Cold Radiator. Am I doing things right?

[tigers999]

Afternoon all,

I am just after some re-assurance that I am doing things correct and would really appreciate some tips or advice if needed.

I live in a 3 story town house, fairly new build (6 years) with radiators in every room. We have an ideal ICOS condensing boiler (He12 I think) and basically ever since we have lived here, the living room radiator never gets red hot like the other radiators. It barely gets luke warm to be honest which is why I have finally decided to address it.

A boiler repair man a few years ago said it may have sludge in which needs flushing but it was only a couple of years old at the time and it has never worked properly so I put that off (really wish I had flushed it now tbh though). My friend said it is maybe the last radiator in the system and therefore not getting hot enough but he isnt a boiler man so he was just guessing.

So today I have finally decided to start investigating the problem. Google here I went. A video instructed to make sure the lock shield valve is fully open on the radiator that doesnt work and then go around and turn all of the other radiators off. If the radiator heats up then go around and turn each radiator on one by one and see what happens.

I have done this and noticed when I went around checking the radiators that all of the "lock shield valves" were open apart from 1.

First question would be, should i open or close all of the lock shield valves during this test? They are all open at the moment but I am thinking they should be closed for this?

Second question is am I on the right lines? I am thinking that if the radiator does heat up that I should go about balancing the other radiators. If the radiator doesnt heat up, then its the radiator?

Thanks in advance. I will say all radiators have been bled. I will let you know if the cold radiator starts to heat up over the next hour or so

 

[tigers999]

Ok I am thinking after abit of reading this could be my main problem. If all of the lock shield valves were open then the last radiator (if it is infact the living room one) will not be getting as much heat!

How can I test if this radiator will heat up fully before I buy a digital thermometer to balance the system?

I am trying now to heat the radiator like above but it isnt getting hotter. I am guessing because I need to close all of the lock shield valves on the other radiators? I am abit reluctant to do this as they were all open and I dont like to change anything until I am told it is safe to lol

Thanks again

 

[tigers999]

Just for thread updating so people know where I am at lol

The radiator wasnt getting any hotter so I have decided to go around and close all of the lock shield valves apart from that one radiator to see if that heats it up.

If it does then my plan is to turn the heating off again and let it cool, and then go around opening all of the lock shield valves and turning all of the radiators on again. I will then start the heating again to try and figure out the order the radiators turn on. I have a suspicion so it shouldnt be too hard. Then I will proceed to try and adjust the lock shield valves to balance the system....by hand tonight and maybe a digital thermo if i find it hard.

If the radiator doesnt get hotter after shutting off the lock shield valves I guess I have just totally unbalanced my system for no reason but atleast I will know that it is the radiator lol

 

[TheVictorian]

Sounds liek a classic case of it just needing balancing.

I would also never use the plumber who suggested flushing the system.

 

[tigers999]

Sounds liek a classic case of it just needing balancing.

I would also never use the plumber who suggested flushing the system.

Thanks for the reply mate, really appreciated!

Yeah to be honest we never have again. He was a friend of a friend who was all but retired and to be honest I dont think he could be bothered to do anything to it so mumbled something about getting someone to flush it. As I said, I never got it done because I thought the system was too young to need flushing already!

Just now the radiator in question is getting slightly hotter....not much mind and it is considerably colder at the bottom still....to a point where it is cold...not even luke warm. Every radiator in the house apart from that is off now...surely this one, even if it was at the end of the line would be fully hot by now?

 

[tigers999]

Another thing I have noticed which may or may not be relevant.

The thermostat is "clicking" at 20C and has been for a few days. It doesnt matter how high you have it sat at 25C, 27C, it always always clicks at 20C. I am sure it used to click when you requested heat as such....could my thermo be stuck at 20C?

May sound a stupid question but could explain why the radiator isnt heating up anymore?

 

[TheVictorian]

You could also try removing the top of the TRV and make sure that the little pin is moving up and down correctly - sometimes they can get stuck.

I don't know about the thermostat, does the boiler turn off when it clicks or is it still on?

 

[tigers999]

You could also try removing the top of the TRV and make sure that the little pin is moving up and down correctly - sometimes they can get stuck.

I don't know about the thermostat, does the boiler turn off when it clicks or is it still on?

Yeah cheers mate, I ckecked all of the TRV's as I went around the radiators. All pins appear to be intact...I think lol

Its weird the thermostat. I cant really explain what I mean, erm lets say the thermostat dial is at 10C and therefore not on. The "click" on the thermostat would be at the temperature of the room that the thermostat is in. Lets say this is 18C therefore the heating will not come on until I set the dial to anything above 18C. I set the dial at 22C...the boiler then fires up until the thermostat (house temp) reaches 22C. If I then turn the dial upto 25 the "click" would have changed to 22 because that is the point at which heat is now being requested.

This is what normally happens...... but now the "click" is just staying at 20C regardless of what temperature the room the thermostat is in. I have just placed a thermometer ontop of the thermostat to see what it is reading, I will let you know the outcome. I hope that has explained things abit better lol

I am thinking that I have 2 problems. A broken thermostat and an unbalanced system! What do you think?

Thanks again

 

[tigers999]

Another interesting development. I have turned the thermostat right down to off and the boiler still fired up requesting heat?

I am thinking I have definitely inadvertently found another problem

I better add, we run the heating on the timer to switch off at 11pm and tbh the last few nights it has seemed almost impossible to heat the house up during the evening despite the radiators feeling hot. (not the broken one ofcourse but that is what I was putting it down to, hence me trying to fix it)

Could it be possible for the thermostat to stick on at 20C? Is it just a case of wiring up the 2 wires to a new thermostat?

Thanks again

 

[oldbuffer]

The thermostat will "click" at the temperature of the room. If the room is at 20 and the thermostat is at 25, turning it back to 18 will still make it click at 20. Likewise, if the thermostat is at 18 and you turn it up to 25, it will still click as its goes past 20.

Let the temperature in the room drop, then the click point should be lower.

 

[tigers999]

Thanks for the reply,

Yeah i have now figured out that the thermostat is working, false alarm. Now to figure out why the radiator isnt then lol

It is slowly heating up and is getting hotter at the top but the bottom still feels cool. I may leave it like this for another hour and see if it heats up. Then start turning the others on one at a time.

I am slowly moving between sludge and dodgy valve!

Cheers again

 

[Armo74]

To eliminate the feeling that it is a dodgy valve swap the trv head for another one and see what happens. To eliminate the chances of a possible build up of sludge take the rad off and flush it, Whilst the rad is off do the bucket test to see if you have a blockage.

 

[tigers999]

Thanks mate, that is tomorrows task I think!

I have now left all of the radiators turned off via the lock shield valves sending all of the heat to the radiator that wasnt working very well. I am pleased to report the top of the radiator has heated up quite abit. Nothing like I would expect though and the bottom certainly isnt heating up.

I am thinking the radiator at the very least is blocked somewhere.

I am now going to turn all of the radiators back on like they were and see what happens to the heat of the faulty one. Either way though I think I am going to have to take it out and flush it tomorrow!

 

[tigers999]

So, here we are at the end of a fun few hours.

I have now opened up all of the other lock shield valves and bled every radiator. FYI there was no air in any of them.

The heating is now on with every radiator appearing to be working fine.............apart from the same one in the living room. It is undoubtedly hotter than before so god knows whats changed but the bottom just isnt heating up still.

I think I should take it off and flush it out, what do you think? (not tonight though lol)

I dont see it being a balancing problem as it didnt heat up when all other radiators was turned off, does this sound right?

Thanks again

 

[Armo74]

Yes