SANCO2's New Cold Climate Heat Pump Water Heater

Small Planet Supply | SANCO2 | Iced Unit

SANCO2 heat pump water heaters make for a super-efficient domestic hot water system (so great in fact, that they are a key component of the WaterDrop System, learn more here). These heat pumps work in a wide range of climates and are very efficient down to -27*f. Being used in such cold temperatures brings a common issue however, and that is the issue of ice. Read on to learn more about what’s happening to these units in super cold climates, and what ECO2 Systems has done to remedy the problem.

What Happens to Heat Pumps in Cold Weather

Small Planet Supply | SANCO2 |Interior View Cutaway

When a heat pump is operating to move ambient heat from the outside air to another source inside, the coils of the system get very cold. The process also draws moisture from the air, and this condenses on the outside of the coils. To protect the components from a buildup of water, a drain pan is incorporated into the unit, thus allowing excess moisture to drain out as it pools up. This solves the problem of the moisture build up, but what happens when water gets cold? It freezes.

When water freezes on the heat pump’s coils, it reduces the efficiency of the system. To alleviate the problem, SANCO2 heat pumps have a defrost cycle that will run automatically to melt the ice and free up the coils. The drip pan catches this water to remove it from the unit just like any other condensation. The issue arises that in very cold climates, the units will frequently see below freezing temperatures. This collected condensation will freeze in the drain pan, clogging the drain and preventing the pan from emptying.

The Solution

To fix this issue and to better serve the cold climate regions, SANCO2 has developed their cold climate heat pump. This version incorporates a heater in the drain pan that is able to keep any condensate from freezing and blocking things up. By running an electric resistance coil incorporated into the drain pan, any ice forming gets melted, allowing the drain pain to perform its function of draining water.

Small Planet Supply | SANCO2 | Drain Pan Heater

The heating coil is designed specifically to loop into the bottom of the drain pan. Unfortunately, because of the complexity of routing and not being a straight and easy to work with coil, it cannot be supplied for installation after the fact. The coil itself is only 172w, just enough to melt any ice, so the performance hit on the entire system as fairly minimal.

The coil has an automatic function and will only turn on when the ambient temperature is at or below 34*f/1*c. Once temperatures go back above this set point, the heating coil turns off. Since the coil only runs when it needs to, the performance hit only comes in those extreme temperature conditions, meaning the overall system is still highly efficient.

The Cold Climate SANCO2 unit is otherwise the same highly efficient CO2 refrigerant heat pump as the newest Gen4 design. This means you get all of these same benefits:

  • COP of up to 5 in ideal conditions is attainable by these units.

  • Water output temperature of 150*f during normal operation, dropping to 145*f below 67*f ambient.

  • Low amps draw for higher COP and lower kW draw.

  • Double wall refrigerant to water heat exchanger, and seacoast coated evaporator coil.

To place an order for one of these new cold climate units, or any other SANCO2 products, give us a call at 360-866-8779.

If you have questions about whether the SANCO2 heat pump water heater is right for you, you can schedule a consultation with one of our Small Planet Supply team members by clicking on the button below or check out the SANCO2 page of our website.