Geothermal heat pumps are one of the most versatile heating and cooling technologies available, but there are two applications where they don’t shine: producing water hot enough for hot-water baseboards and completely heating domestic hot water. Sure they can preheat water for these purposes, but using a geothermal heat pump as the sole provider of hot water baseboard heat or domestic hot water isn’t feasible. Until now, that is.
To combat this limitation, we’ve designed a heat pump that takes preheated liquid and further boosts its temperature as high as 160°F (71°C). We’ve named it the high-temperature water-to-water heat pump. Let’s look at how it works and when it will be most useful.
What is a High-Temperature Water to Water Geothermal Heat Pump?
Unlike our standard water-to-water heat pump (which uses a ground loop or water well), the high-temperature water-to-water heat pump uses a preheated incoming liquid as its energy supply source. The incoming liquid must have a temperature of between 50°F (10°C) and 122°F (50°C). Typically this energy supply source is a buffer tank connected to the indoor side of a geothermal heat pump, or it could be the cooling loop from an industrial process.
The high-temperature water-to-water heat pump takes the preheated liquid and uses it to heat water as high as 160°F (71°C). It accomplishes this by using R134a refrigerant, which has a higher temperature range than traditional R410a.
Uses for High-Temperature Water to Water Heat Pump
The most common use for the high-temperature water-to-water is to heat domestic hot water in a commercial building that already uses a geothermal heat pump for space heating and cooling. You can also use this heat pump for hydronic heating in situations where a typical geothermal heat pump cannot provide hot enough water for sufficient heating. Situations like this include hot water baseboards designed for hot water from a boiler. Just remember you need to have a preheated source.
Concept and Design of the High-Temperature Water to Water Heat Pump
This project is the answer to the age-old question of how a geothermal heat pump could provide 100% of the demand for hot water in a commercial building. Our product engineer Dan Rheault designed it. Watch as he takes an in-depth look inside the machine:
Depending on the source temperature, the high-temperature water-to-water heat pump will have a coefficient of performance (COP) of between 2.5 and 6.5. This heat pump is available from 2 to 7.5 nominal tons. For larger applications, multiple units can be used in parallel, making it ideal for large commercial applications.
Learn how geothermal heat pumps can save you money on your commercial building operations by downloading our free Ebook: 6 Ways Geothermal Heating Will Benefit Your Commercial Installation.