Boiler shuts down if both heating and hot water turned on...

[sestcourt]

Hi,

I wonder if anyone can shed some light on my little problem.

If the hot water is on with the heating off I get hot water to the tank, if the heating is on and the hot water off I get hot radiators. If at anytime I turn on both the hot water and heating the boiler quits and I have to revert back to only using either the hot water or the central heating....

We have British Gas F1 boiler, a Drayton 3 Position Flow control valve and a Drayton LP722 Control box.

Any help welcomed!

Steve

 

[ChrisR]

You probably need a new valve, but without testing with a meter it's a guess.

 

[sestcourt]

I did try putting the valve to manual and when I pushed the lever to the heating position it blew the 3Amp fuse for the system... So you might be right.

What should I get in the way of readings if I meter it out?

 

[D_Hailsham]

What should I get in the way of readings if I meter it out?

See How a mid-position valve works