The protocol for planning a building’s HVAC equipment used to be quite simple, but also resulted in quite oversized systems. The HVAC industry now recognizes the myriad of factors that come into play when determining the heating or cooling load of today’s energy-efficient homes. Blue Valley Energy in Longmont uses the industry’s most detailed protocols to accurately calculate your home’s heating load so you don’t waste money on a heating system that is more than you need.
Heating Load Calculation
- Design Heating Load= how much heat is needed for indoor and outdoor temperatures at winter design conditions. The ACCA Manual J, or Air Conditioning Contractors of America Residential Load Calculation Manual, lists outdoor and indoor winter temperatures of each major U.S. city to be used for calculation protocols.
- Extreme Load= the heating need when temperatures are coldest for your region. However, furnaces should not be sized to meet the demand of extreme load for several reasons. First, the design load calculation provides a 15-20% buffer, a moderately well-insulated house creates some lag-time before effects of extreme outdoor temperature are felt inside, and because these temperatures only occur for a small percentage of time.
- Part Load= the heating need for the majority of the day before design temperature is reached. Since most homes today are more airtight and insulated to be energy efficient, the full capacity of even the smallest furnaces of 30-40,000 BTU/hr is hardly ever reached.
A knowledgeable HVAC technician will take into account all three of the aforementioned heating loads before making a capacity recommendation for a new furnace. Depending on how airtight and insulated your house is, another heating system such as mini-split heat pumps may make more sense for your building’s needs. Whether you’re building a new home or renovating an older one, the team at Blue Valley Energy in Longmont can conduct a heating load analysis, suggest the most effective heating system and expertly install it!