Condensing boiler in mechanical room outside building envelope
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I have been asked to insulate a new home on the coast of Maine. The home is super-insulated and will have 12″ thick walls, insulated slab with great solar exposure.
the mechanical room, is a 10’x10′ stucture that is attached to the building but has its own roof and only 2×6 walls. It has not been air sealed during construction but the plan calls for cellulose in the walls and ceiling.
The plan is to insulate the mech. room and install elec, heat to keep it warm and then completely seal it off from the thermal enclosure of the home. I have concerns about this. What happens when you lose power? the house will not freeze for weeks, but the mech. room will in days.
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Replies
Bo,
It's obviously rare for the power to be off for a week, but it happens.
Whether or not to plan for such a rare event is up to the owner.
Certainly, if there were ever a major ice storm, and the power was out for a week, there would be enough time to drain the pipes and drain the boiler. Not a fun job, though, especially in the cold.
If the owner wants a backup heat source, you can always install an Empire propane space heater with a through-the-wall vent. They make models that don't require electricity.
Great stuff, Martin.
I had not thought of a back-up heater that needs no electric power. My main concern was a mech. room that is so cut off from the home. It just never seems right to disconnect any part of the home, basement, crawl or boiler room. But the more research I do the less I am concerned in this particular instance. Draining the boiler was another great point- Thanks!!!!