Central Heating- Radiators going cold one by one

[lesleyrlynch]

Please please can anyone help......we moved into this house 18 months ago and a couple of weeks ago the front room radiator went cold, a couple of days later followed by the landing. Now two of the bedrooms are only luke warm. The boiler is still firing up, we have hot water and one radiator working ok.

Trying to find the problem has been a nightmare .....One person said, you need a new boiler, the next engineer that came said we need to find the pump (which we can't) then we were told it was a gravity fed system. We have had every carpet up upstairs to try and find this elusive pump. If it helps we have a tank in the loft and then one which is lagged in the airing cupboard. We reckon this system has been here since the house was built over 30 years ago.

We just want someone to help tell us what the problem is as we have had 3 different answers

 

[seco services]

i take it you have a back boiler

 

[twgas]

have you looked behind boiler?

 

[lesleyrlynch]

No we don't have a back boiler

 

[lesleyrlynch]

Sorry for sounding thick but do you mean behind the boiler in the kitchen? This is just against the kitchen wall

 

[twgas]

what about inside boiler case

 

[lesleyrlynch]

Just had a look in the boiler case and can't see anything. If it helps the boiler is a Glo Worm Space Saver 50

 

[JohnD]

if it is 30 years old and has not been looked after it is probably full of sludge. It is possible to clean this out but I would have expected a heating engineer to diagnose it.

When you bleed the radiators, what colour is the water that comes out?

If you bleed the highest radiator in the house, does water squirt out vigorously? Do you know where the drain cock is?

When you look in the small feed and expansion tank in the loft, how deep is the water? Is there mud in the bottom? Does it have a tight-fitting cover?

Gravity feed systems are quite rare this century. if there is no sign of a pump near the boiler or in the airing cupboard, maybe you haven't got one. though I would have expected a boiler engineer (but maybe not every plumber) to be able to tell if there was one by looking at wiring round the boiler and any room thermostat.

A pump

about six inches across, with a large pipe going in from each side, and with an electrical flex goung into it.

As it is over 30 years old I imagine most people will be telling you you need a new one. They may well be right but giving it a clean is likely to help and not likely to do any harm. You can do this yourself for about £50 in parts and chemicals if you like DIY.

 

[lesleyrlynch]

when we bleed the radiators the water is clear - unfortunately we are not sure where the drain cock is, but the water does come out vigorously. It could be that we need a new one but we were going to give it one last chance!

 

[JohnD]

you will need to find the drain cock if you are going to clean it.

Or fit a new one. You can get a radiator valve with drain built in, which is handy.

You are looking for:

preferably near the lowest point on the system but might be by the boiler

I have a feeling that you are going to have to get a pump and room stat fitted. I can't see how you could get good performance on gravity in an ordinary house. I may be wrong, I am just a householder.

 

[twgas]

follow the smaller lower pipe from boiler and you should find a pump, eventually!!!

 

[lesleyrlynch]

thanks we have found the drain cock now and it is at the bottom of the boiler it is like your picture shows (bottom pic) - we have a room stat in the lounge , but it is not very effective as it only clicks on at about 20 degrees and the highest it goes is 25!

 

[JohnD]

there will be a wire from this stat.

The wire will probably go to the boiler, or near it. there will probably be several other wires here collected together. If you have a pump, it will be switched on by the stat, so there will be a wire to the pump from the wiring centre.

 

[lesleyrlynch]

Thanks., going to bed now will check out tomorrow

 

[superdupergasman]

What about underneith the downstairs floor.