Hi, I noticed that some of my radiators in the house does not get hot, could someone pls tell me what is the problem? I have tried briefly adjusting the lockshield valve (open fully on the radiator not getting hot) but to none effect. Any ideas pls?

has the system worked properly before, in prevous years?

maybe the pump is slow?

maybe the system is sludged up?

maybe the gas supply is weak, (restricted inlet filter, faulty meter govener)?

Hi, yes all the radiators have been working before - the radiators that are not working now have not been turned on for atleast 6mths to 2yrs/more. What should I check?

Do they have thermostats on the radiators?

you could also try turning off all the hot rads & the hot water, to try shift an airlock, maybe that'll cure it.

Have you bled the rads?

is it a combi? or a traditional system, with a cylinder?

Do you have a header tank?

Hi, no thermostat on radiator just ON/OFF turnings on one side and lockshield valve on the other.

I didn't understand your second point ("you could also try turning off all the hot rads & the hot water, to try shift an airlock, maybe that'll cure it.")

I have bled one of the radiator that is not getting hot but no joy.

my system is a traditional system with header tank.

On one of the radiator upstair (radiator not getting hot), I noticed that the 2 pipes (going to the ON/OFF & lockshield valve) on both side of the radiator is getting warmer (like it's getting hot water) but the radiator itself is not getting warm thou?

Also, around 2003 we had a plumber round and changed the boiler main heating system (not a whole boiler but the burning side of it - it cost half the price of new boiler £350 to be exact) the fault was that the boiler was leaking hence no heating. I'm not quite sure whether he changed the pump as well or not . Do you think it could be my pump that is at fault?

yes, maybe the pump is slow... but first try

switch the hot water off on the programmer

switch on the central heating.. let the system heat up.

on all the hot rads, turn off the wheel head valves, so the rad is now turned off.

this should them force the pump to supply water to the cold rads.

once the rads are fully hot, open the other wheel head valves on the rest of system.

Hi, firstly I apologised I was too stupid. From your previous msg "Do they have thermostats on the radiators? " yes they do (ON/OFF turns with numbers 1-5).

Tonight I have tried your instruction from last msg you posted, by closing all hot radiators lockshield valves and thermostats fully OFF on the whole house (except on one radiator which I couldn't get to & I don't know whether this rad work or not, but the thermo is definately off) and open all on cold rads, switched on central heating boiler on (pls note my programmer on boiler have 2 options only - ON for either hot water only or both heating & water) waited for more than 30 mins but no joy.

It's strange I found, the kitchen rad is working which we hardly switched it on since we had the heating system installed??

Any further advice pls?

if you have thermostats, then the chances are, the pins are stuck inside.

remove the head, from the valve (no water)... press the pin down, it should spring up.

If it doesn;t then the valve is stuck... try lightly tapping the pin with a small hammer, hopefully it'll pop up!

Hi, thx you for your reply. When you said "remove the head, from the valve (no water)... press the pin down, it should spring up. " Do you mean the thermostats or lockshield valve end? and (no water)???

the thermostatic head... leave the locksheilds as these (might) be balanced, so the system heats up evenly.

Is there any writing on the TRVs? Or can you post a picture?

there are many different types, and the heads all come off differenly.

Pictures attached.

Hi, THX YOU VERY MUCH - much obliged. It was the pin on thermo now all cold rads are hot again, so thx you for your guidances you're a saint.

Nice one Hinton.

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The CH God Strikes Again

Hinton, just for future reference when the warm weather comes back (I like looking ahead :grin: !!), what position should a TRV to left in to avoid (if possible) this sticking pin problem?
Is there a rule of thumb, or does it vary by make and model?

Hoovie.

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I went to a bookstore and asked the saleswoman, "Where's the self-help section?"
She said if she told me, it would defeat the purpose.

I'd say turn them to normal temp (number 4) would be good, to try make the pin move as theh temp goes up & down betweent he day & night...

If they are left low or on frost chances are they'll stick off.