When a heat pump activates auxiliary heat, it means the primary system cannot meet the heating demand efficiently due to cold outdoor temperatures, a defrost cycle, or a rapid thermostat adjustment. This backup heating, often electric resistance or gas, supplements the heat pump to maintain comfort. Occasional activation is normal, but frequent use may indicate system issues or improper sizing.
In air conditioning, a ‘ton’ is a measure of cooling capacity rather than weight. It refers to the amount of heat an AC unit can remove from a space, specifically equivalent to the heat required to melt one ton of ice in 24 hours.
A thermostat override is a temporary adjustment that bypasses the programmed schedule, allowing the user to manually set a desired temperature for a limited time until the next scheduled period or manual reset.
High superheat refers to a condition in refrigeration and HVAC systems where the refrigerant gas is significantly warmer than its saturation temperature. This typically indicates a lack of refrigerant or a restriction in the system’s flow.
The ‘Hold’ feature on an air conditioner or thermostat locks the current temperature setting, overriding any programmed schedule. It is used to maintain a consistent temperature until manually changed or canceled.
Airwave is a feature on Nest thermostats that improves energy efficiency by running the fan after the air conditioner compressor shuts off, circulating residual cool air from the coils into the home.
The ‘Auto’ setting on an air conditioning system allows the unit to automatically manage fan speed and temperature to maintain a set point. It reduces the need for manual adjustments by utilizing sensors to regulate the climate.
In HVAC, a ton measures cooling capacity equal to 12,000 BTU per hour. It originates from the heat required to melt one ton of ice in 24 hours. This standard helps size air conditioning systems for residential and commercial buildings.
Stage 1 on a thermostat refers to the first stage of heating or cooling operation, typically engaging the primary heat source or compressor at a lower capacity. It is part of a multi-stage system designed to improve energy efficiency and comfort by matching output to demand.
On Honeywell thermostats, CIRC (short for Circulate) is a fan mode that runs the fan periodically even when the heating or cooling system is off, helping to circulate air and maintain more even temperatures throughout the home without continuously running the fan.