DIY Doctor

Main navigation

Faulty Frost Protection Thermostat?

Postby alant » Fri May 29, 2009 12:01 pm

Can somebody help me diagnose a problem? The hot water/heating has been working fine. Now no hot water (heating has been turned off for weeks now) - the only way I can get the boiler to fire up and heat the water OK is to turn the forst protection thermostat (range -15 to + 10) clockwise right to the stop when you hear it click as a thermostat does and then the boiler performs normally. I have had to tape the thermostat dial to keep the system working. Around 12 months ago a new 3 way valve and central heating/water main timer control was fitted. Can this be a faulty forst protection thermostat?
Rank: Labourer
Progress to next rank:
Posts: 1
Joined: Fri May 29, 2009 11:53 am


Simply Build It

Postby bd3cc » Fri May 29, 2009 9:18 pm

If you turn the Frost stat up, so that it clicks, it is closed and "calling", therefore I would doubt it is a faulty froststat.
Would look elsewhere, but you will probably receive more detail from others.
Rank: Foreman
Progress to next rank:
Posts: 323
Joined: Wed Jan 30, 2008 8:02 pm

Postby sparx » Mon Jun 08, 2009 4:00 pm

as bd3cc says it is not the frost stat at fault.
The frost stat bypasses all other controls so even if everything is off on timer if temp. drops very low it will call the boiler to prevent freezing.
I would guess timer may be faulty, or more likely if its a wall mounted type it is not tight on its back plate so not making contact with wiring, this is a freq. fault if difficult to get to tighten mounting screws at bottom of timer.
Rank: Project Manager
Posts: 2166
Joined: Wed Mar 21, 2007 8:33 pm
Location: The fifth continent.

Display posts from previous
Sort by
Order by

  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!

  • Related Topics