Service guides

HVAC service guides: what each job involves

We offer no HVAC services. These guides explain what each job includes, what sets its price, and what a quote must say.

Updated September 2026 · Data as of Sources dated on each guide

Written by HYRE HVAC Research Desk Primary-source research, data analysis and fact checking

9 guides published The count is what exists, not what is planned

90-100% of systems had some fault, ducts included DOE review of 44 field studies, June 2018

0 jobs HyreHVAC performs We are a research desk and a referral site

What these pages are for

Each HVAC job on this list is decided by a measurement: a static pressure reading, a duct leakage test, a refrigerant charge check or an electrical load calculation. Each costs a fraction of the work it might make unnecessary, and each is often skipped.

HyreHVAC sells no equipment, so these guides can say which measurement settles which question.

The guides

Nine guides. Each is written against primary sources with retrieval dates, and each says where its evidence stops.

Repair Diagnosis Heat pump repair Reversing valves, defrost controls and auxiliary heat are the three things an air conditioner does not have — and the most-reported heat pump fault is a machine working correctly. What fails, what measurement separates the candidates, and why a refrigerant top-up is a diagnosis of a leak. Read the guide 50 lb Diagnosis Refrigerant leak detection and repair The 30-day EPA repair clock quoted at homeowners attaches to appliances holding 50 pounds or more, which a home system is not. What the rules actually require, how a leak is located, and why the R-410A installation deadline people still cite was removed. Read the guide Ducts Seal, repair or replace Ductwork installation and replacement Duct leakage was found in 90-100% of systems DOE reviewed and sealing them returned more than most equipment upgrades. The three jobs that all get called "ductwork", what a code official inspects, and why new metal on the old layout is the expensive way to keep your problem. Read the guide 4 causes Comfort HVAC zoning systems Upstairs hot and downstairs cold has four common causes and dampers address one of them. What zoning does, why an oversized system gets worse when you zone it, and the bypass damper question that decides most quotes. Read the guide ERV/HRV Fresh air Balanced ventilation: ERV and HRV The choice between them is a moisture decision about your house, not a map of climate zones — an ERV transfers water vapor and an HRV does not. Plus the reason ventilation is EPA’s second strategy rather than its first. Read the guide Report Before you buy HVAC inspection The home inspection standard does not require the inspector to check heat exchangers, or to determine whether the system is sized right for the house. A separate HVAC inspection is, in practice, a purchase of the other side of that published boundary. Read the guide IAQ Assessment Indoor air quality assessment EPA ranks source control first, ventilation second and air cleaning third — close to the reverse of the order these services are sold in. What an assessment can establish, when it is worth buying, and the one test EPA actually urges for every home. Read the guide 60% Moisture Whole-home dehumidifier installation Buy a hygrometer before you buy capacity. EPA publishes the humidity ceiling and the ideal range, and a week of readings tells you whether you have a problem at all — or whether the water is coming from something a dehumidifier will never out-run. Read the guide Panel Electrification Panel capacity for electrification A load calculation, not the number on the main breaker, decides whether your service can carry a heat pump. And "panel upgrade" is two jobs with two owners — the second of which, in the one study that separates them, customers reported taking six to nine months. Read the guide

The measurement comes before the money

Read the guides together and the same shape appears in each. There is a cheap measurement that settles the question, a much more expensive purchase that is offered instead, and a scope of work whose completeness you can check without knowing anything technical.

On a repair, the measurement is a reading — capacitance against the rating, superheat or subcooling where charge is claimed, static pressure where airflow is claimed.

You do not have to interpret any of them. Asking whether they exist is the whole test, and a technician who took them will read them out without hesitation.

On ductwork, the measurement is a static pressure reading and a duct leakage number. Together they cost a small fraction of a replacement and they routinely show that sealing, not replacement, is the job.

Where replacement genuinely is the job, the deliverable is a design — Manual J: Residential Load Calculation, 8th edition for the load, Manual S: Residential Equipment Selection for the equipment, Manual D: Residential Duct Systems for the ducts.

DOE’s own code field-study form records the first two as an inspected item: “Heating and cooling equipment is sized per ACCA Manual S based on loads calculated per ACCA Manual J or other methods approved by the code official”.

On electrical capacity, the measurement is a load calculation performed by a licensed electrician against the equipment’s nameplate figures. It costs very little relative to a service upgrade, and it frequently finds capacity that a driveway estimate assumed was absent.

HyreHVAC analysis: None of this implies bad faith. Measuring is slow, dirty, hard to photograph and difficult to sell against a competitor who has already quoted a number.

It is simply that the incentives of somebody who sells equipment and the interests of somebody who owns a house diverge at exactly the point where a measurement would decide between them — and we sell no equipment, so these pages are free to say "measure it, and you may not need to buy anything".

Five questions that work on any HVAC quote

Distilled from the guides. None requires technical knowledge, and each one closes a specific gap that turns two bids into non-comparable documents.

What is the named cause, as opposed to the symptom?

"Not cooling" is the complaint you telephoned in. A cause can be checked afterwards; a symptom cannot. This single question separates a diagnosis from a part swap more reliably than any other.

Which measurements support it, and may I have the numbers?

Readings are a by-product of doing the work rather than an extra. Their absence does not prove anything on its own, but combined with a missing cause it is a pattern worth acting on.

What load calculation is this sized against, and may I have a copy?

Any quote involving new equipment or new ducts should rest on a room-by-room load calculation. Nominal tonnage is a marketing category. If nobody has calculated the load, the size came from whatever was there before — which is how an oversizing error propagates through three generations of equipment.

What is explicitly excluded from this price?

Ductwork, electrical work, permits, utility charges, drywall repair, disposal and commissioning are the usual omissions, and each is capable of being a large number. The cheapest of three bids is frequently the one with the shortest scope rather than the best price.

What happens to the schedule if the inspection or the utility says no?

Permits, inspections and utility applications are the parts of a project nobody controls. Asking the question before signing converts a surprise into a plan, and on electrification projects the schedule is more often the binding constraint than the money.

What we do not do, and where these guides stop

HyreHVAC is a research desk and a referral site. We do not install, service or sell HVAC equipment, we do not perform electrical work, we do not dispatch technicians, and we hold no dataset of quotes, invoices or completed jobs.

Nothing on these pages is a price we have observed. That is also why they are free to conclude that the right answer is to do nothing.

Three specific boundaries are worth stating on the hub rather than repeating on every page. We publish no invented prices: Where we cannot source a figure, we describe what drives it and point at a calculator you can put your own quote into.

We give no DIY instruction on electrical, gas or refrigerant work. The panel guide names that boundary in its first screen rather than in a footer, because a disclaimer at the bottom of a page is not a safety measure.

And we attribute research to the desk, never to a person: Every analysis on this site is the HYRE HVAC Research Desk’s; where a claim belongs to somebody else, they are named and dated.

Questions

Does HyreHVAC do this work?

No. HyreHVAC is a research desk and a referral site. We do not install, service or sell HVAC equipment, do electrical work or dispatch technicians, and no one pays for placement. If you want quotes, we can follow up about local HVAC companies. Your details go to no one unless you agree.

How do I compare three quotes that all say different things?

Not on price until they describe the same scope. Check what each includes for ductwork, electrical work, permits, disposal and commissioning, which load calculation each is sized against, and which measurements were taken. Our quote comparison worksheet runs four completeness checks across three bids.

Which guide should I read first?

Heat pump repair, if something has failed: it separates faults from normal behavior first. Ductwork, if a room has never been comfortable, since that is a design problem. Panel capacity, if you are moving from gas or oil to a heat pump, because it has the longest lead time.

Written and audited by

HYRE HVAC Research Desk

Primary-source research, data analysis and fact checking

We are a research desk, not a sales floor. We read the federal microdata file, the statute or the manufacturer data sheet ourselves, and we publish the figure with the document it came from and the date we retrieved it.

Where a number cannot be traced to a primary source, we publish the shorter page and say what we could not verify.

The counts below are generated from the published pages themselves, last counted September 28, 2026, and they are what we have actually published rather than what we intend to.

13: studies published
12: federal sources read and cited
8: studies published with their full dataset as CSV
51: jurisdictions reproduced against EIA’s own tables

How this desk works

Primary sources only. Federal data comes from the agency that collects it, in the file that agency publishes. We do not cite an article that cites a source; we download the source and compute the figure ourselves.
We validate against the agency before we publish. First, we use each federal microdata file to reproduce the agency’s own published tables. Our cooling research reproduces EIA’s state estimates and standard errors for all 51 jurisdictions. That check caught a variance formula that was off by a factor of four.
Every estimate carries its uncertainty. These are survey figures, not counts. Standard errors are computed from the replicate weights the federal file supplies and printed beside the estimate. An estimate too imprecise to publish is reported as such rather than printed.
Nothing is typed by hand. Prose, tables and charts all read from one dataset built by script, so a number in a sentence and the same number in the table below it cannot disagree.
We publish the data, not just the conclusion. 8 of our 13 studies offer the full computed table as a CSV download on the page, so you can check the analysis or disagree with it. A study without a row-level dataset gets no download link and claims none in its structured data.
We correct in public. Where we have published a figure wrongly we fix the figure, rewrite any analysis that rested on it rather than patching the number underneath it, and leave a dated correction note on the page.
We do not install or sell HVAC equipment, and we take no payment for placement, ranking or a favorable mention. Nobody buys a position on this site.

Data as of Sources dated on each guide. Authorship on this site is organizational: the analysis belongs to the desk rather than to a named individual, and we do not publish credentials we do not hold. Our editorial policy sets out how we source, date and correct what we publish.

Ready to compare quotes?

Read the relevant guide first. It tells you what the quote has to contain. Then tell us the system, the symptom and the zip code, and we will follow up about local HVAC companies. Sending an inquiry is not a service call.

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