The variance between HVAC quotes in the same market for the same job can be 40-50% with no quality difference.
What every quote should include, line by line
| Line item | Why it matters |
|---|---|
| Manual J load calc | Sizes the system to your house, not a guess. Required by most rebate programs anyway. |
| Specific make and model numbers, indoor AND outdoor | Heat pumps are split systems: an indoor head (or air handler) and an outdoor condenser, each with their own model number. The efficiency rating (SEER2 / HSPF2) is published only for AHRI-matched pairs, so the indoor and outdoor units must be certified to work together. Swap one and the rating is void, the rebate is denied, and the manufacturer warranty may not cover the mismatch. A quote that names only the brand or only one half is hiding which half. “Mitsubishi MSZ-FS09NA paired with MUZ-FS09NAH” names the indoor head and the outdoor condenser; that’s the level of specificity you need. |
| AHRI matched system certificate | Proves the efficiency rating you’re paying for is real. Required by rebate programs. |
| Itemized labor vs equipment | If labor is bundled into “total install cost” with no breakdown, you can’t compare apples to apples. |
| Electrical work scope | New circuit, disconnect, panel upgrade if needed. Should be specified, not hand-waved. |
| Permits | Should be included. If a contractor wants you to pull permits yourself, that’s a red flag. |
| Warranty terms | Manufacturer warranty (usually 10-12 years on parts) AND labor warranty. Get both in writing. |
| Refrigerant type | R-454B or R-32 for new installs in 2026. R-410A is being phased out. |
| The misc line | The stuff that quietly walks off the quote and reappears as a “small change order” on install day. Make sure each of these is named in writing: thermostat (brand + model), outdoor mounting bracket or wall stand, pad or platform (concrete pad, ground stand, snow legs in climate zone 5+), line set cover (the white channel from indoor to outdoor; without it, your wall looks like a service truck), condensate drain or pump, disconnect switch (required by code at the outdoor unit), vibration isolation pads, surge protector, Wi-Fi adapter if you want remote control, removal and disposal of the old equipment, and permit fees. |
Red flags
- No Manual J. Sizing by square footage rule of thumb or “matching what you had” leads to oversized systems that short-cycle and underperform.
- Pushing single-stage equipment for a heat pump install. Variable-speed inverter systems are the standard for heat pumps. Single-stage is gas furnace thinking.
- Recommends Nest for a heat pump. Nest’s aux heat staging is documented as problematic with heat pumps. A contractor who’s actually installed many heat pumps will know to spec an Ecobee. See 3.1 Pull the Right Levers.
- No mention of weatherization. A good contractor will ask about insulation before sizing. A great one will say “you should weatherize first, then we size smaller.”
- Vague on cold-climate performance. If you’re in climate zone 5+ and the contractor can’t tell you the heat pump’s rated output at 5°F (or 17°F, the standard HSPF2 test temperature), they don’t understand the product.
Questions to ask, in this order
- How many heat pump systems have you installed in the last twelve months? (20+ for a specialist, 5+ minimum for any contractor.)
- Are you on the participating contractor list for [your state program]? (If no, you may forfeit the rebate.)
- What’s your Manual J methodology? (Looking for software-based, takes inputs from your specific home.)
- What thermostat will you spec, and why?
- What backup heat strategy do you recommend for [your climate zone]?
- What’s the warranty on labor specifically, separate from manufacturer parts warranty?
- Will you handle the rebate paperwork, or is that on me?
If a contractor balks at any of these questions or gives vague answers, get the next quote.