Radiator Not Working

Ballyman

Hi



The radiator in my dining room doesn't heat up like the rest in the house. It's only lukewarm while the others are piping hot.



I bled the rad but there was no air in it as water came out the second I opened the nut. I have checked the temp of the inlet and outlet pipes to the rad and these are only lukewarm also compared to all the others. It only seems to be a recent problem (last few weeks) as I would have noticed if it wasn't working properly before that.



I have a total of 8 rads. 4 upstairs and 4 downstairs.



Anyone have any idea what the problem might be??

delly

Sounds strange alright. Well the bleeding is the first option but as you've already tried that then it has to be something else. Other factors could be the pressure in your system could be low or the pump speed too slow, but as only one rad is affected I would doubt it.

My final guess would be the thermostatic inlet or lockshield outlet being some way blocked or restricted. I know that the thermostat knob especially can become locked in the closed position. I'll do a quick search to see if I can find a thread with the unlocking fix.

johnny_adidas

sounds like a stuck valve to me. can happen with the thermostatic ones. also happened to one of my manual towel rad valves before. stripped down the valve and made sure it was working correctly. working perfectly ever since

delly

Ok in response to another similar problem I found this:

Probably the thermostatic valve is stuck closed, remove the head and push the pin in and out a few times to release it. If no improvement then it may be sludge, but doubtful since other rads are working ok.

Do you actually have thermostatic valves on the rads?

Ballyman

I don't, or at least not as far as I am aware. Whereabouts are they and what do they look like??

delly

Something similar to this on your radiator:

Ballyman

I don't have one of those!!

I don't think it's the actual radiator where there might be ablockage as the pipes coming into the rad is only lukewarm as well so it seems to me that the problem is actually further back.

Is there any way I can verify this, without digging up the floor of course !!!

delly

Well the problem could still be in the rad itself as the water could be taking so long to pass through the rad that it is already lukewarm by the time it enters. Its the same as if you close off the return valve on a rad but the input is open, it still has an unobstructed route from the boiler, but because the end is blocked off the water has nowhere to go and will therefore remain cold.

The sludge buildup could be another reason, how old is the house?

JamesM

delly wrote:

Well the problem could still be in the rad itself as the water could be taking so long to pass through the rad that it is already lukewarm by the time it enters. Its the same as if you close off the return valve on a rad but the input is open, it still has an unobstructed route from the boiler, but because the end is blocked off the water has nowhere to go and will therefore remain cold.

The sludge buildup could be another reason, how old is the house?

Delly is asking the right questions. If the house is old, it could be sludge.
Maybe try turning off all the other rads and see if the water pushes through to that rad. If so, balancing might work.
Jim.

Ballyman

The house is around 10 years old. I checked the inlet again last night and the temperature seemed much much hotter but the rad was still only lukewarm???

The nut at the other side of the rad to the inlet valve is open also. I adjusted this ut it made no difference so I put it back to the fully open posiion.

I'll try turning off the downstairs rads this evening and see if that makes any difference.

Elfish

I'd be thinking to balance the system. You have to adjust nuts of some of the other radiators in the house, not just the one that isn't heating.

Also if you have opened the system, put in some anti corrosion liquid while you are at it (not sure exact name of it but any plumbers shop or hardware would have tins of it).

A proper plumber (which i amn't) would probably fix this dead quick from his own rules of thumbs for where best to balance, where locks occur etc.

tapest

Hi
Depending on the actual pipe run...you may have an airlock further back on system ...Pipe can run flat, then drop doen , then tise up again.-no problem. Reverse is nit great...run flat ,rise up, then drop again can leave air in top of pipe loop,,,and should have an auto bleed valve fitted on top of pipe loop....If you know what I mean.
JamesM will explain it better
t

Ballyman

I'm going to try balancing the rads first. I got a link over on askaboutmoney.com on how to do it so i'll give that a go first.

I presume a plumber would either not bother to come out to me as it's too small a job or else come out and charge me €4K for adjusting a knob somewhere??

delly

Ballyman wrote:

I got a link over on askaboutmoney.com on how to do it

You mean.....you visit other forums? I feel so used