No Radiators working after installing a Towel Rail

[nekekami]

Good Morning,

I have a Powermax 155 boiler which runs an open vented central heating system in a single floor flat. Yesterday I replaced the radiator in the main bathroom with a large towel rail. After reconnecting the plumbing to the towel rail and turning the central heating back on, none of the radiators (incl the towel rail) heat up. I have done a lot of reading and testing to try to narrow down the problem, things I've done/checked:

1) Bled every radiator in the house, all bleed clean water almost straight away with no hissing or air
2) Bled the Central Heating Pump via the central screw, no air, small amount of dirty water
3) Turned both valves on the Towel Rail off to try to isolate it, still no joy.
4) Checked the CH Pump, it seems to work fine, pipe is very hot flowing into the pump, slightly hot after the pump and increasingly cold.
5) CH Pump is VERY hot, nearly scalding to touch.
6) Initially bleeding the Towel Rail did cause a hissing and the inlet valve was super hot but it did nothing more than get luke warm
7) Removing the bleed valve from the Towel Rail and peering inside revealed that water has only filled halfway up the Tower Rail
8) After initial bleeding there is no further water leaking from the CH Pump when it is bled.

Could this be that there is a lack of pressure to run the towel rail? It is approximately 1 metre below the header tank and replaced a small double walled radiator. The CH system uses a load of manifolds in series and the pipe work running from each manifold is 10 mm.

I have turned off the CH pump over night to let it cool down but I am very confused, it sounds like there is air in the system but if there is air why does bleeding the radiators or pump not release it?

Any help or guidance would be very much appreciated.

 

[Thoggy]

You've got an issue with the pump or an air lock hard to say exactly without actually being there and checking.

 

[nekekami]

Thanks for the response Thoggy, my feeling is that it was all working fine before the radiator/towel rail swap so the pump shouldn't have failed (would be a bit of coincidence!), I am thinking down the air lock route. Anything else I could check/do?

 

[Thoggy]

Are there any air vents on the pipe work?

 

[nekekami]

None that I can see, the pipe work after the pump doesn't have any, it just runs past a load of manifolds (four connections on each). Where should these be?

 

[Thoggy]

For the sake of it mate I would just give a plumber a bell it's hard to give advice without actually being there, if you want a warm house just give someone trusted a call shouldn't take to long to have you up and running again. If you try to sort yourself you could end up making things worse and costing you in the end.

 

[MrMeek]

if its open vented, completely drain down system again, the refill might get rid of air lock if there is one, if that doesnt solve it call out a plumber theirs loads of things that could be at fault

 

[cjg]

slow fill is better than bannging in galls in at one go , takes longer of course but you tend to get less air locks (thats if it is a a/lock) sounds more like poss. pump air or low power ( pump runs but has no real flow) hope you get it sorted cjg

 

[bewsh]

Have you checked the F&E tank has water in it? If the float valve has jammed then the system won't be full of water and the pump will be running dry - hence it being scalding to touch. And if no air or water is coming out of the radiators it sounds like no water is entering the system.

Did you drain the entire system or just isolate the old radiator on the valves and just drain the radiator water?

 

[nekekami]

The F&E tank has water in it. Water does come out of all radiators (other than the towel rail).I just isolated the old radiator, however, the inlet valve wouldn't fully close so some water was drained from the system during the fitting of the towel rail.

 

[MrMeek]

is the f&e higher then the rad? it sound like it hasnt filled up :/ air lock or blockage, just completely drain down and fill back up see if it works

 

[nekekami]

The F&E is about 0.9 m above the top of the Towel Rail, I was wondering about that because the towel rail has only half filled up with water. Could it be that the towel rail is too high? I will try to drain down the system and fill it back up, if that doesn't work I will call out a plumber.Any other suggestions? Really appreciate all the replies.

 

[fast phil]

drain it down and let the f an e tank fill right up then bleed the rads starting from the furthest away make sure the f an e tank has a lot of water in while bleeding the rads if it starts to get low while bleeding stop and let it fill up if that dont work you will have to call a plumber

 

[MrMeek]

drain it down and let the f an e tank fill right up then bleed the rads starting from the furthest away make sure the f an e tank has a lot of water in while bleeding the rads if it starts to get low while bleeding stop and let it fill up if that dont work you will have to call a plumber

the hight of the tank sounds fine, i think you just have a blockage or a air lock drain down completely and turn water back on for the tank and system to fill back up, if that doesnt work honestly just get a plumber in or we will be here all day listing endless possibilities mate

 

[nickelarsed]

could be a blockage. If it is it usually happens where the cold feed meets the c/h pipe. Get a magnet and run it over the pipework, usually behind the pump where the pipes meet. If the magnet sticks hard you have a blockage and would explain why the pump is hot and you have no pressure.

 

[nekekami]

Ok, think it's time to do a drain down. It's a flat so there are no downstairs radiators, is there a specific order I should use for draining down and filling up? Also should I be adding inhibitor when refilling? Thank you so much for all your response.

 

[nekekami]

FIXED!

The plumber came round and removed an airlock in the down pipe from the header tank. Thank you SO much for all your help guys.

 

[Dannyparty92]

Air lock or blockarge? How did he fix it?

 

[GasMark1]

did you turn the pump off when you drained down ...? chances are you;ve burnt it out
Mark