3 hot radiators, the rest are cold?

[FrancesDoesItHerself]

Hi, can anyone help me?

We have a fully pumped hot water and central heating system, gas fired not combi boiler type.

Yesterday morning when the heating came on only 3 of the radiators were working - first three on the circuit, all upstairs.

The obvious cause would be the pump, but it does seem to be working, it it hot, you can hear it (it's always been quite noisy) and when I started it up with the screw out you could see it going round.

We drained the system and refilled it with cleaning stuff in (since we were going to do this soon anyway, it's long overdue) and refilled it, still only these three work. If you switch off the three working radiators the next one (downstairs) comes on, then if you switch that off the one after comes on and so on up until the last three radiators (upstairs again) which do not heat up at all.

I have bled all the radiators and there doesn't seem to be any air in any of them, though the pump is collecting air and I am having to bleed it once every couple of hours.

Any thoughts?

Frances

 

[ollski]

Have you played with the lockshield radiator valves at all...sounds like a balancing issue. Or have you fully opened the bypass valve if you have one?

 

[FrancesDoesItHerself]

Could it get so unbalanced so quickly?

And what is the bypass valve?

Sorry for sounding dense, I don't know much about central heating yet!

Frances

 

[FrancesDoesItHerself]

Update on the above - I have cleaned the system out, plus taken the pump to bits and cleaned that, and still we have only three radiators coming hot.

The pump is definitely going round but could it be not going round properly ie fast enough to pump the water round? I am really not keen to change it unless I am sure that it is the problem, because it is in an awkward place and we've tried to get it off before with no joy.

Any other ideas? I can't get anyone to come out and look at it, having pretty much trawled through the phone book, and it's really cold in my house!

Frances

 

[breezer]

have you done as mentioned, turned all other rads off and bled the cold ones?

 

[FrancesDoesItHerself]

yes - there didn't seem to be any air in them.

 

[taydo]

hi did this problem happen suddenly or gradually?

I got a bit lost with the radiators are you saying that when you switch of all the working rads the other three get hot or not

 

[FrancesDoesItHerself]

It happened suddenly.

We have three radiators working and the rest not. When you switch off the three that are working, the next one comes hot. If you switch that one off, the one after comes hot. And so on.

Frances

 

[Completebeginner1]

Hi Frances,

Did you manage to get this fixed in the end? Can I ask what the magic solution was as we're suffering from the same problem, thanks!

 

[gavinda]

last post 6 march 2004