Performing maintenance
90 Instruction manual GWV
15
s
6. Switch the electronic controller ON by setting the On/Off switch to position I.
The display will now show
INTERNAL CHECK
for about 10 seconds and
go to the main menu.
7. Activate the 'ON mode' by going through the following steps:
- Press the blue arrow once ( ) to position the cursor in front of
ON
and
press .
- Confirm the
START OPERATION
by pressing .
8. If there is no heat demand, increase Tset (11.4 "Setting the water
temperature"). Note the original setting. If there is no demand, draw some
hot water off to create demand.
9. Check whether the heating cycle runs correctly (2.3 "The appliance's
heating cycle").
10. If you have adjusted T
set
, return it to the original value (11.4 "Setting the
water temperature").
11. Carefully remove the sheeting from the front of the appliance.
12. Check the supply and burner pressures (3.11 "Checking the supply
pressure and burner pressure") and adjust these where necessary.
13. Check that all components of the flue gas system are properly attached.
14. Check the pressure differential across the orifice plate of the pressure switch
(see the table). If the pressure difference is too low, the flue gas outlet and
air supply should be checked for blockages.
Pressure switch differential
15. Test the operation of the overflow valve of the protected cold supply set-up.
The water should spurt out.
16. Test the overflow operation of the P-valve. The water should spurt out.
17. Check the drainage pipes from the discharge points of all valves and remove
any scale deposits that may be present.
18. Drain (6 "Draining") the appliance.
INTERNAL CHECK
MENU
»OFF
^ ON
È WEEK PROGRAM
Appliance Observed pressure differential across the pressure switch
(Pa)
GWV 120 > 66
GWV 150 >
75
GWV 200 >
92
