Radiator not heating up

[Jimmychan]

Hello,

I have 3 radiators in the ground floor and 4 radiators in the first floor. The 2 ones in the ground floor is not getting heated while others are working fine. I can feel the hot water in the incoming pipe until it connects to one of the failing radiator. I read from this forum that some air may be in side, but i couldn't find the air bleeder at the top corners of the radiator. Can see something similar next to the thermostat at the bottom end. Please some one can give me some advice.

Thanks,

Jimmychan.

 

[Bahco]

Run your finger along the back of the top of rad. You should feel a bump which will be a plastic cap which you remove exposing the bleed valve.
Use a rad key to bleed and top up system (if required) if it is a sealed system

 

[bathjobby]

Jimmychan, what you are seeing at the bottom of the rad is the drain. All air bleeders are at the top (as air rises). If you have old cheap rads with the rounded top about 1/2 " thick, then the air bleeders are indented in one end just under the rounded top. If you have something different, try to describe what you have.

 

[Jimmychan]

Thanks very much for the replies, it really helped me to locate the bleed valve. But it appears there is no air at all in the rad as the moment i opened it, water started coming out. Is it something else causing the rad not to heat up?

Thanks,

Jimmychan.

 

[Nillbymouth]

I had similar problem with one of my radiators which took about 4 hours to get slightly warm. Turned out to be a sticking thermostatic valve. It might also be worth checking the lockshield valve.

 

[Jimmychan]

Any suggestions on how i go about this sticking thermostatic valve?

Thanks to all,

Jimmychan.

 

[Bahco]

With the heating on turn TRV to highest setting then remove the head.
Gently tap the central pin and this should do the trick.
I had to do this yesterday.

 

[Jimmychan]

A big thank you to all who responded and helped me to identify the fault. The culprit was the sticking thermostatic valve!

Well done mates,

Jimmychan.