Published comparison · our own test · October 25, 2026

Free HVAC self-check tools, run through the same scenarios

We say our free diagnostic is the best free homeowner HVAC self-check we could find. A claim like that needs a published test, so here are two: every tool we could find in the category run through the same scenarios on a fixed rubric (Part 1), then twelve real cases from our own service files run through the tools that could take them and scored blind (Part 2). The rubric, the cases, the scores, the raw observations, and the places other tools beat ours.

This is Polar Breeze's test of its own tool against others. It is not independent, nobody was blinded, and no equipment was measured. Treat it as a checkable argument, not a certificate. Anything here you can disprove, tell us and we will change the page.

The category

Free, browser-based, homeowner-facing HVAC self-check tools that take a symptom or a reading and return guidance, found by web search in the United States on October 25, 2026. Each was run live in a desktop browser with the same scenarios. Tools that lock results behind a contact form, failed to load, or were gone are listed but not scored.

Not in the category, on purpose:

measureQuick, Danfoss Ref Tools and other instrument-connected professional apps. Different category: they read probes a technician owns. We do not claim to out-diagnose instruments.
Repair-or-replace calculators (Trane, HVAC.com). They take an age and a repair cost; they do not look at symptoms.
Of four tools named in a third-party audit we received, one (iHVAC Dale) was found and is scored above; the other three ("HomeownerPal", "Central HVAC Troubleshooter", "Bay Area Climate Control") could not be found on the web on the test date and are not scored.

The scenarios

Gas smell or CO alarm selected: what does the screen say to do first, and what else is on it?
A breaker that keeps tripping: is a reset suggested, is a part named?
Ice on the coil, alone and together with another fault: is the thaw instruction present, does it survive?
A heat pump blowing cool air in heating: is defrost explained, is the pattern asked?
Short cycling: is it cleared by anything, or kept open?
A normal temperature reading: what is concluded from two numbers alone?
What can you take with you: copy, image, nothing?

The rubric

Seventeen criteria, 0 to 2 points each, 34 points possible. The definitions are fixed before scoring and apply to us the same as to everyone else.

#	Criterion	What it measures	How it scores
C1	No signup gate	Results appear without an email, phone or account.	2 = nothing asked; 1 = optional contact; 0 = results locked behind a form.
C2	Equipment identity	Separates gas furnace, electric heat, heat pump, dual fuel and ductless before giving fuel-specific advice.	2 = all separated; 1 = partly lumped ("gas or electric"); 0 = one bucket.
C3	Takes measurements	Accepts return and supply air temperatures and interprets them with stated limits.	2 = yes, with limits stated; 1 = reference ranges only; 0 = no measurements.
C4	Honest uncertainty	Says "not established" or lists possibilities instead of naming a failed part from symptoms alone.	2 = never names a part without support; 1 = lists causes but then names one; 0 = asserts a part.
C5	Gas smell / CO alarm	Leave first, no switches or phones inside, call from outside, nothing else competing on that screen.	2 = all of that; 1 = evacuation present but incomplete or buried; 0 = absent or tells you to operate things first.
C6	Breaker keeps tripping	Leave it off, no further resets, no part named from the symptom.	2 = yes; 1 = partial; 0 = reset advice, or symptom not offered.
C7	Ice on the coil	Stop cooling, thaw guidance, and the instruction survives when another fault is also reported.	2 = yes; 1 = present alone but lost in combination (or not captured); 0 = absent.
C8	Heat pump cold air	Asks the pattern (does warm return, is the outdoor unit steaming or iced) and explains defrost as normal vs a fault.	2 = asks and explains; 1 = symptom offered, no pattern; 0 = heat pump not distinguished.
C9	Contradiction check	Notices when a reading and a symptom describe different moments and asks to re-measure.	2 = yes; 0 = no (needs measurements to be possible).
C10	No replacement pressure	Does not steer toward a new system from a symptom; cost figures tied to evidence.	2 = none; 1 = cost figures without evidence; 0 = recommends replacement from a symptom.
C11	Safety kept apart from sales	An emergency screen carries no booking, pricing or service-fee prompts.	2 = clean; 1 = a call/book button on the emergency screen; 0 = fees or scheduling in the emergency text.
C12	Case file you can take	Copyable text and a downloadable image of the findings, actions and open items.	2 = both; 1 = one; 0 = none.
C13	Teaches as it goes	Explains what a tech measures and how the system works, on the result.	2 = interactive education; 1 = text sections; 0 = none.
C14	Free checks first	Safe homeowner checks before a paid visit, never including opening panels or repeated resets.	2 = yes; 1 = some; 0 = none.
C15	Says what it is	States it is screening, not a diagnosis, and who or what produces the result.	2 = clear disclaimer and AI/human disclosure; 1 = disclaimer only; 0 = none found.
C16	Scope beyond central HVAC	Boilers, water heaters, refrigeration, mini-splits.	2 = two or more extra categories; 1 = one; 0 = none.
C17	Once vs repeated trip	Asks whether a breaker tripped once or every time before advising.	2 = asks explicitly; 1 = implied by wording; 0 = not asked.

The scores

Tool	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10	C11	C12	C13	C14	C15	C16	C17	Total
Polar Breeze — The Forensic Bay	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	1	1	32/34
iHVAC — Dale (AI triage chat)	2	1	1	1	2	2	1	2	2	1	1	1	1	2	2	1	1	24/34
Patchogue Heating & AC — HVAC Troubleshooter	2	2	0	1	2	2	2	2	0	1	1	0	0	2	2	2	2	23/34
HVAC Calculator Hub — Diagnostic Decision Engine	2	2	0	2	1	2	1	2	0	2	1	0	1	1	2	1	2	22/34
Big Mike's Heating & Cooling — HVAC Symptom Diagnoser	2	1	0	1	2	0	2	0	0	1	1	0	0	2	1	2	0	15/34
Trane — Troubleshooting Guide	2	1	0	1	0	0	0	0	0	2	2	0	1	2	0	1	0	12/34
TradesQuote — Delta T Calculator	2	0	2	1	0	0	0	0	0	2	2	0	1	0	2	0	0	12/34
North Breeze HVAC — Quick Diagnostic Tool	2	1	0	1	0	0	1	1	0	0	0	0	0	2	1	2	0	11/34

Hover a cell for the observation behind it. Full observations per tool are below.

Where ours scored ahead of every other tool

Equipment identity
Takes measurements
Honest uncertainty
Gas smell / CO alarm
Breaker keeps tripping
Ice on the coil
Heat pump cold air
Contradiction check
No replacement pressure
Safety kept apart from sales
Case file you can take
Teaches as it goes
Free checks first
Says what it is

Where at least one tool beat ours

Scope beyond central HVAC — Mini-split added today. No boilers or water heaters — out of scope, and we say so.
Once vs repeated trip — Our symptom is worded "breaker keeps tripping"; the free checks allow one reset only. We do not ask once-vs-repeated as a separate question, Patchogue and HVAC Calculator Hub do.

Things we copied from other tools on the test day are marked in the notes. Credit where it is due.

The observations, tool by tool

Polar Breeze — The Forensic Bay

32/34

Polar Breeze (us), Orem, Utah · diagnostic chunk of Oct 25, 2026 (hash on the tool page) · open

Equipment identity: Central split (asks gas or electric), heat pump, ductless mini-split, dual fuel, packaged, not sure.
Takes measurements: Return and supply sliders, optional nameplate rated rise; bands labeled as screening references; by-feel is an observation, never a number.
Gas smell / CO alarm: Ticking gas or CO replaces the questionnaire with evacuation steps; the case file is emergency-only.
Ice on the coil: Thaw instruction kept with a stopped fan or grinding; becomes fan-OFF passive thaw when trips or an unlocated noise are also reported.
Heat pump cold air: Pattern questions added today after seeing them on HVAC Calculator Hub: cool air returns / stays, steam, iced solid.
Scope beyond central HVAC: Mini-split added today. No boilers or water heaters — out of scope, and we say so.
Once vs repeated trip: Our symptom is worded "breaker keeps tripping"; the free checks allow one reset only. We do not ask once-vs-repeated as a separate question, Patchogue and HVAC Calculator Hub do.

iHVAC — Dale (AI triage chat)

24/34

iHVAC (ihvaconline.com), a referral platform; Dale is an AI chat assistant · as served Oct 25, 2026; one message per scenario, no follow-up turn · open

No signup gate: No signup; the page says so and it held.
Equipment identity: Free text: it takes whatever equipment you name and does not ask gas vs electric or heat pump vs furnace before advising; in the grinding case it assumed what we told it.
Takes measurements: Accepts numbers in chat. Read an 18°F cooling split correctly; on a 74°F furnace rise it said "on the high side" and still listed the flame sensor first, so the number did not drive the answer.
Honest uncertainty: Lists possibilities and says "one possibility" often; but the short-cycle case named the flame sensor first against a limit-code pattern, and the breaker case said "likely low airflow or low refrigerant".
Gas smell / CO alarm: Gas: leave now, no switches or phones, call 911 and the utility from outside, do not re-enter. CO: leave, 911, do not turn the furnace off or hunt for the source. Both clean.
Breaker keeps tripping: Stop resetting, two trips in a row means a fault; capacitor/fan named as possibilities, not asserted.
Ice on the coil: Ice plus clogged filter plus a breaker: turn the AC off and leave it off, replace the filter; no thaw instruction (fan ON, hours) and it followed with a refrigerant-leak possibility.
Heat pump cold air: Explained defrost as normal unprompted, listed the three signs that make it a fault, asked whether warm air returns.
Contradiction check: Warm air at the vents with an 18°F split: said the split is good, something else is going on, asked whether it is calling for cooling right now.
No replacement pressure: Heat-exchanger claim: asked for a written report, a photo with the data plate in frame, a second opinion; then said replacement is often the right call at 12 years and gave install price ranges before any crack was proven. No warranty angle.
Safety kept apart from sales: The emergency reply is clean, but the page under it carries Request provider availability and fair-price buttons.
Case file you can take: Writes a bring-along note you can copy from the chat; no image, no file.
Teaches as it goes: Explains in prose as it goes (what defrost is, what the limit switch does); no interactive teaching.
Free checks first: Safe checks on every answer: filter, returns, thermostat, tubing you can see without opening panels.
Says what it is: States it is an AI educational tool, not an inspection, on the page and under every reply.
Scope beyond central HVAC: Took a boiler question and asked the right first question (cold at the top vs cold all over). Other categories not tested.
Once vs repeated trip: Did not ask once vs every time; it worked from what we told it.

Where it beats ours

Takes a plain-English description of anything; no fixed list to fit your problem into.
Asks a follow-up question after every answer, which is how a real triage call works.
Explained the heat-pump defrost pattern unprompted.

Patchogue Heating & AC — HVAC Troubleshooter

23/34

Patchogue Heating and Air Conditioning, Patchogue, NY · as served Oct 25, 2026 · open

Equipment identity: Gas furnace, electric furnace, heat pump heating and cooling, boiler, mini-split, not sure.
Honest uncertainty: Heat pump not heating with a silent outdoor unit ended at "failed fan motor or capacitor" stated as certain; the repair is tech-level, so the harm is limited.
Gas smell / CO alarm: CO alarm: leave with everyone, do not find the source, call 911 from outside, do not re-enter until cleared. The same screen carries a schedule button and the company phone.
Breaker keeps tripping: Asks once vs every time; repeated trips get "do not keep resetting" and a tech.
Ice on the coil: Frozen coil: system off, fan on, thaw 2–4 hours, then a filter question.
Heat pump cold air: Symptoms include stuck in defrost, aux running constantly, ice on the outdoor unit; follow-ups ask whether the outdoor unit runs.
No replacement pressure: Sample result quotes part ranges; the result screen prints the company's $129 service-call fee.
Scope beyond central HVAC: Boilers and mini-splits covered.

Where it beats ours

Asks once vs every time for a tripping breaker as its own question.
Covers boilers; we do not.

HVAC Calculator Hub — Diagnostic Decision Engine

22/34

hvaccalculatorhub.com (independent calculator site) · page states version 3.0, reviewed Sept 3, 2026 · open

Equipment identity: Six types including electric heat and ductless; the best equipment list in the field.
Takes measurements: No temperature entry; text gives reference ranges and says no single split proves health.
Honest uncertainty: Result shows "Confidence: not measured; onsite verification needed" and lists possible causes.
Gas smell / CO alarm: A safety gate sits in the text above the tool. In the engine itself, selecting the odor/CO flag under "Noise, odor, or electrical concern" still returned an electrical-start result and a booking step; it did not switch to evacuation.
Ice on the coil: Ice plus clogged filter plus a breaker that trips again returned the electrical stop (correct) with no thaw instruction; ice alone was not captured.
Heat pump cold air: Asks whether warm air returns, whether the outdoor coil is steaming or iced, and the thermostat mode. We copied the idea.
Safety kept apart from sales: "Book HVAC Repairs" links sit between the text sections.
Once vs repeated trip: Follow-up offers "breaker trips again after one reset".

Where it beats ours

Asked the heat-pump defrost pattern before we did (we added it the same day).
Offers an electric-heat and a ductless option in the first question; we added ductless the same day.
Publishes a tool policy listing what it will never instruct a homeowner to do.

Big Mike's Heating & Cooling — HVAC Symptom Diagnoser

15/34

Big Mike's Heating & Cooling, Detroit, MI · as served Oct 25, 2026 · open

Equipment identity: Furnace is "gas or electric" in one card; air conditioner is "central AC, heat pump" in one card.
Honest uncertainty: Frozen coil result: good stop and thaw, then "if filter wasn't dirty, you likely have a refrigerant leak" — a leak named from a clean filter.
Gas smell / CO alarm: Gas smell: leave immediately, no lights or electrical, no phone inside, call the utility from outside. Good.
Breaker keeps tripping: No breaker symptom offered for furnace or AC.
Ice on the coil: Turn the AC off now, fan on to thaw 1–3 hours, replace filter, do not restart until thawed.
Says what it is: No disclaimer found on the tool page.
Scope beyond central HVAC: Boilers and water heaters covered.

Where it beats ours

Covers boilers and water heaters; we do not.

Trane — Troubleshooting Guide

12/34

Trane (manufacturer) · as served Oct 25, 2026 · open

Equipment identity: Picks a product category, then one of six symptoms; no fuel question.
Gas smell / CO alarm: No gas-leak or CO guidance on the guide; the only fuel step is checking a shut-off valve.
No replacement pressure: Manufacturer page with no replacement push and a find-a-dealer link only.
Says what it is: No troubleshooting disclaimer found; only a cookie notice.

TradesQuote — Delta T Calculator

12/34

TradesQuote (software vendor) · as served Oct 25, 2026 · open

Takes measurements: Return and supply temperatures plus an indoor-humidity pick that shifts the target band; says a split is a screening check, not a charging method.
Honest uncertainty: Each band comes with likely causes (low refrigerant, dirty coil, restricted airflow) from the number alone.
Gas smell / CO alarm: Temperature-only tool; no symptoms, no safety content.

Where it beats ours

Adjusts the cooling band for indoor humidity; we use a dry-Utah band and say so.

North Breeze HVAC — Quick Diagnostic Tool

11/34

North Breeze HVAC & Refrigeration, Los Gatos, CA · as served Oct 25, 2026 · open

Equipment identity: "Heating" covers furnaces, heat pumps and boilers in one pick.
Gas smell / CO alarm: CO alarm result tells you to turn the furnace and the gas valve off and open the windows before getting out. Utility and CPSC guidance is to leave first and operate nothing. Call 911 is listed fourth.
Ice on the coil: A written AC-freezing guide exists; the quick tool's AC result was not captured. Scored 1, neither credit nor penalty.
Heat pump cold air: Heat pump guides exist (light frost normal, heavy ice a defrost fault); the quick tool lumps heat pumps under heating.
No replacement pressure: CO result: for a furnace over 20 years "replacement is almost always the recommendation". Short-cycling result: a cracked exchanger "typically means full replacement since the part often costs more than a new unit". Most exchangers carry a 20-year-to-lifetime parts warranty.
Safety kept apart from sales: Call-now and request-service buttons on the CO result.
Scope beyond central HVAC: Refrigeration and wine-cellar categories.

Where it beats ours

Covers commercial refrigeration and wine cellars, a different market.

Hamilton Heating & Cooling — AC Troubleshooting Wizard not scored

Results are locked behind a name, email, phone and postal-code form with consent to contractor calls and texts. Not scored; a tool you cannot see without handing over contact details is a lead form.

Adams Air — AC Diagnostics App (Houston) not scored

The app did not load ("problem loading the diagnostics app in your browser"). Not scored.

Ductless Fix — Free HVAC Tools not scored

The page returned HTTP 410 Gone on the test date. Not scored.

Part 2 — twelve real cases, scored blind

Part 1 scores features. Part 2 asks the only question that matters to a homeowner: given what a real person said about a real system, did the tool point where the technician's visit ended up? Twelve cases from our own service files, stripped of names, addresses, brands and invoice details. Each tool got the same homeowner message in one turn (menu tools got the closest menu path, listed in the raw captures). The five outputs per case were stripped of company names and phone numbers, labeled A to E in a fixed shuffle, and handed to a scorer that had never seen the tools and was not told which was ours. The scorer was an AI model given the rubric below, not a human panel; the technician's on-site finding was the answer key.

#	Criterion	0 to 3 points
S	Safety and no-harm	Nothing unsafe; anything that should be stopped is stopped (a grinding motor, an iced coil, a stalled fan, repeated breaker resets).
D	Direction	Points at what the technician actually found, or says it is not established and lists it among the possibilities; names no wrong part as likely.
P	No replacement or sales pressure	No steer to a new system, no unproven cracked-exchanger scare, no fee or booking pitch inside the answer.
N	Next-step usefulness	Concrete, correct, safe homeowner steps that move this case forward, including what to write down for the tech.

Case (what the technician found)	A	B	C	D	E
RC01High-altitude venting / pressure-switch problem (inducer draft and switch setting at altitude), not the igniter.	8	10	6	12	10
RC02High-limit trips from low airflow (clogged filter); fixed with a filter and airflow correction.	8	12	9	12	12
RC03Inducer (draft) motor bearings failing; the pressure switch would not close when the inducer dragged.	9	11	5	8	10
RC04Defrost failure (defrost control / sensor); unit needed to be shut off and thawed, then the defrost circuit repaired.	8	12	7	8	9
RC05Clogged condensate trap backing water into the pressure-switch tubing.	7	11	6	11	8
RC06Airflow starvation from a clogged filter froze the coil; thaw with the fan, new filter, recovered.	10	12	11	7	10
RC07Blower door not seated; the door safety switch cut power.	6	12	6	12	9
RC08Thermostat fan set to ON (continuous fan), nothing broken.	5	10	9	9	7
RC09Failed run capacitor; replaced on site.	4	9	5	6	10
RC10No documented finding; a second inspection found no crack.	6	12	6	11	6
RC11Dirty flame sensor; cleaned on site.	7	12	9	7	10
RC12Duct distribution problem (undersized / leaky upstairs runs), equipment healthy.	4	9	6	12	9
Total of 144	82	132	85	115	110

Each cell is one tool's score on one case, out of 12. Hover a cell for the scorer's one-line reason. Letters: A = Patchogue Heating & AC — HVAC Troubleshooter; B = Polar Breeze — The Forensic Bay; C = Big Mike's Heating & Cooling — HVAC Symptom Diagnoser; D = iHVAC — Dale (AI triage chat); E = HVAC Calculator Hub — Diagnostic Decision Engine. Ranking: Polar Breeze > iHVAC > HVAC Calculator Hub > Big Mike's Heating & Cooling > Patchogue Heating & AC.

The scorer's notes, unedited except for replacing the letters with names

Polar Breeze wins on direction and the absence of sales pressure: it is the only tool that handled the heat-exchanger claim and the condensate trap, and its caution blocks stop iced and grinding equipment. Polar Breeze still loses points for a fixed Ignition verdict that leads with the igniter even when two igniters were already replaced (RC01), the inducer was named in its own evidence (RC03), or the thermostat fan setting was the answer (RC08), and for a run-it-15-minutes boilerplate line that appears even on a stalled condenser fan (RC09) with no stop; its outputs are also several times longer than needed. Dale is the sharpest when it commits (RC01, RC02, RC07, RC12) but repeatedly spends its one turn on a question and misses stops: it told the homeowner to run a grinding inducer to listen, and gave no turn-off or no-chip for an iced heat pump or frozen coil. HVAC Calculator Hub is consistently safe and never pushes replacement, but its fixed categories ignore given evidence (altitude, the door hint, the black filter, the fan-ON setting) and it could not take the contractor-claim case. Patchogue and Big Mike's sit at the bottom because every result carries a $129 fee or $19/month plan pitch, both reach for the cracked-heat-exchanger scare on ordinary no-heat and short-cycle cases, and their menu paths cannot accept the detail that decides most cases (water on the floor, the blower door, a stalled fan, a hot upstairs), so they assert refrigerant or compressor on a healthy system.

Where ours lost points, in the scorer's words

RC01Includes pressure switch/inducer/blocked flue but the verdict still leads with the hot-surface igniter after two igniters were already replaced; checks are generic boilerplate.
RC03Caution block correctly stops the furnace and puts the inducer first with a timing tell-apart, but the headline verdict still says igniter/flame sensor/pressure switch.
RC05Verdict still leads with igniter/flame sensor, but the open items and checks name the condensate trap, say clearing it is a homeowner job and warn not to bypass the float switch.
RC08Verdict is ignition, but the evidence line and free checks do say the thermostat fan may be set to ON and to put it on AUTO.
RC09Nails fan motor or run capacitor, but has no shut-it-off line and the boilerplate tells the homeowner to run it 15 minutes with the condenser fan stalled.
RC12Correctly reads an 18F split as healthy equipment and refuses to quote against it, but never captures the upstairs symptom or names ductwork.

What we changed the same day

A sequence-of-operation question (what you actually watched run: inducer, igniter, flame, blower; outdoor unit silent, humming, running) now drives the verdict, so an inducer that quits before the flame reads as draft, not igniter.
Water on the floor with a no-light or pressure-switch code on a high-efficiency furnace now leads with the condensate trap.
Cool air with the blower running all the time offers the thermostat fan switch (ON vs AUTO) as the first free check.
A stalled outdoor fan now carries a switch-cooling-off caution, and the run-it-15-minutes line is gone from that result.
A new symptom, some rooms much hotter than others, returns a distribution (ductwork) finding with no equipment price and a quote-check that says a bigger unit does not fix it.
A heating noise symptom (grinding, squealing, rattling) with inducer-vs-blower timing, added from the inducer-bearing case.

Re-run of our tool only, after the fixes, scored blind by a fresh scorer as an unnamed sixth tool: 135 of 144. The second scorer's remaining notes: the ignition explanation text still led with the igniter on cases where the verdict had ruled it out, the cold-air case priced a repair before the fan switch was ruled out, and the free-checks list told the owner to run a furnace that would not light or a shut-down heat pump. Those three were changed after the second scoring and gated; they were not scored a third time. Scorer's words: F's main weakness is a generic ignition boilerplate: on every furnace won't-light or cold-air case the Explanation and What-separates-it blocks lead with the hot-surface igniter and flame sensor even when the verdict line has already ruled them out (RC01, RC03, RC11), and on RC08 that boilerplate becomes the verdict, pricing a repair for a furnace whose only fault is the fan switch set to ON. The free-checks list is pasted rather than fitted, so it tells a homeowner to run a shut-down iced heat pump or a non-lighting furnace for 15 minutes and re-measure, and it appears unchanged on the heat-exchanger-claim case where it has no bearing. Safety stops and anti-replacement framing are consistently right; the remaining errors are direction leakage from templates, not unsafe or sales-driven advice. The other tools were not changed and were not re-run; the table above is the first, comparable run.

What this does and does not prove

Part 1 proves how each tool behaved on the stated inputs on the stated day. Tools change; the date is the date.
Part 2 proves how each tool's one-turn answer lined up with what a technician found on twelve real systems. Twelve is twelve; it is not a trial.
Neither proves diagnostic accuracy against equipment a tool has never touched. No tool here, ours included, measured a system. Ours is a screening and teaching tool, and says so on every result.
Part 1 is not blinded; the scorer built one of the tools. Part 2 is blinded as to tool identity, but we chose the cases (from our own files), we ran the tools, and the scorer was an AI model, not a panel of technicians. The pack it saw, the key, and its scores are in our repository.
The claim we make from it is exactly this: on these two tests, on this date, our tool scored highest among the free homeowner self-check tools we could find. Nothing more.
On looks, several of these tools are cleaner and faster to use than ours. That is a fair criticism we have not fixed yet.

Raw captures of each result screen, with the inputs used, the anonymized Part 2 pack, the letter key and the scorer's JSON are kept in our repository under docs/research. If you run a free homeowner HVAC tool that belongs in this comparison, email john@polarbreezeut.com with the link and we will run it through the same scenarios.

Run the free self-check The Yogi Lab articles