See the real value of a new HVAC system.
True costs, rebates, savings, and payback — a complete cost-benefit analysis with every assumption on screen — so the repair-or-replace decision is yours, made with confidence.
The decision: repair or replace
What the old unit really costs
Energy at its degraded efficiency plus rising repairs — not just this year’s repair bill. Repair-or-replace guide →
What a new system saves
Savings scale with the efficiency jump and how hard your climate runs it. Efficiency ratings guide →
Your net cost after rebates
The quoted price minus utility and state rebates — often thousands below sticker. 2026 rebates guide →
When it pays for itself
The year total savings overtake the net cost — under ~8 years is usually a clear yes. How payback works →
The HVAC savings calculators
Bills-based or ZIP-based · every assumption editable · print-ready results
Cooling savings
SEER → SEER2For central AC and heat pumps in cooling mode. Uses your actual utility bills, or your ZIP’s climate hours and your utility’s real summer electricity rate. Every assumption is on screen and editable.
Heating savings
AFUE · HSPF2For gas furnaces — and the question of the decade: high-efficiency furnace, or switch to a heat pump? Compares gas and electric operating cost on the same chart using your gas and electricity prices.
The benefits that never
show up on a bill
The calculators measure dollars because dollars can be measured. But a year in, most people talk about something else first: the house finally feels right. If your payback is marginal, this is what you're actually buying with the difference.
Read the full comfort guideUnderstand before you buy
The terms, the math, and the trade-offs
Check the math yourself
Most "savings calculators" are lead-capture forms with a marketing model behind them. This one is the opposite: an education tool with the model in the open. Every result ships with a "math behind these numbers" panel that recomputes your inputs step by step, and where a judgment call existed, we took the side that understates your savings.
Climate comes from five years of per-ZIP weather reanalysis, electricity rates from NREL/EIA-861 utility data, grid carbon from EPA eGRID — all cited on the methodology page. If you find an error, we want to know.
- Conservative by designThe keep-vs-replace model assumes your old unit survives all 15 years without a catastrophic failure — generous to keeping it.
- Every input stays on screenZIP lookups prefill values; nothing is hidden. Edit the rate, the hours, the escalation — the model updates live.
- No leads, no affiliationsWe don't sell equipment, capture contacts, or take manufacturer money. The recommendation is whatever your numbers say.