My house has a gas-fired boiler and hot-water radiators. I've noticed a strange problem since moving in a few months ago.
If the weather is moderately cold (in the 30F – 40F range), my house feels chilly.
But if the temperature gets very, very low (say between 10F – 20F), bizarrely, the furnace seems to do a better job. My whole house feels toasty; so much so that I'll often be caught off guard when I leave the house.
What could cause this?
Best Answer
Just a guess, but the colder it gets the longer the boiler cycles and the hotter the delivery water temperature gets so therefore the radiators get hotter before the thermostat shuts the boiler off.
In moderate temperatures, the thermostat shuts the boiler off before it gets very warm and so your radiators are barely above room temperature.
Check to see if your boiler has any kind of temperature control on the delivery water going out into the system. You may be able to adjust that for better performance in moderate weather.
Good luck with your project!