Radiators / Heating

Ben77 · 08-05-2006 1:50pm #1

Hi,
Looking to see if anyone could help answer a problem that I am having with my heating – i.e. my radiator downstairs in the kitchen is not working. All the rest are fine.

I bled every radiator in the house, which did not help. Upon bleeding the faulty one I can feel the heat starting to come into the rad (not the thermostat side) but only a slight bit. I took off the rad to have a look but did not see anything. My thoughts then were that the thermostat was faulty and I needed to bleed the system but after finding no expansion tank I realized I had a pressurized system.

I see that the gauge on my boiler is at zero and moves after a while to .2. I believe this should be at 1 approx. This obviously is a problem but if it is the root problem I am not sure. From reading around I may need to top up the system with more water?

Being a stubborn man I would love to be able to fix the problem myself before calling in the experts, so any advice is appreciated.

Thanks.

Viking House · 08-05-2006 2:10pm

The pressuse is one problem, the other problem is the water taking a preferential route.

Your system needs balencing.

Turn off your system for an hour or two to cool down, open every radiator fully, turn back on the system, check which radiator comes on first, second, third, etc. The first one you close the valve the most, the second you close a bit less and so on.

I normally close a valve fully and count how many turns it takes to fully open it , I divide the twists with the amount of rads in the house and balence accordingly.

Ok! lets say it takes 10 twists to close a fully open valve and there are 5 rads in the house, I close the first rad that gets hot 8 twists, the second rad 6 twists and so on.

To get your rad working try closing all the other rads, repressure the system and see if that works, if not you may have sludge in the system.

If that doesn't work get back to me.

Ben77 · 08-05-2006 3:54pm

Thanks very much for your response.

Before, I try this I just have one question.
I previously tried closing all theromstats ( sorry I presume this is what you mean when you say valves? ) apart from the one on the rad that is not working to try force heating this rad but that did not work.

So, my question is I should still try your description of balancing each rad?
Thanks again

crosstownk · 08-05-2006 4:15pm

Ben77 wrote:

Hi,
Looking to see if anyone could help answer a problem that I am having with my heating – i.e. my radiator downstairs in the kitchen is not working. All the rest are fine.

I see that the gauge on my boiler is at zero and moves after a while to .2. I believe this should be at 1 approx. This obviously is a problem but if it is the root problem I am not sure. From reading around I may need to top up the system with more water?

Did the rad just simply stop heating? If it was working fine before and then out of the blue just stopped then I doubt it's balancing unless someone has been fiddling with the valves. The balance valves that Viking House refers to are the ones on the opposite side to the thermostatic valves (you may have to remove a blanking cap to gain access). It's also quite possible that the system was never correctly balanced. To be sure follow Vikings instructions.

In relation to the pressure problem you should have 1 bar of pressure. You will need to locate the filling loop for this and top it up accordingly (usually this in the attic close to the pressure vessel). If the pressure continues to drop then you most likely have a leak. It is normal for the presuure to drop when you bleed any part of the system. As a result you can only bleed so much before you loose all pressure. It is possible that you may still have an airlock but if your pressure is only 0.2bar it may not be enough to force the airlock to the bleed valve. You may need to repressurise (refill) the system back to 1 bar before you can bleed the system any further.

Did you top up the system after refitting the radiator?

Ben77 · 08-05-2006 4:29pm

Yes the rad suddenly stopped working. All rads were fine before.
I bought the house new - its 5 years old.
I never touched the valves in the past just the individual thermostats.
So, would you still recommend I try balance the rads?

It is probably worth mentioning that when I tired to bleed the faulty rad I could feel the heat coming into the rad a bit. I let some water come out. However, as soon as I stopped bleeding the rad it went cold. The opposite site, the thermostat side, neither the pipe leading into the rad or the rad itself became warm at any time.

Yes the pressure I presume is a problem if it is at zero and maybe if this was corrected it may fix the problem. Sorry, I have no idea where the filling loop is?

Thanks for responding.

Ben77 · 08-05-2006 8:41pm

I did not see this response before - unsure if you updated it.
>> You will need to locate the filling loop for this and top it up accordingly (usually this in the attic close to the pressure vessel).

I am unsure what you mean by pressure vessel?
I see a pipe coming out of the bottom of the tank, which has a red draincock( I hope that is the correct word ). Is this what you mean?
Over the hot water tank in the press I see a flexible pipe that connects onto two copper pipes. This has a control on it that you can turn clockwise. Again I am unsure if this has anything to do with what you mean.

>> Did you top up the system after refitting the radiator?
No I did not, which I presume now I should have.

Ben77 · 08-05-2006 8:52pm

One thing I forgot to mention is that when the heating is off the gauge is at 0.2 - However, when I turn it on it goes back to zero. Unsure if this has any significance but thought I would mention it.

crosstownk · 09-05-2006 12:03am

It sounds to me like you may have a leak - but to determine this you really need to locate the pressure vessel. In some newer houses it is located above the boiler. It is a cylindrical in shape approx 12" in diameter or less. Crimson/red seems to be a popular colour for them. It maintains the pressure in the system and allows for expansion using a diaphragm set up.

Every time you bleed you release pressure from the system and this can only be corrected by filling with water. Basically your water feed to the house connects via a tap to your heating system. You should follow the mains water feed in your house and see what it feeds. Usually the feed goes to a)your kitchen sink, b) your attic tank and c)your heating. Everything else is fed by the tank in the attic. When you open the correct valve the pressure guage for the heating will rise - use the trial and error method - ie turn all valves one at a time until the pressure rises. If nothing happens return the valve to its original position. When you do locate the correct valve fill the system to 1 bar when cold. Then bleed your rads again and top up the pressure as it drops.

It is possible that it may be dirt blocking the rad or it may be that the inlet/outlets of the rad in question are blocked. A complete drain down may shift the dirt. But there is no point in draining unless you can refill it.
http://www.gasapplianceguide.co.uk/central_heating_systems.htm
http://www.britishgasacademy.co.uk/files/pdf/game_bbc.pdf

JamesM · 09-05-2006 9:38am

Ben77 wrote:

Hi,
Looking to see if anyone could help answer a problem that I am having with my heating – i.e. my radiator downstairs in the kitchen is not working. All the rest are fine.
Thanks.

It is most likely the thermostat.
See if the body will lift off or screw off.
You will see a small pin sticking out of the base. Sometimes this pin gets stuck in, blocking off the flow of water through the rad. Tap it gently on the top and it may pop out. therwise pull it with a pliers, then tap it. It should be free enough to be pushed in and will come back out on a spring. Also make sure that you have enough water in the system as already advised by the others.
Jim.

Ben77 · 09-05-2006 10:20am

Thank you both for those detailed replies.

I will try later what you mentioned.

Last night I noticed two taps under the boiler,
1) Water return
2) Heating flow
I tired to open the heating flow to raise the guage but it did not.

I know there is a feed underneath the sink so I will try that.
I think there is one aslo in the hot press so I could try that too.

Thanks again for your help.

JamesM · 09-05-2006 12:26pm

I had a quick look, but I can't see if you are talking about oil or gas. If your system is oil, I would not worry about the pressure. Once you have water when you bleed the upstairs rads, when the system is cold, then you are OK.
Jim.

Ben77 · 09-05-2006 12:41pm

Its Gas James. Thanks

JamesM · 09-05-2006 5:57pm

Ben77 wrote:

Its Gas James. Thanks

Some gas systems seem to shut down if the pressure in the system is not high enough. There is no danger, if there is enough water in the upstairs rads as I said above.
Jim.

Panic · 04-03-2007 2:10am

BEN77 ... DID YOU GET IT TO WORK ???

Alan.

Radiators / Heating

Comments