We just bought a house that has radiant heat in a 600sf kitchen/living room area in Dover, NH. There’s an older Lux thermostat installed on one wall (see pic). From what we understand, the radiant was installed 12-14 years ago, along with a gas stove in the same room. We’ve been having a lot of trouble stabilizing the temp in this space. We use a separate, interior thermometer to gauge the temp as we do not trust what the old thermostat says. While it has certainly been a cold winter (it’s 3 degrees as I type this), the temp in this room seems to drop up to 10 degrees overnight – even though we do not turn it down when we go to bed. For example, when we went to bed at 10 last night, the temp was 72, when we came down this morning, the temp was 61. We keep the room closed off from the rest of the house by closing two interior doors, which we hope preserves heat. This room also has French doors and a back door that could definitely use some new weather stripping. We’re trying to figure out if this swing in temp is normal, or if we should have someone come over and look at the system? We’ve been supplementing in the mornings with the gas stove, but that’s not cheap, and doesn’t seem very efficient! Thanks for any insight!