Setting a frost stat

[macthebike]

Hi,
I have afrost stat in the garage near to my Glow Worm Compact boiler.
It is a Honeywell Frost stat, a plastic rectangle with removable front panel.
What you see inside is a circular dial marked 0 to 20 with a blue arrow at 3.(presumably a good temp for the boiler to switch on) The dial can be turned, but there is no obvious marker behind it to align the readings with.....So how do I set it ? Anyone met this type of Frost stat ?

 

[namsag]

set pointer straight up

 

[macthebike]

Hi namsag and thanks for "pointer up" advice.

I see from my Honeywell manual that the boiler has an internal frost protector which circulates hot water when the critical temperature occurs.

So I am wondering whether the Honeywell stat I described is really necessary, especially if the pipes around the boiler are well lagged. The trouble is that when it comes on it stays on for many hours, presumably waiting fo the air around the stat to warm up, which is a very long process in a cold garage...even near a boiler.
Do you think the internal frost tat plus good lagging is enough ?

 

[kippy]

Hi
Your problem seems to be exactly the same as mine: Glow worm boiler with Honeywell frost stat, both in the garage. The topic link to me is:

//www.diynot.com/forums/viewtopic.php?t=162468

Basically Glow Worm tech support have said the same as Dangermouse (in my thread) - it is OK to remove the frost stat as long as the pipes are well insulated. This morning my heating installer has come and done just that; if I have further issues he says he will then come and install a pipe stat.

Kippy

 

[Georgie01]

Hi

It seems i have a similar problem. I have a Potterton Puma Combi boiler. It is situated in our loft, pipes lagged etc. The external frost stat is cutting in and the boiler is firing up every 50-60 seconds. The rad's without thermostats are boiling hot and the only way to turn the heating off is to do it by the main switch.

British Gas came out yesterday and turned the frost stat (honeywell) to plus 3 from plus 5. Also he told me to take it off the wall and screw to the rafter or a piece of wood. This has been done, but seems to have made it even more sensitive.

Is it normal for the boiler to be firing up constantly all through the day and night?

 

[kippy]

My suggestion in the first instance is to contact Potterton tech support for advice. You may be able to run the boiler without the frost stat, providing the boiler has its own in built protection. My understanding is that modern boilers are more efficient so they produce less waste heat. This could mean that your loft is colder (this is the case with our garage) so the frost stat kicks in more readily. Ironical isn't it - you buy a more efficient boiler so it is in use more that the old one when the weather is cold. In my opinion, moving the stat is unlikely to have much impact unless it is placed on a warmer surface, but doing this defeats the purpose of the stat.
It gets hot in the house at night when the boiler is running! Overnight I manually turned off our rads that don't have thermostats (more convenient than turning everything off, and safer since the boiler can prevent pipes from freezing).
Kippy

 

[Georgie01]

Hi

Thank you.

Working fine last night, but it wasn't as cold. We are thinking of moving the boiler down stairs for next year, as we get this every year!