New house radiator not getting hot..

gamerdude1989

gamerdude1989

gamerdude1989

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Hey guys

Anyone work in, or have any knowledge in home heating?
I live in a small bungalow, that had an extension some years back, But they never installed any heating piping or radiators in that end..
So me and my mrs decided to have worken out, to come fit a radiator down "the bottom room"
BUt it just doesnt get hot?!?!?

Let me give you a run down of what i know...
2 copper pipes... One is the feed pipe, and the other is the return...
The feed pipe gets hot, But the return pipe stays freezing cold.
The radiator does get a very tiny bit of warmth.. By that i mean.. You can feel the top of the radiator isnt ice cold like the bottom of it.... But thats the extent of it...
All the other radiators in the house can be fully upto temp, to the point where they burn your hand...
But the new radiator.... Gives out ZERO heat...

I dont know their technical names... But one side of the radiator has the dial... where you can turn the radiator up and down.... The supply side...
and the other side... the return side, Has a small twist valve to lock it off....
Both valves are open....
I initially thought the return valve had been left shut off... Explaining why the return pipe stays freezing... NOPE...

The engineer did explain to me, that the heat is like a cake... Eat radiator has a piece... Turning one radiator down, Can allow others to get more heat.. etc..
SO... thinking that maybe adding this new radiator, was at its "max headroom".... I went round the house and turned down the radiators a little that dont need to be so hot....
"balancing the system", as they call it....
our living room is always cold, so that dial is on 5/5.....
OUr hall way gets real toasty, So i turned that down to 3 out of 5...
Same as our 2nd toilet (Yes, 2 toilets in a small bungalow.. stupidi know)
But we never use the 2nd toilet.. its more of a junk storage room lol...
So i turned that radiator fully off.... Again.. Thinking that turning that off, Will allow the new radiator in the "back room", to get the heat instead..... NOPE....

Any ideas please?
Our back room is a poorly insulated extension, and it gets friggin cold down there!!! (see your breath, sorta cold)...

Any ideas?

cheers
 
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Sounds like your radiators need balancing.
Closing the TRV like you have been doing won't slow the flow, until the room is at temp.
Close down the smaller valve will and allow more hot water to your new radiator.
 
Did they bleed the system after first run after adding the extra? could also be a stuck valve somewhere but I don't know much about that - sometimes it can have an odd effect on the system balance.
 
It strikes me you can rule your "balancing" theory in or out by turning every other radiator completely off. If your new rad still doesn't heat up, it isn't balancing.
 
rodders said:
Sounds like your radiators need balancing.
Closing the TRV like you have been doing won't slow the flow, until the room is at temp.
Close down the smaller valve will and allow more hot water to your new radiator.
Click to expand...
I know absolutely nothing about heating systems bud..I dont know what a TRV is.... So what i should try doing lol
 
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The TRV is the valve with the head installed on it with the numbers, with the numbers representing a temperature where the radiator will be cut off from water once that room is up to temperature.

The other side is the lock shield valve, this can regulate the water flow. This is the valve you adjust to control the flow of water to each radiator, the radiators that heat up the quickest (usually nearest to either the boiler or the pump depending on combi or not) usually have the valves open a 1/4 of a turn from the closed position. I.e. barely open.

What's the flow temperature from your boiler, and what is the temperature of the flow into the radiator that's not heating up?

Based on what you've said about the numbers in each room, it seems like you're incorrectly using the TRV to control the flow of the water to each radiator. TRVs only control the temperature at which they auto shut off (unless you set it to 0 which will shut it off completely, unless the valve isn't seating properly). You need to adjust the other side called the lock shield.
 
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Mekrel said:
The TRV is the valve with the head installed on it with the numbers, with the numbers representing a temperature where the radiator will be cut off from water once that room is up to temperature.

The other side is the lock shield valve, this can regulate the water flow. This is the valve you adjust to control the flow of water to each radiator, the radiators that heat up the quickest (usually nearest to either the boiler or the pump depending on combi or not) usually have the valves open a 1/4 of a turn from the closed position. I.e. barely open.

What's the flow temperature from your boiler, and what is the temperature of the flow into the radiator that's not heating up?

Based on what you've said about the numbers in each room, it seems like you're incorrectly using the TRV to control the flow of the water to each radiator. TRVs only control the temperature at which they auto shut off (unless you set it to 0 which will shut it off completely, unless the valve isn't seating properly). You need to adjust the other side called the lock shield.
Click to expand...
Ahhhh. im understanding you a bit better now...

The radiator that isnt heating up.. Has the Lock Shield valve set to wide up....

My boiler temperature is set for 65c...
Temperature flowing into my radiator? I have no idea... But the pipe gets HOT.... Just the radiator doesnt... and the return pipe stays freezing cold...
 
I've previously had exactly this, might be a stuck valve.
screw the top off the TRV, there's a little pin that can move up or down, push down on it with a flat screwdriver or something, does it move?

myboiler.com

How to Repair a Thermostat Radiator Valve (TRV) not working with TRV pin stuck

If your Thermostat radiator valve (TRV) is not working, more than likely the TRV pin will be stuck. To fix this carry out the following steps. Before you start, you should always make sure you car…
myboiler.com myboiler.com
 
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Rob_B said:
I've previously had exactly this, might be a stuck valve.
screw the top off the TRV, there's a little pin that can move up or down, push down on it with a flat screwdriver or something, does it move?

myboiler.com

How to Repair a Thermostat Radiator Valve (TRV) not working with TRV pin stuck

If your Thermostat radiator valve (TRV) is not working, more than likely the TRV pin will be stuck. To fix this carry out the following steps. Before you start, you should always make sure you car…
myboiler.com myboiler.com
Click to expand...
Ahhhhhh. I will try this shortly :)
Thankyou
 
gamerdude1989 said:
Ahhhh. im understanding you a bit better now...

The radiator that isnt heating up.. Has the Lock Shield valve set to wide up....

My boiler temperature is set for 65c...
Temperature flowing into my radiator? I have no idea... But the pipe gets HOT.... Just the radiator doesnt... and the return pipe stays freezing cold...
Click to expand...

It's more the other radiators, if they're too open then a good flow of hot water won't get to the radiators furthest from the heat source. However, if you're saying it gets hot then it's unlikely there's too little flow going to this new radiator.

Rob_B has a good point, the TRV could be knackered on the radiator although that would surprise me as I assume the radiator they've installed is new and so are the valves? Worth checking out though.

Check the pin as he says but ensure you don't pull the pin up with pliers. Only apply pressure down to see if it moves freely. The other thing to check and this actually occured on a TRV in the house we bought a year ago is to check the head of the TRV. There's a plastic pin inside that pushes the metal pin down to close the flow when the room gets to temperature the TRV is set to. Is the plastic pin moving freely? On ours it was permanently stuck down and therefore closing water off to the radiator no matter if it was set to 0 or 6.

The TRVs come off easily, they're usually screwed on by hand.

I don't think it's air as usually the radiator and return pipe would be hot, just the top would be cold. Worthwhile bleeding it though.
 
That was it :)
Just removed the TRV and noticed that the inner part was deformed.. Looking like excessive pressure...When it shouldnt look like that.. Its brand new
Under inspection... Even with the TRV set to 5/5.. it was still applying pressure to that pin, Keeping it pressed in!
Put the heating on to test the radiator without the TRV screwed on... and it got hot super quickly, Just like the other radiators in the house do..
(Small bungalow, So im gathering thats why the rads heat up so damn quickly)....

But yep... Got hotter within 3 mins of the heating being on.. without the TRV screwed on, that its even gotten!

Cheers guys....Not something id of ever thought of tbh....
A new item faulty from the get go.. Who'd know....
 
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