Boat Heating - Marine Heat Pumps

Is a Heat Pump the Best Boat Heater for My Boat?

Heat pumps are extremely efficient solutions for heating homes and buildings. They are more efficient than hot water, steam or furnace systems. But, do heat pumps work well for marine applications? It turns out that air conditioners with heat pumps are even MORE efficient on boats than they are in homes and buildings in cold weather.

They're cleaner than propane boat heaters or diesel boat heaters, more environmentally friendly and not only do they use less power than electric boat heaters, they also provide air conditioning when the seasons change. Unlike boat diesel heaters, heat pumps have no flames or smoke. And, their noise level is low and consistent - no crackles or banging as they heat up! Also, most come with remote controls.

They are very similar in operation to geothermal heat pumps (aka ground source heat pumps).

How do Heat Pumps work?

Heat pumps are basically air conditioners that run in reverse. They use a refrigerant (like freon) to transfer heat from one area to another through an ongoing cycle of compression, movement and evaporation. Our how marine ac works page explains this in more detail. Heat pumps can run from 115v or 230v shore power of can be used as a 12v heater for boats when connected to an appropriately sized battery bank. See our page on battery-powered boat AC here.

Heat pumps are able to capture heat from outside and bring it inside. They do this by using the outdoor medium (air or water, in this case) to heat up the liquid that was super cooled in the evaporation process. They then use a boat heat exchanger to heat or cool the air flowing through your boat's HVAC system.

In marine applications, instead of pulling heat out of the outdoor air, marine heat pumps pull heat from the water. This process uses less energy than most other heating systems - especially for heating a boat cabin. They may require more installation work than a traditional boat heater kit would, but can work on smaller boats as well as large yachts.

Reverse Cycle Air Conditioner from Marinaire
Marinaire Heat Pump Air Conditioner Unit

Top 10 reasons to consider a marine heat pump for heating your boat:

  1. Heat pumps also can provide air conditioning as well. In fact, all marine heat pumps we've installed are also very efficient air conditioners
  2. Marine Air Conditioners with heat pumps usually provide humidity control in addition to temperature control - so your boat can be truly comfortable on colder days, not just warm
  3. Some marine heat pumps now offer variable speed compressors and fans - to make them even quieter, more efficient and longer lasting
  4. Marine heat pumps can provide efficient heat in water temperatures as low as 40 F (this continues to go lower as technology improves). While diesel heating for boats doesn't have this limitation, it's rare for most recreational boats to sail in waters under 40 degrees.
  5. You can run a DC marine heat pump from Lithium Ion batteries or other high performance batteries to make your boat heater 12v powered. We've installed systems than can heat or cool all night without any generator power
  6. Marine heat pumps are very safe. They are computer controlled and have many safeguards in place to ensure safe operation. They also don't suffer from the funny smells of some electric heaters that tend to burn off dust that collects on the resistors and they don't require flammable fuels like diesel heaters or propane heaters
  7. If your boat has an air conditioner today, it can usually be replaced with a more efficient unit that includes the ability to run as a heat pump
  8. Marine heat pump units don't burn any fuel and don't create any exhaust gases/smoke unlike propane, kerosene or diesel heating system. They are much more efficient than conventional electric boat cabin heaters
  9. Heat pumps can be configured to run on 115v or 230v to match the voltage of other appliances on your boat
  10. New marine heat pump ac units are cost effective and can typically be installed in a day or so by professionals