Jackson/Reynolds: what NOAA publishes
NOAA's engineering weather data lists a station named Jackson/Reynolds, at an elevation of 1,001 feet. Its heating-side value is a 99% winter design temperature of 2°F. On the cooling side, NOAA gives that station a 1% summer design temperature of 88°F, paired with a mean coincident wet-bulb temperature of 73°F. NOAA also counts, in an average year at Jackson/Reynolds, about 261 hours when the wet-bulb temperature is above 73°F and about 980 hours above 67°F.
Drinking water, as a local fact
The City of Jackson's 2024 water quality report says the city's water comes from 16 groundwater wells, each one more than 400 feet deep.
Describe the trouble in your own words
An estimator spends an hour or so in your house; you spend every day there. For a few weeks before anyone visits, write down what the house actually does, and give the same page to each company that bids:
- The room or floor that feels wrong, and at what time of day.
- Whether the complaint is about heat, cooling, stuffy air, dry air, noise or a smell.
- How the thermostat is set during the day and overnight.
- Anything changed since the equipment went in: a finished lower level, an addition, new windows, a room you closed off.
- The brand, model and serial number from the labels on the furnace, the air handler and the outdoor unit.
- Recent gas and electric bills, if they are easy to pull from your accounts.
When every bid answers the same page, you can see which contractor listened.
Sizing: ask how they got the number
Each bidder will propose a capacity. Ask how they arrived at it:
- Will you run a room-by-room heat loss and heat gain calculation, such as a Manual J, and will I receive the report?
- Which outdoor design conditions did you enter, and from what source?
- Were insulation levels, window areas and air leakage measured or estimated?
- Why is the size you propose larger than, smaller than or the same as the unit coming out?
- If I sealed and insulated the attic first, would the answer change?
A contractor who matches the old nameplate without a calculation may still land on a sensible size. Ask them to explain how they know.
Moisture in the cooling months
Comfort in warm weather is partly about the water a system takes out of the air. Moisture condenses on the cold indoor coil and leaves through the condensate drain, and that only happens while the coil stays cold. Questions for each bidder:
- How does the quoted equipment handle moisture removal, according to its maker's published data?
- Is a two-stage or variable-speed option on the table, and what would it change in this house?
- Can the thermostat display indoor humidity or run a dehumidify setting?
- Where will the condensate drain run, and is there a float switch to shut the system down if it backs up?
- Would a separate dehumidifier help in one part of the house, and where would it drain?
Furnace, heat pump or a mix
Ask for a separate price on each heating arrangement a contractor is willing to install, so you can weigh them side by side:
- Gas furnace with central air. Ask for the furnace's AFUE rating, the type of blower motor, and whether the burner runs in one stage, two stages or modulates.
- Heat pump with backup heat. Ask what heating capacity the maker publishes at low outdoor temperatures, what form the backup takes, and what tells it to switch on.
- Dual fuel. Ask at what outdoor temperature heating passes from the heat pump to the furnace, who sets that point, and whether you can adjust it later.
For each arrangement, ask for an estimate of yearly operating cost worked out on your own utility rates, with the arithmetic written down.
Air delivery: ducts, returns and registers
Equipment can move only as much air as the ducts allow. Ask each bidder to look at the runs they can reach and put what they find in writing:
- a static pressure reading on the current system;
- the condition of joints, flexible runs and insulation on ducts in unheated spaces;
- whether the return side can supply enough air for the proposed blower;
- a separate line for sealing and repair, so the equipment and the ductwork are priced apart.
Ask, too, whether any room needs a new return path or a larger register, and what that adds.
Exhaust, combustion air and carbon monoxide
If a gas furnace is part of the plan, ask how it will vent. For a sealed-combustion furnace with plastic pipes, ask where those pipes will leave the house, how far they will sit from windows, doors and the ground, and how they will be kept open when snow drifts against the wall. If the old furnace shared a chimney with a water heater, ask what happens to the water heater's venting once the furnace no longer uses it. Ask for a combustion and carbon monoxide test at start-up, with the readings on paper, and ask where carbon monoxide alarms would be useful in your house.
License, permit and coverage questions
- What state license or registration, if any, covers this work, and what is the number?
- Which city permits does the installation need, who pulls them, and will an inspector come out?
- Can you show proof of liability coverage and workers' compensation? Your own insurer can help you read the certificate.
- Will your own employees do the installation, or a subcontractor?
- How will the refrigerant in the old equipment be recovered?
Lining up the bids
Copy each proposal onto one sheet under matching headings: model numbers for every piece of equipment, the efficiency ratings of the matched indoor and outdoor pair, the load calculation result, the heating arrangement and how it is controlled, venting work, duct testing and repair, the thermostat, removal of the old equipment, permits and inspection, the start-up readings you will be given, and the written parts and labor warranties. Where one bid leaves a heading blank, ask about it before comparing totals. A short bid that skips half the headings is not yet a price you can set against the others.