Gas central heating problem

[Lynne]

hello, we moved house very recently. 10 radiators in property. Gas boiler is a British Gas 330 Condensing Boiler (just been serviced). problem is if water and heating are on together, one radiator will not get warm, if heating only, all radiators function. Husband has bled system etc.
Any advice would be much appreciated. Thank you

 

[chris watkins]

This is not unusual as modern cylinders take so much heat (they can reheat themselves in around 30 mins) that there is not enough to do both at the same time.

Recommend that you set your programmer to have the boiler come on to heat the hot water only say 30 or 40 mins before you want the heating on (first thing in the morning), that way the cylinder will be switching off on its thermostat as the heating side opens.

BTW welcome to the forum

 

[joni os]

As above, also modulating boilers have "brain" of their own which can exasperate problem. Keep heating and hot water times separate.

 

[Knappers]

I agree.
Balancing radiators may also help, if you have any that are always stinking hot then turn the 'non adjusble' valve down 1/4 turn with a spanner.

 

[stevetheplumber]

i would also find out if you have a balancing valve on the cylinder which may need shutting down it will be on the return from the cylinder
if you havent got one this is the problem as all the flow will be racing round that circuit

 

[Unregistered]

thank you so much for your responses - worked immediately. very grateful.