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Heat Pump Discharge Air

John shane

Registered User
Joined
Feb 13, 2020
Messages
12
Location
California
Hi Everyone,

So we are redesigning an existing residential apt and we are providing a heat pump water heater because the house doesn't have gas and more so we can't pass t24 with an electric water heater.

We all know that environmental air exhausts termination need to be 3ft away from openings into the building. Now, is a heat pump's discharge air considered as an environmental exhaust and would need to follow that termination clearance too? As far as I know some installations even install discharge of a heat pump with 2 way ducts so that in summer you can use a damper and direct the cold air for additional cooling to the house.

The only place that we could duct it is to a wall is in between 2 windows, the wall length is just 3 feet so we won't be able to comply with the requirement.

Honestly I just think that I can do it as it is clean air that is being discharged to the environment. Wdy guys think
 
Not my area

Interesting did not know they made a

heat pump water heater

I vote for three feet required


[MP] MECHANICAL EXHAUST SYSTEM. A system for removing air from a room or space by mechanical means
 
What does the manufactures installation instructions say? Do they require the air to discharge to the outside?
You are not removing products of combustion or environmental air
 
Is the heat pump a split system? Most of the heat pump water heaters I've seen have the heat pump built on top of the water heater and just recirculate air. I think they require a certain minimum volume of the room they are in to minimize short-cycling of the air.
 
Is the heat pump a split system? Most of the heat pump water heaters I've seen have the heat pump built on top of the water heater and just recirculate air. I think they require a certain minimum volume of the room they are in to minimize short-cycling of the air.
That's all that I have seen.

The one side note that I have with these heat pump water heaters is that they pump out a ton of cool air. For that reason, they are best installed in a dedicated mechanical room or garage. If installed in the home, they will scavenge the heat from the home, and pump out the cool air. If in a laundry room or similar, it can make the area feel like it has quite a draft.
 
First thing to look at is the manufacturers Installation Clearances. Also how much Clearance is required for Maintenance and Are there Zoning restrictions on placement?
 
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