someone enlighten me please

 

With a single stage heatpump you have one condenser, one compressor. Multistage can have multiple condensers and/or compressors. Simple as that.

 

so does that mean a heat pump with one condensor and compressor and a aux heat strip is a single stage unit?

I read somewhere that if my unit had emergency heat that it was a multistage. but a flyer I pick up at Lowes listing all their thermostats shows listing for single and multistage plus a separate listing for heat pump with or without aux heat..

the thermostats that say heat pump does not say they work with the single or multistage unit just heat pump with aux heat

 

v b chil-n

This may be difficult to tell unless you know the manufacturer/model and or listening to the condenser's compressor. Most multistage HP condensers have a single compressor that has a high and low stage. Trane and American Std's top of the line actually has two compressors within the condenser. All of the multistage HP units must have a var speed blower to operate correctly.

so does that mean a heat pump with one condensor and compressor and a aux heat strip is a single stage unit?

Not necessarily.

So these multistage heat pumps have 3 stages of heating (low,high, and includes heat strip aux heat) and two stages of cooling. These multistage HP units must have the appropriate thermostat for best operation.