Many homeowners are turning to ductless mini-split heat pump systems as an efficient way to heat and cool their homes. Mini-splits provide high-performing, zoned temperature control without the need for centralized ductwork. However, some customers may be in for a surprise when they see their monthly electric bill after installing a mini-split system. Here are a few key reasons why your electric usage – and subsequently your bill – could potentially rise:
More Hours of Operation – With a convenient, individual thermostat for each indoor unit, homeowners tend to use their mini-split system more frequently than a traditional central AC or furnace. People may set the temperature a few degrees cooler in the summer or warmer in the winter and leave it running longer since it’s so energy efficient. This increased “on” time results in higher overall kilowatt-hour usage.
Supplementary Heating/Cooling – Mini-splits allow you to heat and cool targeted areas instead of the whole house. Individuals may be more liberal about adjusting the temperature in different rooms as needed. For example, keeping the master bedroom cooler at night while still heating other parts of the home. The extra conditioning adds to your cumulative electrical consumption.
All-Electric Operation – Mini-split heat pumps replace fuel-burning furnaces, boilers or baseboard heaters that use natural gas, oil or propane as the primary heat source. These fossil fuels are inherently cheaper to operate than electric resistance heating. So homes relying solely on mini-split heat pumps for winter temperatures require more expensive electricity versus a mixed system.
Sizing & Zoning Choices – It’s common for customers to install an HVAC system larger than strictly necessary or zone off more areas than truly warranted. Oversized mini-splits will heat/cool rooms very quickly but run much longer cycling on and off, increasing electricity use versus right-sized equipment.
Auxiliary Devices – Many new homeowners add humidifiers, ventilators or additional filters to their ductless mini-splits, all of which consume modest amounts of extra power constantly. Over time, these small parasitic loads contribute to higher utility costs.
Despite the potential, mini-split heat pumps remain very energy efficient choices that can reduce HVAC expenses in the long run compared to older systems. By understanding normal usage behaviors and properly sizing/zoning installations, homeowners can minimize unexpected increases to their electric bills after a ductless mini-split installation. Call us to discuss options to optimize comfort and efficiency from a new ductless mini-split system.
Here are some tips to minimize increased electric usage after installing a ductless mini-split system:
- Size the system properly for your home. Oversizing can lead to longer run times. Evolved can help with this.
- Zone rooms based on when and how they are used. Combine frequently used rooms onto one indoor head.
- Apply proper insulation and air sealing before installing to reduce overall heating/cooling needs.
- Use economical fan settings when possible instead of always running on high speed cooling/heating.
- Set accurate temperature setpoints. Too cold/hot and the system will have to work harder.
- Close vents/doors in rooms not in use to better direct conditioned air where needed.
- Consider a multi-head mini-split to better balance heating/cooling across the home.
- Have a technician perform regular maintenance to ensure optimal efficiency.
- Use timer, thermostat or app-based controls to limit run times when not home.
- Consider adding supplemental solar panels or a home battery to offset increased electric costs.
- Educate all household members on energy efficient usage habits for the new system.