Boiler opperation intermittent

Hi,

I have been trying to solve this problem for a week now and the house is not 7 deg C.

I have a Glow Worm back boiler - approx 10-15 years old, not sure of model because I'm at work.

The problem is that the boiler stay on for approx 3 mins before the thermostat on the boiler cuts it out. This happens whilst the heating is on and/or just hot water.

I replaced the Y valve (due to some poor advice) and have now traced the electrics to the boiler. It seems that the water is getting too hot at the boiler end.

I know the pump is working because it distributes heat quite well. But i don't know if it is working well enough.

Reading through some of the other posts it might well be because of a build up of muck in the boiler, but any advice on what to do next would be appreciated....

Thanks!

chunky_chap said:

I know the pump is working because it distributes heat quite well. But i don't know if it is working well enough.

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I dont understand that it distibutes heat quite well as your hot water and rads are cold!

Even if the pump feels as though its working, it may not be.

Is header tank full of water, and if so, pump is indeed working correctly, suspect a blockage in cold feed pipe from the header tank where it enters the system.

David

Hi thanks for the reply.

The pump seems to work ok when the boiler is running... i.e. it heats the top of the house.

The header tank is full. How would I test if there is a blockage from the header tank?

Thanks

drain some water out of the system and see if the level drops

The pump seems to work ok when the boiler is running... i.e. it heats the top of the house.

Click to expand...

it will do that by convection

Excellent, will try that later!

Ok, so the water level in the header tank falls as water is let out of the system, and tops itself back up.


Is it likely that there is a blockage near the boiler? As the pipes from the boiler get very hot very quickly and a boiling sound happen before the boiler switches itself off.

Is there a way of testing that the pump is working effectively?.... I know that its at least on as I have hear its hum.

Thanks in advance!

I have a Protherm 80E boiler. When running hot water, the boiler tends to cut out when the temprature reaches 50 degrees despite the thermo being set at 60. The boiler then fires up agaqin when the thermo reads about 40 degrees and so on. Can anyone help please?