Hello everyone. Although a new poster I've been reading this forum for a couple years and I've heard a lot of great advice here. I am designing a new home with energy efficiency as the top priority and I am in a quandary about the heating system. Here's the specs.
1500 sf. 2 br 2 bth. R40 walls, R65 attic, 3X glazed windows. The house is in Western MT. (zone 5 I believe)
I would like to use a hydronic system in this house, but the heat loss calcs don't require much heat in the house at all with all this insulation. High mass floor radiant is too expensive, and will likely overheat the house, even if well designed based on experience. My idea is low temp (<120) radiators or fin tube with a condensing boiler. Theoretically if I oversize the units I can run lower water temps through them and thus actually make use of the extra efficiency afforded by the condensing boiler. My concern is that there will be a serious lag in warming the house with low temp water. Should the system be run like a high mass system and kept at a constant temp instead of turning down the thermostat, or will the outdoor reset be sufficient to overcome the lag. Will this even work? Plan B would be to install a basic fin tube system with an old technology boiler and just learn how to work with the thermostat. Any thoughts would be appreciated. Thanks
1500 sf. 2 br 2 bth. R40 walls, R65 attic, 3X glazed windows. The house is in Western MT. (zone 5 I believe)
I would like to use a hydronic system in this house, but the heat loss calcs don't require much heat in the house at all with all this insulation. High mass floor radiant is too expensive, and will likely overheat the house, even if well designed based on experience. My idea is low temp (<120) radiators or fin tube with a condensing boiler. Theoretically if I oversize the units I can run lower water temps through them and thus actually make use of the extra efficiency afforded by the condensing boiler. My concern is that there will be a serious lag in warming the house with low temp water. Should the system be run like a high mass system and kept at a constant temp instead of turning down the thermostat, or will the outdoor reset be sufficient to overcome the lag. Will this even work? Plan B would be to install a basic fin tube system with an old technology boiler and just learn how to work with the thermostat. Any thoughts would be appreciated. Thanks