Heat Pump Size: Making an Impact on Cooling and Humidity

If you’re having a heat pump installed, you should know that proper equipment sizing is crucial in maintaining home comfort, especially when it comes to summertime cooling and humidity control. For that reason, be sure that your contractor is using a detailed heating and cooling load calculation to determine your needs, rather than using a “bigger is better” philosophy or judging those needs according to the size of the equipment you’re replacing.

When it’s in cooling mode, a properly sized heat pump works to cool and dehumidify your home in much the same way as a traditional central air conditioning system – by using refrigerant to absorb heat from inside and carrying it outdoors, where it’s dispersed into the air by the condenser coil. As the indoor air is cooled, some of the moisture it carries condenses on the evaporator coil and drains away, reducing humidity. The chief difference between the two is that, during cold weather, a heat pump reverses that cycle, bringing outside heat into the home to warm the indoor air.

Like an air conditioner, a heat pump must be sized properly to maintain optimal performance and efficiency. If it’s too small to handle to cool your home, it will run much more than should be necessary to keep up with the summer heat, raising your energy costs. If it’s too large, a much more common problem, run cycles will be shorter than they should be. Starting and stopping repeatedly uses more energy than a longer run cycle, reducing energy efficiency and providing uneven cooling. And since your system only removes moisture from the air when it’s running, short cycles mean less efficient humidity control. So make sure your equipment is chosen according to precise load calculations, rather than a casual estimate.

For more information on how heat pump sizing affects the efficiency of cooling and dehumidifying your home, please contact is at Sobieski Services. Our goal is to help educate our customers in Delaware, Pennsylvania, Maryland and New Jersey about energy and home comfort issues (specific to HVAC & plumbing systems).

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