Boiler frost stat

eddiej

Hi all,
Have a VOKERA think that is right gas boiler and it is in a little shed built onto the house (new build in estate). There is a frost stat located there and the boiler comes on when it gets too cold to make sure the boiler dont freeze I suppose anyway the stat goes from 0 degrees to 15 degrees obviously the lower I set it the more I will save as the boiler wont come on as often but how low can I set it without damaging the boiler. Any help as always greatly appreciated

eddie

crosstownk

While I can't tell you what temeprature to set it at, I do know that some manufacturers supply a frost stat that is unadjusatble and set for +6C. Personally, I wouldn't set it for any less than 3C. Be sure that all the pipework is lagged - very important.

Hope thats of some help to you.

JamesM

eddiej wrote:

Hi all,
Have a VOKERA think that is right gas boiler and it is in a little shed built onto the house (new build in estate). There is a frost stat located there and the boiler comes on when it gets too cold to make sure the boiler dont freeze I suppose anyway the stat goes from 0 degrees to 15 degrees obviously the lower I set it the more I will save as the boiler wont come on as often but how low can I set it without damaging the boiler. Any help as always greatly appreciated

eddie

It's a "Frost Stat" Its purpose is to stop the water in the boiler freezing. Water freezes at 0 degrees, so set it at 0 or 1. If you want to use it to keep the house always at a reasonable temperature, then keep it higher. Although you may find that it only controls the boiler (to stop it freezing) and may not turn on the circulating pump.
Jim.

crosstownk

Be careful - ice particals can begin to form in water below 4C (at 4C water is at it's most dense). Remember the frost stat is measuring the ambient air temperature and not the water temperature in your heating system. So it could be possible, depending on conditions, that your water could actually be colder than the ambient air temp (more likely if the heating has been off for a time - eg while you are on holidays). IMO it's best to leave a bit of 'headroom' and set it to at least 3C.

JamesM

crosstownk wrote:

Be careful - ice particals can begin to form in water below 4C (at 4C water is at it's most dense). Remember the frost stat is measuring the ambient air temperature and not the water temperature in your heating system. So it could be possible, depending on conditions, that your water could actually be colder than the ambient air temp (more likely if the heating has been off for a time - eg while you are on holidays). IMO it's best to leave a bit of 'headroom' and set it to at least 3C.

I won't argue with you - it's always better to be safe !
Although, if the air temp is above freezing, what brings the water temp in the boiler below freezing ?
Jim.

crosstownk

JamesM wrote:

I won't argue with you - it's always better to be safe !
Although, if the air temp is above freezing, what brings the water temp in the boiler below freezing ?
Jim.

Drafts are one example - although it questionable as to whether these ice particles can cause damage to the heating system But as you say better safe than sorry!!! I wonder is there any sort of "anti freeze" that can be put into the system to protect at lower tempertures - similar to a car engine? Obviously the system would have to be a sealed, pressurised system.

JamesM

crosstownk wrote:

Drafts are one example - although it questionable as to whether these ice particles can cause damage to the heating system But as you say better safe than sorry!!! I wonder is there any sort of "anti freeze" that can be put into the system to protect at lower tempertures - similar to a car engine? Obviously the system would have to be a sealed, pressurised system.

I think that the Fernox anti corrosion additive has some anti-freeze properties.
Jim.

crosstownk

I must look into that as my boiler is in the garage which gets brass monkeys on cold nights and I've no frost stat. I'm sure that with the correct amount of anti-freeze the frost stat could be taken down by another degree or two.

JamesM

crosstownk wrote:

I must look into that as my boiler is in the garage which gets brass monkeys on cold nights and I've no frost stat. I'm sure that with the correct amount of anti-freeze the frost stat could be taken down by another degree or two.

Something like that: http://www.plumbworld.co.uk/93-770

eddiej

Thanks for all the help lads have reduced the stat to 5 degrees it was at 15 thanks again

Eddie