The following table is to be used as a guide to possible problems. It is not exhaustive and all problems should be investigated by the installer or another competent person.

Users should not attempt to repair the system themselves.

At no time should the system be operating with the safety devices by-passed or plugged.

Fault symptom

Possible cause

Cold water at taps

Scheduled control off period

(systems with DHW tank)

All hot water from DHW tank used

Heat pump or electric heaters not working

Heating system does not get up

Prohibit, schedule or holiday mode selected

to set temperature.

Incorrectly sized radiators

The room in which the temperature sensor is located is at

a different temperature to the rest of the house.

Battery problem *wireless control only

The cooling system does not

When the water in the circulation circuit is unduly hot,

cool down to the set tempera-

Cooling mode starts with a delay for the protection of the

ture. (ONLY for ERSC(D) and

outdoor unit.

ERST20C(D) models)

When the outdoor ambient temperature is significantly low,

Cooling mode does not start running to avoid freezing of

the water pipes.

After DHW operation room tem-

At the end of the DHW mode operation the 3-way valve

perature rises a little.

diverts hot water away from the DHW tank into space

heating circuit. This is done to prevent the cylinder unit

components from overheating. The amount of hot water

directed into the space heating circuit is dependent on the

type of system and the pipe run between the plate heat

exchanger and the cylinder unit.

Heating emitter is hot in the DHW

The 3-way valve may have foreign objects in it, or hot wa-

mode. (The room temperature

ter may flow to the heating side due to malfunctions.

rises.)

Schedule function inhibits the

Freeze stat. function is active.

system from operating but the

outdoor unit operates.

Pump runs without reason for

Pump jam prevention mechanism to inhibit the build up of

short time.

scale.

Mechanical noise heard coming

Heaters switching on/off

from cylinder unit

3-way valve changing position between DHW and heating

mode.

Noisy pipework

Air trapped in the system

Loose pipework

Water discharges from one of the

The system has overheated or overpressurised

relief valves

Small amounts of water drip from

Dirt may be preventing a tight seal in the valve

one of the relief valves.

An error code appears in the

The indoor or outdoor unit is reporting an abnormal condi-

main remote controller display.

tion

All setting will be saved for 1 week with no power, after 1 week Date/Time ONLY will be saved.

Maintenance

Maintenance to the cylinder unit and hydrobox should be carried out annually by a competent person only. Users should not try to service or replace parts of the cylinder unit

or hydrobox themselves. Failure to observe this instruction could result in injury to the user, damage to the unit and the product warranty becoming invalid.

In addition to annual servicing it is necessary to replace or inspect some parts after a certain period of system operation. Please see tables below for detailed instructions.

Replacement and inspection of parts should always be done by a competent person with relevant training and qualifications.

Parts which require regular replacement

Parts

replace every

Pressure relief valve (PRV)

Air vent (Auto/Manual)

Drain cock (Primary/Sanitary circuit)

6 years

Manometer

Inlet control group (ICG)*

OPTIONAL PARTS for UK

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