Gas heating problem....

skye

Hi all, have recently moved into a new house which is connected to gas mains for heating. My problem is that the heater in the sitting room is only slightly warm when on, but all the other heaters in the house are scorching.... Any ideas how to remedy this?? Do you "bleed" gas heating? If so how? Any help appreciated & thanks!!

Dilbert75

AFAIK, it should make no difference whether your central heating is fuelled oil, gas, coal or cow dung - the water still pumps around the system in a similar way. The radiator in question - is it an even temperature throughout or is it hotter or colder at the top or bottom? If its an even temperature, check that the valves on the inlet and outlet are fully open - even if it looks open, it may not necessarily be.

If its colder at the bottom, it could be that this rad is at the end of the system, so you need to turn down the heat in the other rads a bit, so the water is a bit hotter when it gets to this rad. This usually only happens where its a big system though and the boiler is not adequate to heat the volume of water.

If its colder at the top, it's probably air. This could be for two reasons: needs to be bled or the system needs to be filled.

To bleed the system: There's a little bleed screw at the top at one end - either you can use a special little square shaped key (available from any hardware shop) or sometimes you can use a flat bladed screwdriver. With the nut covered with a piece of kitchen paper, crack open the screw (don't remove it) and listen for a hissing sound - this should indicate the air escaping. As the rad fills, the hissing will stop and it will start to spit from the bleed screw. Close the screw at this point, before the paper gets soaked and the water stains your wall or floor (it will likely be black).

If your system is a sealed system (where there's no header tank) it may need to be topped up (as a result of either a leak or the pressure relief valve allowing some water to escape). There should be a fill valve, poss in your hot press, to allow this to be refilled. Open the bleed valve a crack, gently open the fill valve and allow the system to fill till you hear it bubbling at the bleed valve. In my OFCH system's case, I then close the bleed valve and keep the fill valve open until the pressure gauge in the boiler reads 0.5 bar. A GFCH system might be different though - get a pro's advice on this.

garyh3

I have the exact same problem.

All but one rad is hot ... its cold but the pipe leading into the rad is hot. The valve I think is open and when I turned the bleed valve water came out.

The boiler is at 1 bar going to 1.5 bar when the boiler is on. Upstars all the rads have thrimostats on them and down stairs there is thirmostat in the hall.

Is there anything else to try.

Grayh3

Dilbert75

The thermo valve only controls the inlet - could the outlet valve be closed? Have you tried closing all the other rads and see what happens to this one?

skye

Thanks for the response - will try these options and let you know how I get on....

stag39

garyh3
quote<<I have the exact same problem.

All but one rad is hot ... its cold but the pipe leading into the rad is hot. The valve I think is open and when I turned the bleed valve water came out.>>quote


hi garyh3...
had this problem before......unscrew the thermastatic vavlve an if the thin needle like nipple is still nearly all the way in get a pliyers an gently grip the little nipple an pull upwards... when it comes up.. push it back down an up a few times....this will without a doubt solve your cold rad problem....

the nipple gets stuck from the rad being turned off for long periods...

stag

garyh3

Found the problem and now fixed. Its a new house and the builders are still on site. Told me to unscrew the rad from the inlet end and let some water out+air, as the rad pipes come down the wall so I have to watch where I put pictures!.

Did this then went and added back the water into the system. and now rads nice and hot.

regards

Garyh3

skye

Thanks Dilbert75 - problem solved with a simple turn of knobs!! Cheers!

Dilbert75

The best solutions are often the cheapest!