Glow Worm Compact 100 E - water not heating up

28 Oct 2012
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United Kingdom
I have a glow worm compact 100E that shows the gas pressure exactly 2.

Sequence of events:
1) I switch on taps for hot water.
2) The "SANITARY DEMAND" light takes 10 seconds to glow.
3) Once it starts glowing then "BURNER IGNITION" light takes 5 seconds to glow.
4) "BURNER runs for 5 seconds then the red light "BOILER LOCKOUT" gets glowed.
5) I press the "RESET BUTTON" then the red light is off.
6) During all the above "SANITARY DEMAND" light is fluctuating with a sequence of clicking sounds OR
7) During all the above "BURNER IGNITION" light is fluctuating with a sequence of clicking sounds

8) If I am lucky then after leaving the hot water tap ON for 5 min and trying all the above, the hot start flowing OK for good time any further trouble

all the had to done every time, I switch on hot water tap.

Please note that when I leave the boiler on "WINTER SETTINGS" i.e. both water and radiator ON then all is OK.

Please help.
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I'd hazard a guess at either a diverter or diaphragm fault, or maybe a combination of the two. Time to call a boiler engineer out to it

Incidentally your gas pressure is not 2 (if it was you'd have a major problem) the pressure shown on the front is the pressure of the water in your heating system
How do I ensure that I am approaching a competent engineer?

I stay in south Belfast
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talk to friends and neighbours horse,see if they have a contact they know and trust
after that its pot luck in the papers or ads, even then you could get lucky

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