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Brian, HVAC Technician
Category: HVAC
Satisfied Customers: 869
Experience:  OFTEC registered oil heating engineer and plumber.
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Hi Brian, I read with interest the thread about the lp722.

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Hi Brian, I read with interest the thread about the lp722. I too have a tripping problem which started sporadically and I isolated down to the heating timer circuit. I too have a glowworm boiler a gas boiler (hideaway 50) and wondered whether I might have a similar problem! Any advice would be gratefully received
Hi I notice you say you removed the timer do you mean you have changed it. The heating circuit tripping a fuse is most likely to be water pump or motorised valve, least likely to be boiler or programmer

But as you have seen from reading other threads intermittent failures could well mean it's a programme fault. How often does it happen

Customer: replied 3 years ago.

I haven't changed the timer recently, and it's a very simple gravity fed boiler. I hadn't considered the pump, which is very old, but hasn't given me any problems. He while installation was here already when I bought the house 5 years ago. How would I be able to check the pump is the culprit?


Many thanks

How often is it tripping. The easiest way to check if it's the pump is to disconnect it, just a live neutral and earth.
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Customer: replied 3 years ago.

I couldn't pin down precisely how many times it trips, but it went from intermittent to constant within 2 days. I have isolated the central heating timer and the rcd is now fine. I can't

Get to the wiring on the pump as it's underneath the cylinder! I've called a heating engineer.