HAMWORTHY HEATING LTD
17
WEYMOUTH
500001112/C
10.7 Non-Return Valve On Standard Unit
(part n° 531911039)
1) Follow the procedure for removal of the pump (see section 10.2). The non-return valve is inside the brass
fitting shown in figure 29.
2) Unscrew the brass fitting from the silver nut it is screwed into.
3) Push the valve out from the brass fitting as shown in figure 30.
Figure
29
Figure
30
10.8 Non-Return Valve On Advanced Unit
(part n° 531911040)
Figure 31
1) Follow the procedure for removal of the pump (see section 10.3).
The valve is inside the brass quick release fitting shown in figure 31.
2) Unscrew the brass fitting from pump.
3) Push the valve out from the brass fitting (see fig 30).
10.9 System Expansion Vessel Diaphragm
(Part n° dependant on model and serial n°. Consult Hamworthy Heating for details)
1)
Turn off the boiler and electrically isolate the unit.
2) Close the system isolating valve and isolate the mains water supply to the header tank.
3)
Drain the pressurisation unit and expansion vessel.
Note!
Leave the drain cock open. Disconnect the
expansion vessel pipe-work.
4) Unscrew the diaphragm top connection (normally a brass nut at the opposite end to the water entry).
5) Remove the bolts from the flange at the base of the vessel and remove the diaphragm.
6) To replace the diaphragm top connection (normally a brass nut at the opposite end to the water entry).
7) Screw the plug lightly into the diaphragm top connection and pull it up through the expansion vessel.
8)
Lockup the diaphragm top connection and tighten the water connection flange screws. Note! Ensure that
the diaphragm is not twisted.
9) Reconnect the expansion vessel pipe-work.
10) To restart the system follow the steps in section 7.
