Residential Heat Pump Water Heater

[XR250]

How are these things efficient if they are inside your house.? Ok, free A/C in the Summer. But in the winter, they are just transferring the load to the HVAC system. Maybe they make sense if they are in an un-heated garage?

 

[MintJulep]

In a warm space the heat pump needs to do less work, so by itself it's more efficient.


The ones here in Japan have the evaporator outside.

 

[XR250]

I get it if the Evap is outside. But if it is inside, like most, the cost of it doing less work in the warm space is born by the heating and air system.

 

[LittleInch]

Do you mean stand alone ac units?

An example would be good to understand.

And very little is free......

 

[XR250]

IDK if you are referring to me or MintJulep?

This what I am referring to...

 

[HVAC-Novice]

How are these things efficient if they are inside your house.? Ok, free A/C in the Summer. But in the winter, they are just transferring the load to the HVAC system. Maybe they make sense if they are in an un-heated garage?

Maybe detail what exact product and in what application, setup and climate you are talking about. You can make a technology efficient, or inefficient depending on how you use it.

 

[LittleInch]

IDK if you are referring to me or MintJulep?

This what I am referring to...
View attachment 3459

I did mean you and thanks for confirming what I thought you meant.

"How are these things efficient if they are inside your house.?" They aren't. If you place them in the middle of a home where the exhaust fan blows freezing cold air into your heated space.

I kind of get what you mean by free a/c in that if you heat your water by electric then yes, this is getting cold air for the same or less heat input.

Like any heat pump system, you need to be extracting your heat from the ambient air outside your house for it to make sense in the winter. of course to make use of the cold air in the summer you need it inside your house, but then it won't run as much as the water is warmer and you tend to use less hot water.