HVAC Knowledge Base
278 in-depth, original HVAC guides written by working techs — refrigerant charging, electrical, heat pumps, gas heat, airflow, and field diagnostics. Free to read, no signup.
Field Tools
HVAC Age Decoder
Paste a serial, get the manufacture date, capacity, and remaining useful life across 120+ HVAC brands. No login, no upsell.
TXV Diagnostic Checklist
Six-step interactive checklist for TXV stuck-open vs stuck-closed. Prints a customer-ready proof report at the end of the call.
20,000+ Equipment Profiles
Specs, refrigerant, electrical, and field notes for over 20,000 HVAC models. Use it to validate replacements before quoting.
Manufacturer Error Codes
Searchable error code library across major HVAC brands. Tie a code back to the model, then to the right diagnostic step.
LED Blink Codes
Decode furnace and control board LED blink codes so you stop guessing and start fixing on the first visit.
HVAC Tech Blog
Field-tested guides on TXVs, superheat / subcooling, refrigerant transitions, and diagnostics that close jobs.
Wet-Bulb & Target Superheat Calculator
Type the indoor wet-bulb and outdoor dry-bulb, get the target superheat charge-to value off the standard fixed-orifice chart. Built for the truck.
Interactive PT Chart
Pressure↔temperature for R-410A, R-32, R-22, and R-454B. Bubble/dew points off the verified ASHRAE chart for charging and superheat/subcool work.
Capacitor Tolerance Check
Enter rated and measured microfarads, get an instant pass/fail with the exact percent deviation against HVAC tolerance bands.
Capacity Estimator
Rough cooling/heating BTU from square footage for a quick gut-check — with an honest reminder to run a full Manual J before quoting.
Manual J Load Calculator
Free room-by-room residential load calc with a map-traced footprint. Permit-grade sizing without the desktop software.
Air Distribution Part 1 — Airflow & Measurement
NCCER-aligned field guide on airflow, duct pressure, residential distribution layout, and every instrument a tech uses. Tap Listen to hear it while you drive.
Air Distribution Part 2 — Equipment & Materials
Blowers vs fans, direct-drive vs belt-drive, the fan laws, galvanized vs flex duct, and the difference between a diffuser, register, and grille. Studio voiceover included.
Air Distribution Part 3 — Design & Energy
The five residential duct layouts, sizing room CFM for heating vs cooling, IECC duct insulation, vapor barriers, mastic sealing, and the Duct Blaster test.
Brand Age Decoder Guides
Brand-specific decoder workflows so the tech on site knows exactly where the manufacture date lives in the serial — before they call the office.
Carrier
Covers Carrier, Bryant, Payne, Heil, and 9 more ICP family brands. WWYY serial pattern explained.
Trane
Covers Trane, American Standard, Ameristar. How to read the year-letter and verify with the data plate.
Goodman
Covers Goodman, Amana, Janitrol, QuietFlex. YYMM-first serial pattern, common gotchas.
DUCANE
Allied Air family. Where to find the data plate, common serial layouts, warranty notes.
Tempstar
Tempstar / ICP family variants. Workflow for legacy and modern serial formats.
Daikin
Daikin and legacy McQuay families. Why model + serial together is critical for Daikin lines.
Turn Free Diagnostics Into Paid Jobs
Use the free HVAC IQ Pro tools to close the diagnosis. Use LaunchMyHVAC to turn that diagnosis into a same-day estimate, an on-site invoice, and a paid customer. Free plan available — no credit card.
Operator Playbooks
Get Paid Faster
Quote on site, send the invoice from the truck, take card or ACH before you leave. The fewer days between work and money, the healthier the shop.
Stop Repeat Trips
Pair the age decoder + TXV checklist + equipment profile so the tech walks in with the spec sheet, the likely failure, and the customer-ready proof report.
Frequently Asked Questions
Are these HVAC resources actually free?
Yes. The HVAC age decoder, TXV diagnostic checklist, brand serial guides, error codes, and equipment profiles are free to use without signup. LaunchMyHVAC also offers a free CRM plan.
Do I need a LaunchMyHVAC account to use the resources?
No. The resources hub is public. You can use any tool or guide without an account. A LaunchMyHVAC account is only needed when you want to turn diagnostics into customer-facing estimates, invoices, and dispatch.
Who builds and maintains these resources?
The HVAC IQ Pro and LaunchMyHVAC teams. The age decoder and equipment profile database are powered by HVAC IQ Pro, the technician intelligence platform. LaunchMyHVAC is the HVAC-first CRM that turns this field knowledge into paid jobs.