Boiler problem

[winniwingate13]

Hi I have this problem with my heating system. I'm getting air blowback into the header tank which knocks off the boiler, ie flashing red light.

Any suggestions would be appreciated.

 

[D_Hailsham]

Need a lot more info!

Make and model of boiler would be a start.

Read http://www.diynot.com/forums/viewtopic.php?t=6026

 

[winniwingate13]

Hi The boiler is a pottington supreme. The gurgling noise coming from the header tank overflowed last night out of the overflow pipe. Hope this helps. Brian.

 

[D_Hailsham]

Hi The boiler is a potterton supreme. The gurgling noise coming from the header tank overflowed last night out of the overflow pipe. Hope this helps. Brian.

I presume you mean the small tank which feeds the CH system not the large cold water tank. Something is causing the water level to rise too much (it will rise a bit due to expansion).

If so, it could be a blocked feed from the tank to the CH system. Tie up the ball valve then let some water out of the CH system via a drain valve. If the water level in the header tank does not go down, then there is a blockage in the feed pipe.

Also check the water level in the tank when cold. It should be about an inch or two above the lower outlet. The ball valve must be adjusted so the valve opens when the level is above the outlet.

 

[winniwingate13]

Thanks for the reply. I have checked the small tank and it seems ok. The reason for the overflow was what sounded like air being pushed into the small tank from the boiler, that is when the boiler switches off. It seems to happen about every 4 to 8 weeks.

 

[D_Hailsham]

Thanks for the reply. I have checked the small tank and it seems ok. The reason for the overflow was what sounded like air being pushed into the small tank from the boiler, that is when the boiler switches off. It seems to happen about every 4 to 8 weeks.

Air in the system should not cause the water level to rise. Have you watched the water level to see what happens or are you just relying on your ears? Under normal conditions the water level will be just above the outlet when cold and rise, but not as far as the overflow, when hot. If water is rising beyond the overflow then either the level is too high when cold or water is coming up the vent pipe - or the ball valve is leaking.

The fact that it only occurs every 4-8 weeks suggest that the level is rising quite slowly.

 

[winniwingate13]

ok thanks, but what do you think is causing all the noise and vibrating coming from the small tank plus boiler shut down

 

[tonybhoy]

Possibly your pump is faulty or a motorised valve . Flashing red light means (I think) an external (component) fault .

 

[winniwingate13]

I changed the 3 way valve about 3 months ago because the rads were getting hot when just the hot water was on.

 

[swbjackson]

That's normally cause by muck in the seating of the valve. It's possibly an indication that your system is sludged up. Partial blockages in the pipework can cause all sorts of problems. I'd look at flushing the system.