New radiaters not working

M

maryrose

Registered User
Messages
55
I know this is not a seasonal topic, please bear with me , I know sweet sugarall about central heating, and I want to solve this problem before the winter returns.
We have oilfired central heating, and last Winter three rads., upstairs were replaced, apparently the exosting ones were corroded. The burner/boiler was also replaced. It had started giving problems , not firing up , you could never rely on it to work, I was convinced it chose the worst days of the year to go on the blink.
All of the above were approx in the house twenty five years.
Now , the problem is, those new rads., are not heating up sufficiently, they are tepid to cold, despite bleeding, balancing, and various procedures that plumbers use to coax rads., into performing.
I have been told that an airlock in the system , is the problem. I have also told that the heat is going to the immersion.
Have I got that right?
My main problem is that I dont know what questions to ask, is there anything I can do before Icall out a plumber again.
The guy who installed the rads., promised to return and "balance the rads" and never came back.
Two plumbers later, and we still have the same ole problem.
I dont want to turn this into a rant against plumbers, I just need help to understand whats gone wrong, so that I can at least see what the difficulty is .
thanks in advance to anyone who can offer a suggestion or give me an idea how best to solve this problem
 
oh rant away everybody else does.
Just as an idea was the boiler that was replaced the same size as the previous one?
anway
a) turn off all the other rad to see if these will heat up then, if not then there may be an airlock , if they do heat up maybe the boier isn't up to the job of heating all radiators.
b) there should be a stopcock on the feed going into the cylinder if you want to cut down the heat going to the cylinder, it works the same was as for the rads , close it down a bit to help balance the system.
c) bleed the radiators to release any air in the system
 
Re: New radiators not working

We had a similar problem with 1 radiator which got barely luke warm when all the rest were fine.

It took us 3 months of constant calls to the builder in winter to get his plumber back to the house.

He eventually came and discovered that the plugs, which come with the radiators from the manufacturer to stop dirt getting inside, had not been removed on this one radiator and this was what was causing the problem. Apparently it was fitted by an apprentice and wasn't checked.

Hope you get it sorted maryrose, beldin's advice seems sound.
 
With an older system of pipework there may be some sludge/ scale in the system. In severe cases this can affect valves, especially thermostatic valves. Or there could be a blockage caused by jointing compound, dirt etc..Firstly I would check each rad in turn, are control valves fully open, turned up high in the case of TRVs. Check that lockshield valves (valve on opposite side to control valve) are not fully closed. Buy a radiator bleed key, costs about €1.50 and bleed rads yourself when water is hot. Failing this the system should be drained down and flushed through to remove any potential blockage....Heinbloed may have some other suggestions.
 
we had a new system put into our last house and no upstairs rads were heasting. Eventually i figured oin an airblock. So I opened one of the rads for bleeding. I put a bucket under it....and basically let the water come out the bleeding opening into the bucket. After about 10 mins there was a big spurt and nocie etec....I guessed that was the air popping out. All of a sudden then the water coming out became warm. And I didn't have any trouble afterwards.

In our new house I am having fierce trouble again with upstairs rads. I have to bleed them at least once a week and am letting out a lot of air. I have no idea what is wrong with this....

Wheres heinbloed when you need him!
 
Legend99


If there's air getting into your system you have a leak(s) my friend! Try this, run your system for 15/ 20mins to get the circulating water up to operating temperature, turn off and allow to cool a little. Go up into attic and check expansion tank (smaller storage tank). Lift cover and see if the ball cock is filling at all. On a leaktight, well designed system the ballcock should rarely operate at all except to make up a drop in levels caused by evaporation from the tank. When the system cools down a weeping joint will allow air to enter. Potential problem areas are bad joints on the bleeding vents. Again you might see water dribbling/ weeping from a vent that doesn't seal properly, try removing it a wrap a strand of PTFE around it before replacing it. Other notorious problem spots are the actual rad valves. Check all for leaks and remember a leaking valve is probably leaking around the gland nut (where the stem is). This can be tightened or else remove and wrap some PTFE around stem before refitting. If all above fails a pressure test on the system will help to diagnose any fault.
 
Legend99

A small postscript, don't ignore air getting into your system it's bad for the steel parts of your heating circuit (boiler, rads etc) and corrosion can get a hold. Venting of rads on a good system should only be necessary about once a year, I think
 
Carpenter said:
Legend99

A small postscript, don't ignore air getting into your system it's bad for the steel parts of your heating circuit (boiler, rads etc) and corrosion can get a hold. Venting of rads on a good system should only be necessary about once a year, I think
Click to expand...

i know...i'm chasing the builders over it. Clearly the system is in trouble because if you bleed upstairs without doing downstairs the system will not work...its obviously out of balance or something
 
Carpenter said:
Legend99


If there's air getting into your system you have a leak(s) my friend! Try this, run your system for 15/ 20mins to get the circulating water up to operating temperature, turn off and allow to cool a little. Go up into attic and check expansion tank (smaller storage tank). Lift cover and see if the ball cock is filling at all. On a leaktight, well designed system the ballcock should rarely operate at all except to make up a drop in levels caused by evaporation from the tank. When the system cools down a weeping joint will allow air to enter. Potential problem areas are bad joints on the bleeding vents. Again you might see water dribbling/ weeping from a vent that doesn't seal properly, try removing it a wrap a strand of PTFE around it before replacing it. Other notorious problem spots are the actual rad valves. Check all for leaks and remember a leaking valve is probably leaking around the gland nut (where the stem is). This can be tightened or else remove and wrap some PTFE around stem before refitting. If all above fails a pressure test on the system will help to diagnose any fault.
Click to expand...

I have checked all the rads....none are producing water visibly. Either at the valves or the bleed joints. So I am getting seriously worried about a leak in the piping system...but I have been keeping a very close eye on all the plaster and there is no evidence of any wet patches etc so I am really lost.
 
legend99

Ask your builder to give you a gallon of Fernox while he's at it, at his expense if you can! It's about €35 in anycase.........
 
legend99 said:
I have checked all the rads....none are producing water visibly. Either at the valves or the bleed joints. So I am getting seriously worried about a leak in the piping system...but I have been keeping a very close eye on all the plaster and there is no evidence of any wet patches etc so I am really lost.
Click to expand...

Check the expansion tank as previously suggested (presuming your system is a vented system) Try bleeding system again and then check all rads again for leaks, there may not be sufficient water in the system to enable detection (esp. if a leaking bleed vent (high up, no water just air?). The leak may be more of a weep than a big leak. Either way it would be in your interest to rule out the obvious before the plumber does come, otherwise you might be plamed off with the old "it was just a small leak on this rad, gave it tweak, wont give you any more bother.." until about a week later, then it's builders holidays etc. don't get too disheatened whatever you do It's probably simpler than you think and under your nose. The plumber won't have a magic bullet either, he'll just have to rule out the obvious in an effort to fault find.
 
Carpenter said:
legend99

Ask your builder to give you a gallon of Fernox while he's at it, at his expense if you can! It's about €35 in anycase.........
Click to expand...
I think he left container of some anti corrosive stuff behind so obviously never added it to the system.

Yea, i can get the system up and running and check the expansion tank. At least if I see this filling I'll know for sure there is a leak. I'll check in detail the bleed joints and pipe valves. is it possible that one of them might be letting air leak in but no water be coming out...in that case its impossible I take it to find the issue?
 
legend99 said:
I think he left container of some anti corrosive stuff behind so obviously never added it to the system.

Yea, i can get the system up and running and check the expansion tank. At least if I see this filling I'll know for sure there is a leak. I'll check in detail the bleed joints and pipe valves. is it possible that one of them might be letting air leak in but no water be coming out...in that case its impossible I take it to find the issue?
Click to expand...

It is possible that air gets in and no water gets out, think about it. Warm water expands, when your system cools down the now cooler water contracts within the radiator, boiler etc. In doing so it creates a vacuum, if there is an air entry point, such as a leaking valve etc this is where the air will enter. If your radiators are filled mostly with air the water level will not be high enough within the rad to reach a potentially leaking vent bleed tappet (vent points are located at top of rad) so you will really have to bleed all rads to get the system fully topped up and then begin your detective work.b Good hunting........
 
maryrose said:
I know this is not a seasonal topic, please bear with me , I know sweet sugarall about central heating, and I want to solve this problem before the winter returns.
We have oilfired central heating, and last Winter three rads., upstairs were replaced, apparently the exosting ones were corroded. The burner/boiler was also replaced. It had started giving problems , not firing up , you could never rely on it to work, I was convinced it chose the worst days of the year to go on the blink.
All of the above were approx in the house twenty five years.
Now , the problem is, those new rads., are not heating up sufficiently, they are tepid to cold, despite bleeding, balancing, and various procedures that plumbers use to coax rads., into performing.
I have been told that an airlock in the system , is the problem. I have also told that the heat is going to the immersion.
Have I got that right?
My main problem is that I dont know what questions to ask, is there anything I can do before Icall out a plumber again.
The guy who installed the rads., promised to return and "balance the rads" and never came back.
Two plumbers later, and we still have the same ole problem.
I dont want to turn this into a rant against plumbers, I just need help to understand whats gone wrong, so that I can at least see what the difficulty is .
thanks in advance to anyone who can offer a suggestion or give me an idea how best to solve this problem
Click to expand...

"I have been told that an airlock in the system , is the problem. I have also told that the heat is going to the immersion."

Yup sounds like a problem I had when I first moved into my house first there was no hot water getting to the immersion due to air lock so a plumber friend of my Dads had a look and advised that the feed to the immersion was airlocked so he cut the pipe allowing the air to escape and replaced with new piping problem solved or so we thought, next problem was that the immersion was taking too much hot water and so we had loads of hot water on tap but the rads upstairs were only barely lukewarm to solve this the plumber put a valve on the main feed pipe to the immersion and half closed it thus stopping the immersion from taking too much of the precious hot water problem solved hot water on tap and hot rads upstairs.
Maybe worth mentioning to the next plumber to have a go.

Good Luck ;)

 
Hi folks ,
Thank you all for the replies, much appreciated.

The boiler is compatible with the previous one. I did check that out.
The system has also been drained and flushed , and as far as I can recall some type of chemical was used. This was done prior to the installation of new rads.,and this was whaen the upstairs rads., were pronounced less than fit.
Carpenter, if you are reading this , your information has led me on a process of elimination so far, and yes I have been bleeding all the rads., I am wary of checking the valves, in case I scupper the whole lot!

This is a real basic question I know, but do I turn clockwise or anti-clockwise tomake sure theyre not fully open as you suggested.

There are no leaks visible at any point in the system.
I have not checked the expansion tank yet, but thats next on the list! Not looking forward to climbing into the attic.
 
Hello Mary Rose

With any valve remember it's just a tap, so turn clockwise to turn it off, anti clockwise to turn it on. If a valve is particulary stiff try tightening/ loosening it first before turning it in the direction you require, this will loosen any scale which can seize up the moving parts. Best of luck in the attic!

Carpenter
 
You must log in or register to reply here.
Back
Top