When it comes to heating your home year round with a low energy cost, eco-friendly alternative, a Geothermal system is the answer. Geothermal heat pumps are also known as Ground Source Heat Pumps (GSHPs). GSHPs operate by collecting heat from the Earth, the largest solar collector in the world. The heat retrieved from the constantly stable ground source or geothermal water source temperature is then transferred into your home. Geothermal applications work because although the air temperature in the winter could drop in some places to 30 below zero, ground and water source temperatures will remain in a constant 40 to 70 degrees, depending on your location, providing a heat source.
Many people think that they are automatically doing the most efficient thing by paying extra for a multi stage or speed compressor. This upgrade might cost $700.00 or much more depending on the brand of equipment. It is true that the efficiency of a heat pump is higher while it is running on the slower speed. There are drawbacks that not too many people like to talk about though. 2 speed, or variable speed compressors are more complicated than the standard single speed compressor that has been used in the trade for the last 90 plus years.
From my personal experience and also from talking to heat pump engineers after hours when they are not on the clock, I have learned that multi speed compressors are more sensitive to voltage surges, wiring issues, and premature failure, etc. I never recommend that they be used in restaurants with multiple heat pumps conditioning the same space where there are heavy guest loads and at peak the unit will be running close to 100% and or the units are off when there is no load because the multiple units in the building could act in a way as a unintentional 2 speed compressor as one unit might be going at 100% when another in the building is off. That keeps things simple and reliable.
That also goes for office buildings where the load on each unit can be staggered with a multi stage thermostat, and or by using different temperature set points. Some manufacturers don't even send their 2 speed units out to be rated at the lower speed because they think it is not an honest way to rate then as the time they are running at reduced load is not enough to effect the bill at the end of the month in a financial way. They also think that when people are using the super high efficiency numbers during their research comparing different brands, that those numbers won't accurately reflect the efficiency performance in the real world and might cause them to spend more money to get a payback that will take years.
There are time when multi speed compressors make sense. Sometimes a home in the mountains can use one as they might have a large heating load in the winter but hardly any cooling load in the summer and a lower speed might help keep the humidity down when they do need some cooling.
We can make your geothermal heat pump in any compressor configuration that you want. They go out in about one in 20 shipments from us. Ask us before you spend extra money to see if this option will be in the best interest for you. This advise doesn't apply to mini splits. They are a whole different world.