Estia HWS-1501CSHM3-E Manuel D'installation page 7

AIR TO WATER HEAT PUMP SYSTEM
6.0
EN
8
5.8 Manually test the operation of the Pressure Relief Valve. Ensure water flows
freely from the valve and through the discharge pipe.
5.9 Fill the primary circuit following the "Water Pipe" section in the Hydro Unit
Installation Manual. Vent any trapped air by opening the air bleed point or
automatic air vent.
5.10 Switch on the electrical supply to the Air to Water Heat Pump and ensure the
programmer is set to HOT WATER mode. Check that any motorised valves or
primary pumps are working and allow the unit to heat. The hot water temperature
may be varied using the Hydro Unit remote controller, for details refer to the Air to
Water Heat Pump Owners Manual.
MAINTENANCE –
DESCALING CYLINDER HEATER
6.1 Little maintenance is required, however in hard water areas the unit will require
periodic descaling to ensure efficient operation. To descale the unit:
6.2 Switch off and disconnect the electrical supply and shut down the heat pump.
Turn off the water supply to the unit.
6.3 Open a hot tap served by the unit to relieve any system pressure. Empty the unit
by opening the drain valve in the inlet pipework.
6.4 Open the terminal cover. Carefully remove the thermal sensor from its pocket on
the cylinder heater by pulling outwards.
6.5 Disconnect the link wires connecting the thermal cut-out to the cylinder heater.
Carefully remove the thermal cut-out sensing bulb from its pocket on the cylinder
heater by pulling outwards. Be careful not to kink the capillary tube.
6.6 Remove the element tail insulating shroud by pulling it outwards from the element.
6.7 Unscrew cylinder heater backnut. A key spanner is provided with the unit for
easy removal/tightening of the cylinder heater backnut. Remove the cylinder
heater from the unit. NOTE over time the cylinder heater gasket may become
stuck to the mating surface, to break the seal insert a round bladed screwdriver
into one of the pockets on the cylinder heater and gently lever up and down.
6.8 Carefully remove any scale from the surface of the element. DO NOT use a
sharp implement as damage to the element surface could be caused.
6.9 Ensure sealing surfaces are clean and seals are undamaged. If in doubt fit a
new gasket.
6.10 Replace cylinder heater ensuring the element tails are in the VERTICAL plane (see
Diagram 3). Secure in place by re-fitting cylinder heater backnut and tightening.
It may be helpful to support the cylinder heater using a round bladed screwdriver
inserted into one of the element pockets whilst the backnut is being tightened.
6.11 Replace the element tail insulating shroud by carefully pushing over the element
tails until it sits flush with the face of the element mounting plate.
6.12 Replace the thermal cut-out capillary in the LEFT HAND pocket of the cylinder
heater. Ensure it is fully inserted and that the capillary tube is not kinked.
Ensure the capillary tube is routed such that it does not come into contact with
the element tails.
INSTALLATION AND SERVICE MANUAL