IN HVAC Calculator vs EPA 609 Certification Prep
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
IN HVAC Calculator
This app provides HVAC inspection tools and guidelines for home inspectors. It helps estimate equipment age, size, and requirements, giving inspectors confidence in their reports.
- Equipment circuit requirements calculator
- AC tonnage estimation by model number
- HVAC manufacture date lookup
- Combustion air requirements guide
- General HVAC reference information
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Inspector Nation presents a general reference application to provide insight into the world of HVAC equipment inspection. It is never good practice to mention the exact age or tonnage rating in the home inspection report, but having a reference point of age and size gives the home inspector confidence to map out the inspection and set the tone for the report. This application will aid the inspector by providing several HVAC-related inspection calculators as well as guidelines for approximate values for (1) equipment circuit requirements, (2) air conditioner tonnage based on the model number, (3) HVAC manufacture date, and (4) combustion air requirements. Contact us if you'd like to request a feature for a future release!
EPA 609 Certification Prep
Prepare for your EPA Section 609 MVAC certification with focused practice questions, clear explanations, and an offline reference library. Master regulations, refrigerant identification, and safety protocols for the motor-vehicle air-conditioning exam.
- Practice mode with 50 multiple-choice questions
- Explanations and citations for every answer
- Mock exams mirroring the real certification test
- Offline reference library for refrigerants and regulations
- Diagnostic pass/fail analysis against EPA cutoff
- One-time unlock for Pro content
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Preparing for your EPA Section 609 MVAC certification? EPA 609 Certification Prep gives you focused practice for the 25-question, open-book motor-vehicle air-conditioning exam — with clear explanations, CFR and SAE citations, and an offline reference library built for the shop. WHAT'S INCLUDED: Practice Mode - 50 multiple-choice questions covering Section 609 regulations, refrigerant identification, recovery equipment, leak detection, evacuation, retrofits, and hybrid / EV high-voltage safety. - Every answer paired with an explanation and a regulation or SAE citation (40 CFR Part 82 Subpart B, SAE J2788 / J2843 / J2851, and more). - Drill Core 609 topics or MVAC topics separately, or sweep across the whole bank. Mock Exams - Mock 1 — 25 questions, open-book format matching the real Section 609 exam. - Mock 2 — advanced MVAC scenarios: R-1234yf A2L handling, POE oil on hybrid compressors, retrofit compliance, evacuation to 500 microns. - Question overview grid + flag-for-review during the exam. - Section-by-section pass / fail diagnostic against the 84% EPA cutoff. Reference Library (always free) - Refrigerants: R-12, R-134a, R-1234yf, R-744, R-152a — with ODP, GWP, ASHRAE safety class, and service-port quick-reference. - Regulations: Section 609, Clean Air Act, Montreal Protocol, SNAP program, AIM Act. - Recovery Equipment: SAE J2788 / J2810 / J2843 / J2851 / J2845 standards plus the full MVAC service sequence. - Leak Detection: SAE J2791 / J2913 detector standards, common MVAC leak points, repair philosophy. - Safety: refrigerant exposure limits, A2L / A2 flammability, hybrid / EV high-voltage service, PPE, first aid. WHO IS IT FOR: - Automotive technicians preparing for Section 609 MVAC certification - Dealership service advisors needing refrigerant-handling authority - Vocational students and automotive-trade instructors - Independent mechanics servicing R-134a and R-1234yf systems WHY TECHS LOVE IT: - Fully offline — works in the shop, on the lot, or at a roadside service. - No ads, no tracking, no subscription traps. - Real citations on every answer so you can verify the source. - Completely free — every question, both mock exams, and the full reference library. No purchase, no account. - Clean UI designed for one-handed use on a phone next to the car. 100% FREE: Every practice question, both mock exams, and the full reference library are completely free — no in-app purchases, no subscription, no ads, no account. Practice questions are modeled on the Section 609 certification exam and the public 40 CFR Part 82 Subpart B regulations. This app is a study aid; certification is awarded by an EPA-approved 609 test administrator. Download EPA 609 Certification Prep and master the MVAC exam in your pocket.
Screenshots
Verdict
The clearest difference is rating: EPA 609 Certification Prep at 4.8 against IN HVAC Calculator's 4.1. EPA 609 Certification Prep also leads on update cadence (every 2 weeks vs every 6 months). IN HVAC Calculator's advantage is monetization model (free vs free with in-app purchases) and iOS requirement (12.0 vs 17.0). On price, ratings volume, ads and in-app purchases there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
EPA 609 Certification Prep holds the better App Store score, 4.8 against 4.1. Both are backed by a comparable volume of ratings — 10 and 4 respectively.
IN HVAC Calculator ships an update every 6 months, EPA 609 Certification Prep every 2 weeks. The most recent releases landed on November 2, 2026 and October 31, 2026 respectively.
| Parameter | IN HVAC Calculator | EPA 609 Certification Prep |
|---|---|---|
| Price | Free | Free |
| Rating | 4.1 (10 ratings) | 4.8 (4 ratings) — better |
| Number of ratings | 10 — better | 4 |
| Update frequency | Every 6 months | Every 2 weeks — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free — better | Free with in-app purchases |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 12.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 27 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | Gregory Enterprises | Shanghai Sheyuan Network Technology Co., Ltd. |
Customer experience
IN HVAC Calculator
EPA 609 Certification Prep
In-app purchases
IN HVAC Calculator
No in-app purchases
EPA 609 Certification Prep
No in-app purchases
Questions
Is IN HVAC Calculator free?
Is EPA 609 Certification Prep free?
Which has better reviews, IN HVAC Calculator or EPA 609 Certification Prep?
Do IN HVAC Calculator or EPA 609 Certification Prep have ads?
Which is updated more often, IN HVAC Calculator or EPA 609 Certification Prep?
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