Oxygen Content?

Folsom49er

My 89-year-old father has breathing problems, so I was concerned when he said he was turning off the exterior unit on his heat-pump system so his home would stay warmer during this intense cold spell. His relatively small, all-brick home is sealed up pretty tight (in WV). Should he be concerned that the oxygen content will be dropping a lot if the exterior unit isn't running?

M Downey_2

Clearification

If you mean the unit containing the compressor outside, no it shouldn't have any effect on oxygen content. However, if he doesn't have a form of back-up heat, he may become extremely uncomfortable, depending on how cold it is. But if you mean an ERV or HRV there could be a drop in oxygen content.  

BillW

Oxygen

The outdoor unit of a heatpump has nothing to do with fresh air.  It rejects heat(summer) or absorbs it (winter) as a stage of heating.  The inside unit circulates the air around, and probably has nothing to do with oxygen content either, unless it has some sort of outside air feature.  Energy or heat recovery ventilators bring in and exhaust equal amounts of air, and tend to dilute and exhaust pollutants, and bring in fesh outside air.  They are about 80% efficient, and typically are connected to your ductwork, and they run 24/7 on low speed, and can be set to ahigher speed by a manual switch, a dehumidistat or by a program on certain thermostats.

Several versions of energy/heat recovery units are available, some even have advanced filtration and ultraviolet lights for killing some pathogens.  Besidesopening a window, they are your best alternative.  I hope this was useful.

Tom Blackwell_2

Explain

The source of heat has nothing to do with oxygen content, unless there is open combustion taking place inside the home. The only way that o2 levels would drop would be for the house to be airtight, with absolutely no infiltration. Then the problem would be an increase in co2 levels long before a noticeable drop in oxygen level could be measured. That being said, there is an alarming trend amoung some advertizers, claiming that heating systems other than theirs remove oxygen from the air. This is absolute bs, in that the only mechanism available for o2 removal is corrosion-if this were true, then the aforementioned heating system would be reduced to nothing in a very short period. By turnin off the outdoor unit of the heat pump, the system would be relying on straight resistance heat, at a cost of at least twice as much as using the heat pump.