How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Andrew Smith Your Own Question
Andrew Smith
Andrew Smith, Home Appliance Technician
Category: Appliance
Satisfied Customers: 3756
Experience:  Gas cooker specialist
Type Your Appliance Question Here...
Andrew Smith is online now

I have recently replaced an old Tempus 7 controller with a

Customer Question

I have recently replaced an old Tempus 7 controller with a LP522 in an attempt to cure the boiler and central heating remaining ON 24/7 despite varying settings on the controller and/or reducing the room thermostat temperature. The only way to switch CH off was to cut the mains supply to controller and boiler.
This has continued with the LP522 BUT the Tempus 7 was previously set to the 'G' position originally when all was OK - I am now unable to move the G/P slider on the LP522 from its supplied 'P' setting to the 'G' position, it seems locked in some way.
Is there a trick to move this slider OR can the programmer function, with eg. wiring changes, as it should but using its 'P' setting?
Or should I investigate the room thermostat?
Or what could be the cause of the original problem with continuous firing?
Many thanks in anticipation - Malcolm Davies.
Submitted: 3 years ago.
Category: Appliance
Expert:  Andrew Smith replied 3 years ago.
***** ***** : P stands for pumped
***** ***** : G stands for Gravity
***** ***** : this means when on G setting you cannot have heating only on, it will turn on the hot water also
***** ***** : it is all to do with the way it is wired and controlled
***** ***** : if you had continuous firing I would firstly check the motorised valve.
JACUSTOMER-j2cydk2y- :

Thanks for your time but that I know!! Main questions not really answered so poor sadly. Bye.

***** ***** : Have you checked you motorised valve then?
***** ***** : depending on the model it may be a removable plug or a screwdriver slot that changes the setting
***** ***** : do you have a picture of the rear of the programmer?
JACUSTOMER-j2cydk2y- :

Valve's OK. I thought I'd clicked on a Drayton specialist (no offence) so I'm waiting to speak to their tech help on Monday. Let's leave it at that :-)

***** ***** : The timer controls the motorised valve
***** ***** : the motorised valve controls the pump and boiler
***** ***** : if you have no lights on the programmer and the heating is still running then the motorised valve is still open