DORCHESTER DR-SE 18, Инструкции по установке, пусконаладке и обслуживанию

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HAMWORTHY HEATING LTD
Page
DORCHESTER DR-SE 500001062/D
9
13.4 Inspection of the Waterside Surfaces and Mag-
nesium Anode.
Note: On no account remove the magnesium anode
without checking to ensure that the heater is fully
isolated and pressure removed.
Isolate the cold feed, hot flow and circulation con-
nections and 3 way vent valve if fitted. Connect a
hose to the drain valve at the bottom left hand side
of the heater. Run the hose to a convenient drain
and open drain valve.
Ensure heater is fully drained.
The heater is fitted with a single magnesium anode
which hangs vertically within the vessel and is lo-
cated in front of the draught diverter. Release and
unscrew the top M8 nut and remove the green/
yellow earth bonding connection between the anode
and the tank. Release and unscrew the 1 in BSP
cap nut which secures the anode (35 mm across
flats) and withdraw. Examine the anode for corro-
sion and replace if the diameter has been reduced
to less than 18 mm. When replacing the anode use
an approved sealant for potable water systems and
ensure the earth bonding connection is remade on
top of the anode to ensure good electrical contact to
the tank. Also check cleanliness of bonding connec-
tion at the tank.
Note: Where access above the heater is limited, it
may be possible to replace the solid anode with a
more flexible segmented anode.
Remove the four self-tapping screws from the circu-
lar casing inspection port located to the right of the
gas control valve.
Remove the panel and the disc of insulation be-
neath to expose the inspection port cover. Release
and remove the eight M10 bolts and take off the
inspection cover complete with its sealing gasket.
Inspect the interior surfaces of the heater for depos-
its. If deposits are apparent, they can be flushed
through the drain by a water jet applied through the
inspection port, or the vessel can be chemically
cleaned and flushed. After cleaning, replace the in-
spection cover with new sealing gasket.
Note: On no account should a metal scraper be
used to remove deposits since this may result in
damage to the glass lining.
13.5 Assembly Following Servicing
Close drain valve and remove hose.
Open the isolation valves on the heater cold feed,
hot flow, circulation and common vent connections.
Allow the system to fill with water.
Check to ensure that there are no leaks from the
anode connection and the drain valve. Check for
leaks at the inspection port and then replace the
insulation disc and the exterior casing panel with the
four self-tapping screws.
Slide the gas burner assembly into position beneath
the heater and refit in the reverse order to that de-
tailed in Section 13.1.
Relight burner in accordance with Section 12.3 and
check operation of controls.
Note: The maintenance of the water side of the sys-
tem may require additional cleaning and disinfecting
before being placed into service Refer to BS 6700.
14.0 RECOMMENDED SPARES
Description
Part No.
Gas Control Valve (710 Minisit)
533903039
Overheat Safety Device
(Limit
Stat) 747433982
Thermocouple 747439880
Pilot Burner (Natural Gas) 361150066
Pilot Injector (Natural Gas) 331101686
Spark Electrode c/w Lead 333805318
Main Injector 3.5mm
(DR-SE 18 - Nat. Gas)
330513691
Main Injector 3.8mm
(DR-SE - Nat. Gas)
532902033
Inspection Port Gasket 339008966
Magnesium Anode
(DR-SE
18) 363202253
Magnesium Anode
(DR-SE
20) 363202246
15.0 OPTIONS
15.1 Time Clock Control
15.1.1 General
A solenoid valve kit can be supplied either factory
fitted to the heater or for site fitting which enables
the heater to be controlled by an external source.
HHL Part No. 563605008
15.1.2 Assembly
Ensure the gas supply to the heater (if connected) is
turned off.
Remove burner assembly as detailed in Section
13.1.
Disconnect thermocouple, pilot bundy tube and
Piezo lead from gas control valve.
Unscrew compression fitting at gas valve outlet and
remove valve.
Unscrew burner injector and lock nut, remove gas
supply pipe and discard.
Assemble the two sections of pipework supplied into
the solenoid valve: straight pipe in valve outlet,
curved section in valve inlet using suitable gas pipe