Boiler works ok on CH but goes to lockout when hw selected

[armyash]

Hi guys

Just had a call from a customer, the central heating works fine but as soon as he turns off the ch and selects hw, the boiler locks out and requires a reset.

Any ideas? I am unable to get there until tomorrow evening.

It's S or Y plan, could it be a faulty bypass, div valve or no pump over run??

Just a couple of ideas. Baxi Solo 380 PF

 

[IDCHAPPY]

2 port or 3 port not opening would be my first port of call buddy.

 

[AWheating]

no circulation, boiler over heating. check gate/ balancing valve is open on coil before anything else.

 

[armyash]

Gate valve on coil pipe is open but looks worse for wear, said i will change that.

With CH off at programmer, rads still get hot when just on hot water. Motorised valve does not seem to be working as i switch between the hw and ch.

When just on HW the pump makes a bit of a racket and the vent pipe gets hot, if i stop the pump then start it again i can hear water shooting out of vent pipe and the pipe cools down.

CH seemed to be working fine.

 

[Mike Jackson]

It's a circulation issue. If all valves are opening correctly then possible blocked coil. This may be an instance where the Bg favoured PF is actually needed.

 

[bassmonster]

It's a circulation issue. If all valves are opening correctly then possible blocked coil. This may be an instance where the Bg favoured PF is actually needed.

what's BG and PF? :blush5:

 

[Masood]

what's BG and PF? :blush5:

PF is powerflush, the preferred option of British Gas to fix any and all issues.

 

[armyash]

cheers guys