Estia HWS-1501CSHM3-UK, Инструкция по установке и обслуживанию

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FIG. 7 Thermal cut-out
6.0 MAINTENANCE
6.1 MAINTENANCE REQUIREMENTS
Unvented hot water systems have a continuing main-
tenance requirement in order to ensure safe working
and optimum performance. It is essential that the
Relief Valve(s) are periodically inspected and manu-
ally opened to ensure no blockage has occurred in
the valves or discharge pipework. Similarly cleaning
of the strainer element and replacement of the air in
the Expansion Vessel will help to prevent possible
operational faults.
The maintenance checks described below should be
performed by a competent installer on a regular basis,
e.g. annually to coincide with the air to water heat
pump maintenance.
6.2 SAFETY VALVE OPERATION
Manually operate the Temperature/Pressure Relief
Valve for a few seconds. Check water is discharged
and that it flows freely through the tundish and
discharge pipework. Check valve reseats correctly
when released. NOTE: Water discharged may be
very hot!
Repeat the above procedure for the Expansion Valve.
6.3 STRAINER
Turn off the cold water supply, air to water heat pump
system and cylinder heater. The lowest hot water tap
should then be opened to de-pressurise the system.
Remove the Pressure Reducing Valve Cartridge by
unscrewing from the housing. Pull the Reducing
Valve cartridge from the housing to access the strainer
mesh. Wash any particulate matter from the strainer
under clean water. Re-assemble ensuring the seal is
correctly fitted, DO NOT use any other type of seal -
ant. Ensure the Pressure Reducing Valve Cartridge is
fully tightened.
6.4 DESCALING CYLINDER HEATER
Before removing the cylinder heater the unit must be
drained. Ensure the water and electrical supply and
air to water heat pump are OFF before draining .
Attach a hose pipe to the drain cock having sufficient
length to take water to a suitable discharge point below
the level of the unit. Open a hot tap close to the unit
and open drain cock to drain unit.
ISOLATE FROM MAINS BEFORE REMOVING
TERMINAL COVER.
Open the terminal cover. Disconnect the link wires
connecting the thermal cut-out to the cylinder heater.
Carefully remove the thermal sensor from its pocket
on the cylinder heater by pulling outwards. Care-
fully remove the thermal cut-out sensing bulb from
its pocket by pulling outwards. Remove the element
tail insulating shroud by pulling it outwards from the
element.
Unscrew the cylinder heater backnut. A key spanner
is provided with the unit for easy removal/tightening
of the 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 and gently lever up and down. 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. Ensure sealing surfaces are
clean and seals are undamaged. If in doubt fit a new
gasket.
Replace the cylinder heater ensuring the element tails
are in the vertical plane (see Fig. 6). Secure in place
by re-fitting cylinder heater backnut and tightening.
Replace the element tail insulating shroud by carefully
pushing it over the element tails until it sits flush with
the face of the element mounting plate. Replace the
thermal cut-out into 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 ele-
ment tails. Replace the thermal sensor in the left hand
pocket of the cylinder heater. Ensure it is fully inserted
behind the thermal cut-out, and the securing grommet
is pushed into the open end of the pocket.
MAINS TERMINAL
BLOCK
SENSOR TERMINAL
BLOCK
THERMAL CUT-
OUT
TERMINAL BRACKET
NOTE:
THE COVER AND ELEMENT ASSEMBLY HAVE BEEN REMOVED
FROM THIS VIEW FOR CLARITY
RESET BUTTON LOCATED
ON THIS FACE