Heating and cooling in Coeur d'Alene
In Coeur d'Alene, heating is the main event. Summers bring hot afternoons, but the air is dry and the nights cool off. Winters are long and cold. A system here should be sized and chosen first for the coldest nights, then checked for how it handles a dry summer heat wave.
The weather data
NOAA has an engineering weather station at Coeur d'Alene (elevation 2,320 feet). Its figures:
- a 99% winter design temperature of 9°F;
- a 1% summer design temperature of 88°F, with a mean coincident wet-bulb temperature of only 63°F;
- about 27 hours a year at 93°F or hotter;
- no hours in an average year with the wet-bulb temperature above 73°F, and only about 28 above 67°F;
- about 44 freeze-thaw cycles in an average year.
That last pair of humidity numbers is the important one for cooling. In a humid Southern city, a large share of an air conditioner's work goes into pulling moisture out of the air. Here, almost all of it goes into lowering the temperature, which changes how the equipment should be chosen and set up.
Heat pump, furnace or both
A Coeur d'Alene home might heat with a gas furnace, a heat pump, or a heat pump with a furnace or electric backup for the coldest weather. Ask each contractor:
- how the heat pump they propose performs at 9°F, and at what outdoor temperature backup heat takes over;
- what kind of backup heat the system uses, and what it costs to run;
- how the outdoor unit will be placed and raised so snow and ice don't bury it;
- what the expected yearly operating cost is for each option, not just the installed price.
Cooling in dry air
With so few humid hours, a properly sized air conditioner or heat pump mostly removes heat, not moisture. Ask the contractor how they'll set the system's airflow for a dry climate, and whether it makes sense to size the cooling side around the heating load. For a house that only overheats on a few afternoons, ask about the comfort and cost of a smaller system against a larger one.
Efficiency rules
Idaho is in the Department of Energy's North region, where split-system central air conditioners installed on or after January 1, 2023 must be rated at least 13.4 SEER2, and split-system heat pumps at least 14.3 SEER2 and 7.5 HSPF2. Those are floors. In a heating-heavy climate, the heating rating of a heat pump deserves as much attention as its cooling rating; ask what a higher HSPF2 unit would save in your house.
Sizing and ducts
A replacement should start with a load calculation for your house: its insulation, windows, air leaks and the 9°F design temperature. Don't let the size of the old unit decide the size of the new one. Ask the contractor to inspect the ducts, especially any that run through a cold attic or crawlspace, where leaks and missing insulation waste heat all winter.
Idaho's rules for HVAC work
Since July 1, 2004, Idaho law has made it unlawful to engage in the business or work of heating, ventilation and air conditioning unless the person, or the person responsible for the firm, has passed an examination and holds a state certificate of competency; HVAC contractors must also provide a $2,000 bond. The Idaho HVAC Board sits within the Division of Occupational and Professional Licenses.
Idaho's Contractor Registration Act has made it unlawful since January 1, 2006 to work as a contractor in Idaho without registering as the act requires; a single casual, minor or inconsequential project whose total price for labor, materials and everything else is under $2,000 is exempt.
Before you sign, look the company up on DOPL's license search: a contractor registration for general work, and for heating and cooling work an HVAC certificate of competency.
Comparing quotes
Put each quote on the same terms: equipment make and model numbers, SEER2 and HSPF2 ratings, the load calculation, backup heat, duct work, thermostat and controls, removal of old equipment, the permit, start-up checks and the parts and labor warranties. A quote with only a tonnage and a price leaves too much out.