installation manual

T

ROUBLESHOOTING

This section provides useful information for diagnosing and correcting certain troubles which may occur in the unit.

General guidelines

Before starting the troubleshooting procedure, carry out a thorough visual inspection of the unit and look for obvious defects such as loose connections or defective wiring.

Before contacting your local dealer, read this chapter carefully, it will save you time and money.

When carrying out an inspection on the switch box of the unit, always make sure that the main switch of the unit is switched off.

When a safety device was activated, stop the unit and find out why the safety device was activated before resetting it. Under no circumstances safety devices may be bridged or changed to a value other than the factory setting. If the cause of the problem cannot be found, call your local dealer

.

If the pressure relief valve is not working correctly and is to be replaced, always reconnect the flexible hose attached to the pressure relief valve, to avoid water dripping out of the unit!

NOTE

For problems related to the optional solar kit for domestic water heating, refer to the troubleshooting in the installation manual of that kit.

General symptoms

Symptom 1: The unit is turned on (

y

LED is lit) but the unit is not heating or cooling as expected

P

OSSIBLE CAUSES

The temperature setting is not correct.

The water flow is too low.

C

ORRECTIVE ACTION

Check the controller set point.

The water volume in the installation is too low.

• Check that all shut off valves of the water circuit are completely open.

• Check if the water filter needs cleaning.

• Make sure there is no air in the system (purge air).

• Check on the manometer that there is sufficient water pressure. The water pressure must be >0.3 bar

(water is cold), >>0.3 bar (water is hot).

• Check that the pump speed setting is on the highest speed.

• Make sure that the expansion vessel is not broken.

• Check that the resistance in the water circuit is not too high for the pump (refer to

"Setting the pump speed" on page 16 ).

Make sure that the water volume in the installation is above the minimum required value (refer to

"Checking the water volume and expansion vessel pre-pressure" on page 10

).

Symptom 2: The unit is turned on but the compressor is not starting

(space heating or domestic water heating)

P

OSSIBLE CAUSES

The unit must start up out of its operation range (the water temperature is too low).

C

ORRECTIVE ACTION

In case of low water temperature, the system utilizes the backup heater to reach the minimum water temperature first (15°C).

• Check that the backup heater power supply is correct.

• Check that the backup heater thermal fuse is closed.

• Check that the backup heater thermal protector is not activated.

• Check that the backup heater contactors are not broken.

Symptom 3: Pump is making noise (cavitation)

OSSIBLE CAUSES

There is air in the system.

Water pressure at pump inlet is too low.

P C

ORRECTIVE ACTION

Purge air.

• Check on the manometer that there is sufficient water pressure. The water pressure must be >0.3 bar

(water is cold), >>0.3 bar (water is hot).

• Check that the manometer is not broken.

• Check that the expansion vessel is not broken.

• Check that the setting of the prepressure of the expansion vessel is correct (refer to

"Setting the prepressure of the expansion vessel" on page 11

).

Symptom 4: The water pressure relief valve opens

P

OSSIBLE CAUSES

The expansion vessel is broken.

The water volume in the installation is too high.

C

ORRECTIVE ACTION

Replace the expansion vessel.

Make sure that the water volume in the installation is under the maximum allowed value (refer to

"Checking the water volume and expansion vessel pre-pressure" on page 10 ).

Symptom 5: The water pressure relief valve leaks

P

OSSIBLE CAUSES

Dirt is blocking the water pressure relief valve outlet.

C

ORRECTIVE ACTION

Check for correct operation of the pressure relief valve by turning the red knob on the valve counter clockwise:

• If you do not hear a clacking sound, contact your local dealer.

• In case the water keeps running out of the unit, close both the water inlet and outlet shut-off valves first and then contact your local dealer.

Symptom 6: The user interface displays "

n

" when pressing certain buttons

P

OSSIBLE CAUSES

The current permission level is set to a level that prevents using the pressed button.

C

ORRECTIVE ACTION

Change the "user permission level"

field setting ([0-00], see "Field settings" on page 16 .

Symptom 7: Space heating capacity shortage at low outdoor temperatures

P

OSSIBLE CAUSES

Backup heater operation is not activated.

C

ORRECTIVE ACTION

Check that the "backup heater operation status" field setting [4-00] is turned on, see

"Field settings" on page 16 .

Check whether or not the thermal protector of the backup heater has been activated (refer to

Main components , "Backup heater thermal protector" on page 6

for location of the reset button).

Check whether or not the thermal fuse of the backup heater is blown

(refer to

"Main components"

,

"Backup heater thermal fuse" on page 6 for location of the reset

button).

Symptom 8: Unexpected backup heater operation

P

OSSIBLE CAUSES

Entering water temperature is too low and leaving water temperature

>25°C.

Too frequent use of the backup heater during heating operation or domestic water heating.

C

ORRECTIVE ACTION

Increase the water flow.

The water volume in the cicuit is too low.

Installation manual

24

EKHBH/XE008AA3V3

Indoor unit for air to water heat pump system

4PW48441-1B