Is this a sign my heating has a leak? Pressure dial drop

[zenonithus]

Hello all, I recently refitted a radiator after decorating. I then went around and bled all the radiators as they were not heating up properly. After I had to add more water into the combi boiler as the pressure had dropped to zero on the dial due to the bleeding. So I filled it up just over 1 and all was good. heating is nice and hot.

Though I noticed yesterday the heating isn't getting as hot. I bled only a tiny bit of water out of one radiator, though now the dial indicated the pressure is below 1, almost halfway to zero!

I don't know a great deal about how this all works so my only conclusion is that water is leaking from the pipes under the floor? If so I need to check asap as I have the carpet fitter coming soon.

Can anyone offer any advice? Cheers

 

[zenonithus]

Also just to add, the radiator I put back on after decorating, it works great though when I set the Thermostatic Radiator Valve to 1 or zero the radiator is still hot or still heats up. I think the other Thermostatic Radiator Valves on some of the other radiators don't turn the heating down either.

 

[jackthom]

Make sure you set up the correct pressure with the filling loop when the system is cold.
Then keep a check on how the pressure changes while all the radiators are heated up to full temperature.
If it is rising close to 3 bar when hot you have a problem with the expansion vessel and some water could have been lost previously via the Pressure Release Valve.

 

[zenonithus]

Hey jackthom, cheers. I do have two of the radiators turned off in the living room. Do I need to put those back on to check the pressure? Will have a look and see that the pressure is when cold then fill back to just over 1.

 

[jackthom]

Probably best to have all the radiators on while you are checking for the rise in pressure.
The water in the system expands as it heats and the expansion vessel allows it to do this without the pressure shooting up too high.

 

[zenonithus]

Interesting. I had no idea what an expansion vessel was so thanks for the info