Acceptable Humidity Levels

[Joe Reefer]

HRV's are only an option to reducing heating costs by recovering some of the heat being exhausted. To elimate moisture issues you must "exchange air" simple as that.

If you are truly serious about not having any moisture issues, a make-up air system should be considered. This would include a small furnace with a stainless steel heat exchanger to draw 100% fresh air from the outside, there would also be an exhaust fan interlocked with the furnace. The cfm output of the furnace and exhaust fan should be close in performance. An HRV can then be used on this to recover some of the cost running this system when its -40.