A coil is generally used to quickly remove or add heat into the surrounding medium. The two most common ones are part of the HVAC system which has an Evaporator Coil & a Compressor Coil. Coils may also be found in Certain hot water systems, like boilers, solar thermal, etc…

The Compressor’s coil is designed to take that heat that was picked up from the inside from the evaporator coil (remember hot moves to cold) and generated by the compressor to be dumped outside. The larger the compressors coil is, the more efficient the system will generally be which is one reason why the systems seem to […]

A condenser is a device or object used to turn a gas or vapor back into a liquid. While long glass tubes were used by scientists for centuries, the most common type found in a home or business is a mechanical one used on refrigerators, freezers, and Air Conditioning units.

COP or Coefficient of Performance is a ratio used to measure the heating performance of the heat pump when it reaches steady state. It is comparable to knowing what your cars MPG is on the highway while not taking into account the hills, construction zones, and in town driving.

A Duct Blaster is a piece of test equipment manufacturered by the Energy Conservatory for testing Duct Leakage. Many commonly refer to the testing of duct leakage by this name which is incorrect, but shows some good or maybe just some lucky marketting chops.

EER or Energy Efficiency Ratio is how they originally rated cooling appliances like your HVAC or window mounted unit. This rating takes the cooling capacity in Btu/h and divides it by the energy input required in watts (Btu/W-h). Unlike the , this measurment is only taken when it reaches its steady-state and is measured at 80°F indoors and 95°F outdoors.

An ERV stands for Energy Recovery Ventilator (though some like to change the word energy with “enthalpy”) is a device that is designed to exchange stale indoor air air from the outside while preconditioning it. The ERV accomplishes this by passing both streams of air through a filter which allows for the transfer of heat & mouisture between the […]

The main purpose of the Evaporator coil (which can looks like a regular radiator or even a tent) is to allow the hot incoming air to cool down quickly by passing through it (aka sensible heat). Because the temperature of the coil is so cold it also acts as a condensing surface to help remove the moist humid air […]

An exhaust only ventilation system is where one or more fans (generally bath fans) is used to exhaust air from a house (generally 24×7 though some are on timers) and make-up air is supplied “passively” (i.e. through cracks & holes in the walls, through insulation, critter dens, etc…). This type of vetilation strategy is used primarily […]

HDD or Heating Degree Day, is a unit used for estimating /modeling the energy needed to heat a building. The standard practice is to subtract the average daily temprature from 65° (a day with an average temprature of 45 would equal 20). The annual HDD combines all the days with an average temperature below 65°.