HVAC contractors in the United States

Two demand peaks, not one

Nearly every other trade on this site has one busy season. Heating and cooling has two, and they sit at opposite ends of the year. The first sustained heat of the summer and the first hard freeze of the winter each produce a wave of no-heat and no-cooling calls inside about seventy-two hours, and the same technicians answer both.

That shape matters when you are choosing a contractor. Work booked inside a peak is emergency work, priced and scheduled as emergency work, and the diagnosis happens under time pressure. Equipment replacement decided in a heat wave is decided in the worst conditions for deciding it. Where a system is old enough that the question is coming anyway, the cheap month to ask it is a shoulder month, when the same company has an empty calendar.

The mix between the two peaks is regional. In a metro where cooling dominates the energy bill, the summer wave is the larger one and a failed compressor is the emergency; where heating dominates, the winter wave is larger and a failed heat exchanger is. The counts on this page do not distinguish the two, because a contractor record does not say which half of the year it earns its living in.

Source: U.S. Energy Information Administration, Residential Energy Consumption Survey

EPA Section 608, the credential no state board issues

Anyone who opens a sealed refrigerant circuit to maintain, service, repair or dispose of air conditioning and refrigeration equipment must hold an EPA Section 608 technician certification, issued through an EPA-approved certifying program under the Clean Air Act. It comes in four types: Type I for small appliances, Type II for high-pressure equipment, which covers ordinary split-system air conditioning and heat pumps, Type III for low-pressure equipment, and Universal for all three.

Two things follow that surprise people. The certification belongs to the person, not to the company, and it is federal, so it is the same credential in every state and no state board issues it, renews it, or publishes it. This site does not publish Section 608 status on any record, because there is no national register of certificate holders to publish it from. The EPA's own page is the place to read what the certification covers, and the technician who arrives is the person to ask for the card.

The certification exists because refrigerants are regulated substances rather than because they are difficult to handle. Venting them is prohibited, recovery equipment is required, and sales of certain refrigerants are restricted to certified buyers.

Source: U.S. Environmental Protection Agency, Section 608 technician certification

What a load calculation actually is

A load calculation is a room-by-room computation of how much heat a house gains in summer and loses in winter, built from its insulation levels, window area and orientation, air leakage, ceiling heights and the design temperatures for the local climate. It produces the capacity the equipment has to deliver, and it is the only defensible basis for choosing a system size.

The common alternative is to read the nameplate on the old unit and order the same tonnage. That carries forward whatever the previous installer guessed, and it ignores every change made to the house since: new windows, added insulation, a finished attic, a sealed crawl space. Oversized cooling equipment cools the air before it has removed the humidity, then shuts off, which is why an oversized system can leave a house cold and clammy at the same time.

Asking for the calculation is a reasonable request and a fair test of a quote. A contractor who has done one can show you the inputs.

Source: U.S. Department of Energy, sizing a new heating and cooling system

When replacement starts to beat repair

Three things move the answer away from repair. The first is age against the equipment's service life, because a repair on a system near the end of it buys time on a machine that will ask again. The second is the size of the repair against the price of replacement; a compressor or a heat exchanger is a large fraction of a new system, a capacitor or a contactor is not. The third is the refrigerant.

Systems charged with R-22 sit on the far side of a production and import phase-out completed under the Clean Air Act, so the refrigerant that services them now comes from recovered and reclaimed stock. That does not make a working R-22 system illegal or unsafe, and it does not require anyone to replace one. It does mean that a large leak repair on such a system is a different economic proposition from the same repair on current equipment, and a quote that does not mention which refrigerant your system uses has skipped the question.

Source: U.S. Environmental Protection Agency, phase-out of ozone-depleting substances

HVAC questions answered on this site

• AC not cooling: repair or replace?
• Heat pump or a new furnace: which replacement makes sense?
• My air conditioner uses R-22. What are my options?
• Do I need a permit to replace my furnace?