This occurs when there is a failure in the communication between the heat pump unit and tank unit.
[Checkpoints]
(1) Have both of the COMM connectors on the heat pump unit and tank unit been connected?
(2) Have both of the power connectors on the heat pump unit and tank unit been connected?
[Remedial action]
• Turn off the power, and reconnect the wires while referring to the wiring diagrams of P65 or 66.
Before replacing the heat pump unit
Be absolutely sure to check the following points before diagnosing a trouble in the refrigerant circuit.
(1) Do the outdoor temperature and current levels stand in their proper relationship? (See page 27 or 28)
(If the levels are within the reference values, there is no trouble in the closed circuits.)
(2) Is power supplied to the heat pump unit?
Is there any trouble with the thermistors? (Check the error history.) See pages 30 - 32.
(3)
(4) Is the fan running?
(5) Are the electrical wires plugged into the terminal board securely?