Boiler frost protection.
Discussion
My boiler is in the garage.
It has a manual thermostat fixed underneath it as well as one in the hall inside the house.
The garage thermostat is set at 2oC and can't be adjusted.
There's also a temperature sensor on the boiler output pipe set to around 60oC.
I've noticed that the pump in the airing cupboard is cycling on and off quite frequently and it seems to be independent of the HW or CH.
Is this likely to be some sort of frost protection circuit keeping water moving through the boiler / HWC loop?
Ta.
It has a manual thermostat fixed underneath it as well as one in the hall inside the house.
The garage thermostat is set at 2oC and can't be adjusted.
There's also a temperature sensor on the boiler output pipe set to around 60oC.
I've noticed that the pump in the airing cupboard is cycling on and off quite frequently and it seems to be independent of the HW or CH.
Is this likely to be some sort of frost protection circuit keeping water moving through the boiler / HWC loop?
Ta.
I've noticed that on occasion our CH will come on in the middle of the night, when freezing outside, when it should definitely not be doing so. Our boiler is also out in the garage.
In fact last winter the frost 'stat failed, and the heating stayed on solid for a couple of days. I was away working, and wifey only decided to e-mail me about it when the house got to a tropical 28c. She thought it was great......
But then she doesn't pay the gas bills.
So what's the standard programme that boilers use for frost protection?
Presumably it just runs the boiler and pump for a fixed amount of time, stops for a fixed amount of time and then repeats the cycle until the thermostat switches off.
This time of year it could be repeating this cycle for weeks - no?
There must be a cost in terms of gas usage and pump wear to this set up?
In my last house the boiler was in the kitchen so there was no frost protection cycle.
I may have to think about relocating this boiler or fixing a radiator in the garage.
Presumably it just runs the boiler and pump for a fixed amount of time, stops for a fixed amount of time and then repeats the cycle until the thermostat switches off.
This time of year it could be repeating this cycle for weeks - no?
There must be a cost in terms of gas usage and pump wear to this set up?
In my last house the boiler was in the kitchen so there was no frost protection cycle.
I may have to think about relocating this boiler or fixing a radiator in the garage.
rfisher said:
Presumably it just runs the boiler and pump for a fixed amount of time, stops for a fixed amount of time and then repeats the cycle until the thermostat switches off.
I think that is just about it. Running the boiler must generate local heat to stop pipes freezing. I guess the 'stat warms up for a while, then when it cools again it just fires up the heater. Unless your heating is turned totally off I don't think it will run much more than normal, in freezing conditions. Ours is set to keep the house at 19c from 11pm to 5am, then 22c the rest of the day,, so in coldest winter it will pop on and off fairly regularly anyway.russ_a said:
Our combi is in the loft and will keep anyone awake in the bedroom below!
Hopefully, boarding the loft with reduce the noise a little. Seemed a good idea at the time to get it moved from the kitchen to the loft.
We get horrendous noises from our system too, even though it is in the garage, but the pipes, pump and water tank are on the landing. It sounds like a plane zooming around, it knocks, clanks, ticks, rattle etc. Next year we will probably convert to a combie boiler anyway.Hopefully, boarding the loft with reduce the noise a little. Seemed a good idea at the time to get it moved from the kitchen to the loft.
Frost protection on old systems is very crude, all it will do is bring the heating on until the temperature is out of the "danger zone", so this could keep the heating on until the morning!
Might be worth moving the frost stat closer to the pipework, so it will pick up some heat emmitting from the pipework and knock the heating off.
Modern boilers monitor the system water temperature and will knock off when the temperature has been raised.
Might be worth moving the frost stat closer to the pipework, so it will pick up some heat emmitting from the pipework and knock the heating off.
Modern boilers monitor the system water temperature and will knock off when the temperature has been raised.
t installation.Ricky_M said:
Frost protection on old systems is very crude, all it will do is bring the heating on until the temperature is out of the "danger zone", so this could keep the heating on until the morning!
Might be worth moving the frost stat closer to the pipework, so it will pick up some heat emmitting from the pipework and knock the heating off.
Modern boilers monitor the system water temperature and will knock off when the temperature has been raised.
The op said that there was a air stat and a pipe stat,they should act as an "and gate". If the room temp is <3 deg and the pipe temp <60 deg then run boiler and pump,if ether condition is not true then the heating is under normal control.Might be worth moving the frost stat closer to the pipework, so it will pick up some heat emmitting from the pipework and knock the heating off.
Modern boilers monitor the system water temperature and will knock off when the temperature has been raised.
I would suggest that 60 is too high btw.
I've sorted it by dropping the hot water temperature sensor to 45oC from 55oC.
I think it was actually the HW circuit that was on all the time as the system couldn't get the water up to that temp and the return pipe sensor was shutting down the boiler to prevent overheating.
I've only recently moved into this house so it's probably been doing this for years
May explain why there's a disconnected old burnt out pump under the HWC.
I think it was actually the HW circuit that was on all the time as the system couldn't get the water up to that temp and the return pipe sensor was shutting down the boiler to prevent overheating.
I've only recently moved into this house so it's probably been doing this for years
May explain why there's a disconnected old burnt out pump under the HWC.
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