Covered on paper, decided by the cap
Heating and cooling appears on the covered-item list of essentially every home service contract sold in the United States, and that is the least useful thing anyone can tell a buyer. The grant is broad. The dollar limit attached to it is not, and on a system replacement that limit is what the owner pays out of pocket.
The reason is structural. These contracts and the home inspection standards both slice the heating and cooling system into components, and obligations attach at the component level. Neither deals in whole systems. A contract that agrees to replace a condensing unit has not agreed to replace the evaporator coil matched to it, the refrigerant line set between them, or the pad it sits on, and several published forms say so in terms.
Capacity is measured in tons, where one ton equals 12,000 BTU per hour, and every component in that chain is a separate line in the contract carrying its own conditions.
What the covered-item list grants, and the ceiling inside it
The grant language is generous, which is why it gets quoted in marketing and rarely read past. One national sample plan agreement dated July 2024 covers "All parts and components of permanently installed heating systems up to a 5 ton capacity" across forced air, geothermal, package units, heat pumps, mini-splits and electric baseboard, with a parallel air conditioning list "up to a 5-ton capacity, including the condensation line." A widely used buyer-seller form covers "Mechanical parts and components of all centrally ducted air conditioning systems," then itemizes compressors, condensers, coils, fan motors, capacitors, relays, reversing valves, refrigerant, the filter dryer and thermostats.
Read that itemization as a lawyer would. It is a closed list: anything mechanical not named is arguably not granted, and the general exclusions that follow narrow what is. The correct reading order for a home service contract is backwards - general exclusions first, per-item limits second, covered-item list last. Two general exclusions bite hardest here: improper sizing, where one agreement provides that a breakdown occurring "because it is the wrong size for your Covered Home based on manufacturer and/or industry standards" is not covered, and mismatched systems, excluded by one buyer-seller form and expressly treated as a covered cause by another national agreement, so this term has to be read in the contract actually on offer.
The tonnage ceiling is a definition, not a dollar cap. Both forms above stop at five tons, one stating a "Maximum of five (5) ton capacity." A larger system, ordinary in a big house in a hot climate, falls outside the covered-item description entirely, so no cap applies because no coverage does. Tonnage is stamped on the outdoor unit data plate and can be checked before signing anything.
The per-item limit is the number that settles the claim
These contracts limit liability per covered item, per term. The figures below come from specific published documents with their dates rather than industry averages, and the mechanism matters more than the amounts, which change with every form revision.
| Limit type | Published example |
|---|---|
| Standard per-item limit | "The Covered Item Limit is $5,000" (national sample agreement, 2024) |
| Per-item limit, all-inclusive | "Our maximum liability is $3,000 per 12-month period for each Covered Item for access, diagnosis, and repair or Replacement" |
| Sub-capped equipment classes | $1,500 for glycol, hot water and steam circulating heat and for geothermal and water-source heat pumps (2024 form; a 2019 Texas form caps the same class "Up to $1,500") |
| Aggregate sub-cap | "Maximum of $1,500 in the aggregate per Agreement term, per covered property for geothermal or water source systems" |
Two consequences follow. Where the cap expressly absorbs "access, diagnosis, and repair or Replacement," diagnostic visits and drywall work come out of the same pot as the equipment, so the money left for the machine is whatever survives. And a per-item limit in the low four figures does not buy a modern matched split system installed in most markets. The contract is not lying when it says the system is covered; it is describing a contribution, and the buyer hears a replacement.
Access caps stack on top of the equipment cap
Getting to the equipment is priced and capped separately from fixing it. This is the second limit, and it surprises owners of finished basements, encapsulated attics and slab-on-grade houses.
- One national agreement provides coverage "for access to a Covered Item through one layer of unobstructed drywall" and returns the opening only "to a Rough Finish" - unpainted, untextured, unmatched. Access through concrete is separately capped at $1,000.
- Another pays "up to $500 to provide access to Covered Items through roofs, unobstructed walls, ceilings or floors, concrete covered, embedded, encased or otherwise inaccessible Covered Items."
- A 2019 Texas form states in capitals that the company "IS ONLY RESPONSIBLE FOR PROVIDING ACCESS FOR COVERED CENTRAL AIR CONDITIONING REPAIRS THROUGH UNOBSTRUCTED WALLS, FLOORS OR CEILINGS," and caps slab access at $500.
The word doing the work in all three is unobstructed. A line set buried in a chase behind cabinetry, cast into a slab, or sitting above closed-cell foam is obstructed by design, and the obligation shrinks to a few hundred dollars of demolition allowance - after which a rough-finish clause leaves the owner paying for tape, texture and paint on every opening cut.
What a general inspection is required to do, and the gap it leaves
Inspection duties come from a standard of practice: InterNACHI's Residential Standards of Practice, the ASHI Standard of Practice, or in licensed states an administrative rule. They are narrower than buyers assume, and narrow in one specific place.
InterNACHI section 3.4 requires the inspector to inspect the heating system "using normal operating controls," describe the energy source, heating method and thermostat location, and report as needing correction a system that "did not operate" or was "inaccessible"; section 3.5 repeats the structure for cooling. ASHI sections 8 and 9 require the inspector to "open readily openable access panels" and inspect installed heating and cooling equipment and their distribution systems (InterNACHI Residential Standards of Practice).
Then the same documents withdraw the part that matters. ASHI 8.2 and 9.2 provide that the inspector need not determine "heat supply adequacy and distribution balance," "the adequacy of combustion air components," or "cooling supply adequacy and distribution balance." ASHI 13.1 adds that the inspector need not operate systems "that are shut down or otherwise inoperable" and cannot determine "the remaining life expectancy of systems and components." ASHI 13.2 excludes anything "not readily accessible," defined in section 14 as available for visual inspection without "moving of personal property, dismantling, destructive measures, or actions that will likely involve risk to persons or property." Licensed states demand more: Texas rule 22 TAC 535.230 requires reporting as deficient inoperative units, gas leaks in heating equipment, vent and draft-hood problems, damaged duct systems and "absence of air flow at accessible supply registers."
The structural gap. Every standard reviewed excludes sizing, capacity, adequacy and distribution balance from the inspector's required scope - precisely the condition an improper-sizing exclusion turns on. The inspection the buyer paid for is not required to detect the defect that will later defeat the claim, and neither document says so. Closing that gap takes a Manual J load calculation, ordered separately from an HVAC contractor.
Service life: two authoritative charts that disagree
Buyers want a number for how much life the equipment has left. Two respected sources publish numbers and they conflict materially, so quoting one alone produces false confidence in whichever direction it points.
| Component | InterNACHI chart (years) | ASHRAE median service life (years) |
|---|---|---|
| Central air conditioner | 7-15 | 19.0 (split DX system) |
| Condenser | 8-20 | 15.0 (packaged DX, air-cooled) |
| Furnace | 15-25 | 31.0 (residential furnace, packaged condensing unit or heat pump) |
| Heat pump | 10-15 | 14.0 air-to-air; 21.0 water-source |
The InterNACHI figures are a planning estimate, published as "determined through research and testing based on regular recommended maintenance and conditions of normal wear and tear" (InterNACHI life expectancy chart). The ASHRAE figures are survey medians from 344 matching buildings and 27,752 equipment units, weighted toward commercial and institutional stock, measuring observed replacement events. Do not average them. Treat both as ranges rather than a due date - and note that no inspector working under ASHI may give you a remaining-life figure at all.
What a buyer checks, and the window for checking it
Almost every HVAC coverage failure traces to something knowable before the contingency period closes.
- Identify which contract you hold. Direct-to-consumer forms commonly state that "COVERAGE STARTS 30 DAYS AFTER RECEIPT OF AGREEMENT FEE"; real-estate-channel forms routinely show a waiting period of zero days. Same brand, different documents - and a 30-day gap right after closing is exactly when a neglected system fails.
- Read the general exclusions before the covered list. Mismatched systems, improper sizing, modifications, rust and lack of maintenance all live there, and they override the itemized grant.
- Check tonnage and sub-caps against the equipment on site. Five tons and geothermal are the two places where a system that looks covered is not.
- Ask the seller for the manufacturer warranty registration, often worth more than the service contract and commonly forfeited by non-registration or non-transfer.
- Do not buy a service contract to solve a problem the inspection already flagged. A report recommending HVAC evaluation is close to a written record of a pre-existing condition.
Who regulates the contract matters too, because it determines where a complaint goes. These agreements usually declare themselves not to be insurance - one California form states flatly "THIS PLAN AGREEMENT IS NOT A CONTRACT OF INSURANCE" - but Florida regulates home warranties under its Insurance Code, chapter 634, Part II. Texas moved oversight of residential service companies from the Texas Real Estate Commission to the Texas Department of Licensing and Regulation on September 1, 2021, and older forms still in circulation print the superseded agency's address.
The public enforcement record is specific about where HVAC claims break. New Jersey's Division of Consumer Affairs alleged that one national provider "used deceptive tactics to deny consumers' claims," including requiring "multiple years' worth of maintenance records" before approving coverage, and settled for $779,913.93 on June 15, 2015. Arizona sued the same company in 2019 over complaints that it "failed to replace air conditioning units and other home appliances it had advertised as being covered"; an $11.8 million judgment was entered January 23, 2026, with the company denying wrongdoing (Arizona Attorney General announcement). Those records identify the pressure point: service records, produced on demand, deciding whether a failure counts as wear and tear or neglect.
Frequently Asked Questions
Does a home warranty cover HVAC replacement or only repair?
Published contracts obligate the company to repair or replace at its own option, subject to the per-covered-item dollar limit, and that limit is the operative term. Where a form caps liability at $3,000 or $5,000 per covered item, and the same clause makes the cap absorb access and diagnosis, the outcome on a system replacement is a contribution rather than a replacement. The company also chooses the contractor and the equipment.
What is the dollar cap on HVAC coverage?
There is no single industry figure, and any page quoting one is guessing. Published forms reviewed here state limits such as $5,000 per covered item in a 2024 national sample agreement and $3,000 per covered item per 12-month period in another, with sub-caps of $1,500 for geothermal, water-source, hot water and steam circulating systems.
Caps are revised with each form version and vary by state and tier. Look for "covered item limit" or "maximum liability," and check whether access and diagnosis sit inside it.
Is a system larger than five tons covered?
In the forms reviewed, no. Both a 2024 national sample agreement and a widely used buyer-seller form limit covered heating and air conditioning to a maximum of five tons of capacity. That is a definitional boundary rather than a dollar limit, so an oversized system is not covered up to the cap - it is outside the covered-item description. Capacity appears on the outdoor unit data plate, often encoded in the model number, and houses with two systems should be checked unit by unit.
Will a home inspection tell me whether the HVAC is the right size for the house?
No, and every standard says so. ASHI 8.2 and 9.2 provide that the inspector is not required to determine heat supply adequacy and distribution balance or cooling supply adequacy and distribution balance, and no standard requires a load calculation.
That matters because improper sizing is an express exclusion in more than one home service contract. Answering the question takes a Manual J load calculation from an HVAC contractor - a separate engagement, and one that has to be ordered inside the inspection contingency period to be useful.
Can I buy a home warranty after the inspection reports an HVAC problem?
You can buy the contract; collecting on that item is another matter. Contracts exclude pre-existing conditions in terms such as "Known or unknown pre-existing conditions are not covered," and one national form excludes breakdowns existing before the plan start "that were either known by you or were reasonably detectable by you." An inspection report in the buyer's hands is documentary proof of both. The remedy for a flagged system lives in the purchase contract - a repair request, a credit or a price adjustment inside the contingency window.
How long should an HVAC system last?
The honest answer is a range, and the two most cited sources disagree. The InterNACHI chart gives 7-15 years for a central air conditioner, 8-20 for a condenser, 15-25 for a furnace and 10-15 for a heat pump; ASHRAE's database reports medians of 19.0 years for a split DX system and 31.0 for a residential furnace, packaged condensing unit or heat pump. They measure different populations, so averaging them describes nothing, and an ASHI inspector is barred from stating remaining life expectancy at all.