Wrong pipe stat?

We have a Grant Vortex Eco oil boiler, installed about 2 years ago in an unheated utility room. The heating comes on on cold nights for frost protection, over-riding the timing and thermostat controls. The problem is that it is on for much of the night, staying on for about for about half an hour at a time and the radiators get super hot. This seems excessive just to stop the pipes from freezing and must be costing us loads.

Based on a bit of googling, reading forum posts and comparing to our set up, I think we have the wrong pipe stat fitted. It is a Honeywell L641B1012, which goes from 50-95C. Seems like we should have a L641B1004, which goes from 10-40C. Then the boiler would switch back off once the water is warm enough to avoid freezing, rather than heating the whole house all night.

It looks easy enough to switch out. But as I know nothing about central heating, whereas the person who installed it presumably did, I want to make sure I am doing the right thing. I obviously don't want to change it and end up with frozen pipes! Is there a reason why they would have installed a pipe stat with such a higher thermostat setting, or is this an installation error which needs fixing? I see in the manual that the L641B1012 is used for solid fuel systems, but should it also be used for an oil boiler?

L641B1004 is the one you should have fitted.

You have the wrong pipe stat fitted

As stated swop out with correct one.

I had one on my old wb 240rsf boiler based in the outback building, i noticed heating on during nights in the house during my first winter when i first bought the house.

I also had a basic thermosat in teh outbuilding set to 5c, teh pipe stat was set to 45c or something, however with this setup i calculated heating would be on all night during very cold winters, this was in 2004, over the years we had some colder winters, 2009 winter, 2010 winter, 2013 winter, however i set the thrmostat to 0 and the pipe thermostat to 15c. The boiler still fired on cold nights but did not mean i would be facing large bills with heating on for longer periods.

No damage was done to the boiler or the pipework, now i have no outback building, extension built, replaced by a main eco compact elite 30kw with proper heating controls and no need for pipe thermostats.

Thanks all. I thought so, but it's good to have it confirmed before making any changes.