If you’ve ever installed a ductless mini-split system before, you already know that mini-split sizing can be one of the most complicated but critical aspects of the job. Specifically, knowing how to size a mini-split unit requires knowledge of a building’s electrical system, room sizes, and building envelope. With this information, you can confidently recommend the right mini-split sizing and zoning to meet the client’s needs.
Explore answers to some of the most frequently asked questions about sizing a mini-split below to better inform your own work as a heating and cooling professional.
A: Single- and multi-zone mini-split heat pump systems are available to suit your clients’ needs. You’ll probably find that most clients want a multi-zone system because they can control the temperature in each room of the home separately (assuming each room has its own air handler). On the other hand, a single-zone system allows for just one temperature to be set for the entire system.
Ultimately, the decision between a single- and multi-zone heat pump unit should be up to your client. As an HVAC professional you can best serve your clients by explaining the differences between these optionsandtheir inherent pros and cons.
A: Air handlers, also known as indoor units, are generally required to maintain the temperature of each room, or zone, within a building. Spaces such as hallways and half baths typically don’t require their own air handler because they will receive enough airflow by being near rooms or zones with dedicated air handlers.
When determining the number of air handlers needed in a building, you can also figure out how many condensers or outdoor units will be required. Typically, you can connect about eight air handlers (give or take based on manufacturer and design) to a single outdoor unit. If your client needs more than eight rooms to be temperature controlled, you may need to recommend multiple outdoor units.
A: Sizing amini-split systemproperly is vital to system performance and the overall comfort of the space. The larger the space being conditioned, the higher the BTU output of the air handler will need to be. However, other factors need to be taken into consideration, including:
As an HVAC professional, your best bet for getting an accurately mini-split heat pump system is to perform a load calculation.
Sizing a mini-split heat pump system for a client will take some careful consideration and calculation on your part. However, with the right information, you can ultimately recommend a mini-split system that suits your client’s needs and budget. From there, you can set your customers up for long-term comfort. And along the way, CE has all theductless mini-split equipmentyou need from the industry’s most trusted brands.