Glow-worm Xtramax - Manual (Page 17)

17
4000116705-2
Flow
control valve Drain point
Filling
device
Bypass
valve
Domestic
water
Heating
circuit
Return
Additional
expansion
vessel
(if required)
Boiler
Pressure
reducing valve
and Check valve.
Max. supply pressure
16 bar.
(supplied)
Thermostatic
mixing valve
(supplied)
Thermostatically
controlled
hot water
Boiler
"set temperature"
hot water
Temperature
adjustment
(supplied)
Hot
Cold supply
MIX
H C
9 Piping System Installation
There are 2 options for the domestic hot water supply :
1 - Piping the hot water supply without the use of the mixing
valve to provide hot water to all taps at the same temperature.
2 - Piping the hot water supply using the mixing valve (supplied)
to provide hot water at boiler hot water “set temperature” to one
tap and thermostatically controlled hot water to another tap(s).
To pipe the hot water supply using the mixing valve, refer to
diagram 9.2. This shows one outlet supplying hot water at the
boiler hot water "set temperature" and one hot water outlet at
a temperature pre-set at the mixing valve. The mixing valve can
be set between 35 and 60°C. It is recommended that the valve
is adjusted (and locked) by the installer to the desired
temperature.
Note: The thermostatic mixing valve has 22 mm connections,
22x15 mm reducers will need to be fitted.
The connections to the mixing valve are :
H - Hot water supply from boiler
C - Reduced cold water supply
MIX - Thermostatically controlled outlet
Warning : It is strongly recommended that the cold water
supply to the mixing valve is taken from the reduced side of the
pressure reducing valve (supplied)
Note 1 : The mixing valve is fitted with two in-line strainers, one
on the hot inlet and one on the cold inlet. For servicing details
of these, refer to the separate instructions supplied with the
mixing valve.
Note 2 : The mixing valve incorporates a "rapid fail-safe" device
which will automatically close the valve to safety in the event of
supply failure on either hot or cold water.
9.7 Gas connection
Gas Safety (Installation and use) Regulations
In your interests and that of gas safety, it is the law that ALL gas
appliances are installed and serviced by a qualified registered
person in accordance with the above regulations.
9130
Diagram 9.2
20 mm
min.
600
120
169
Ø 105 or 125 core drill
= =
900
20
65 234
9090
• The supply from the governed gas meter must be of adequate
size to provide a constant inlet working pressure of 20 mbar (8
in w.g.).
To avoid low gas pressure problems, it is recommended that the
gas supply is connected using 22 mm pipe.
• On completion, the gas installation must be tested using the
pressure drop method and purged in accordance with the
current issue of BS6891.
Diagram 9.1