We just bought a new house (new to us, it was built in 1960 and unrenovated) and only have a few days before we leave it for November/December. We are planning to leave the heat on with the thermostat set low (50f/10c), but I'm not exactly sure what to set the thermostatic valves on the radiators to. My first thought is that I should make sure to set them all to the same temperature to ensure even heating throughout the house, however I'm not sure which setting that should be at, or even if maybe I should be setting the valves further from the thermostat to higher settings, since they will lose heat more quickly, and it doesn't help anything if it's 10c in the middle of the house and below freezing for the pipes in the exterior walls.
A few details about the house:
- Three stories though only the first and second floor are heated.
- Built in 1961, concrete construction, totally uninsulated, totally unrenovated.
- Radiant heating from a heating oil furnace.
- We only have about 700 liters of fuel to make it until the end of December when we return.
- Average temperature in the town we live in (French alps) never really dips below freezing until January.
To sum up, what should I set the thermostatic valves at to maintain an even temperature throughout the house with minimum fuel usage?