lighting problems

[azznwab]

had a fault with heat exchanger so changed that, then preasure kept goin up while ch was on, so iv pumped it up the expansion vesel up 2 0.7 of a bar. (followed correct steps with link i as forwarded). now my boiler wont light. wen it does it goes out in bout 5 seconds. then wont light 4 a while after. iv tryed holding that red button. (iv got instructions on bk of a panel 4 that)

boiler is worcester 28cdi

 

[nickso]

which lights show up after it fails to fire? the light combination will give a massive clue to what is happening.

 

[azznwab]

iv got 4:- power, ch, tap w, pilot or wot ever it is.

obvouisly my powers on, and the ch n tapw come on wen there in demand, n the piolet comes on briefly n goes out wen the flame does in couple of secs

 

[nickso]

ok, but when it fails to light there is generally one or more lights flashing, this tells you what sort of area you are looking at for failure.

 

[azznwab]

they dont flash wen i just turn it on. but if i try pressin the red lighting button just 4 1 sec then the ch flashes but if i hold the red button in again for 2 secs then the flashing stops n sum times the boiler will lite, n then like i sed it just goes out with the piolet lite with no other change to the other lights. eg flashing

 

[azznwab]

just turned it on again n it lasts for 10 secs b4 goin out. wot sounds like the pump still runs tho

 

[nickso]

are you sure there is water in it and no airlocks? is the pump noisy?

 

[azznwab]

not banging or grinding or anything. but it sounds like it is a bit noisier than useuall

 

[gblades]

I am no expert but from watching the engineer replace a part on my worcester boiler earlier today I would make sure you bleed the pump.

If the pump has an airlock it wont pump water and the heat exchange will overheat and trip the button. Thats what mine was doing while the enginner bled the air out of the pump and once that was done it was fine.

 

[nickso]

our novice friend could be on to something.

 

[azznwab]

how did he bleed it

 

[gblades]

There is a large silver screw in the middle of the pump. Turn anticlockwise to open and bleed.

 

[Gasguru]

I find the CDi's are a pig to get the air out. Check the cap on the auto air vent is loose by a few turns, also check it isn't leaking water.

Turn the gas OFF. Then run the boiler in heating mode and cycle the hot tap on/off a few seconds at a time to expel all the air into the rads and through the auto air vent. Only when the pump is running nice and quiet turn the gas back on and fire it up. You will have to press the reset from time to time as it locks out with failed ignition.

 

[azznwab]

shall i turn gas off out side? cant c anything accessable on boiler.
tryed it b4 got this msg with gas turned on to boiler but think its safe
due to safty cut out. plus water dripped on my switch panel

nice1 just got pop out 4 hour do it wen get bk. any other tips i mite need plz drop them in.

cheers