Comparison

Ref Tools vs Unit Converter HVAC

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Ref Tools

This app provides HVACR technicians with essential tools and information for field service. It includes refrigerant calculators, troubleshooting guides, product finders, and access to spare parts. Listen to educational podcasts to enhance your knowledge on the go.

Highlights
  • Refrigerant Slider for P/T calculations
  • Solenoid valve coil testing tool
  • Refrigeration system troubleshooting guide
  • Product data finder
  • Spare parts ordering
  • Low-GWP refrigerant comparison
  • TXV Superheat optimization
  • Educational podcasts
Features
Read full description

Get the guidance, support, information, and tools you need—on the job and in the field. Ref Tools is a free, powerful app that contains essential tools every HVACR technician needs in their digital toolbelt. Ref Tools offers a collection of useful air conditioning and refrigeration tools: Refrigerant Slider As a featured part of Ref Tools, you get all the features and functionality that made Refrigerant Slider a hit with millions of installers around the world. Quickly calculate pressure/temperature ratios and find essential information on over 80 refrigerants. Magnetic Tool Test and troubleshoot solenoid valve coils quickly and easily. Troubleshooter Get help diagnosing issues in refrigeration systems, so you can quickly identify symptoms and find recommended solutions. Product Finder Find extensive product-related data in one place. Search by product code number or product category to access and share product specifications, documentation, visuals, and more. Spare Parts Access and order an extensive list of Danfoss spare parts and service kits for air conditioning and refrigeration applications. Low-GWP Tool Find and compare climate-friendly refrigerants for retrofitting by checking compatibility with the TXV. TXV Superheat Tuner Optimize superheat in less than 15 minutes. Using advanced algorithms, TXV Superheat Tuner provides valve-specific adjustment recommendations. Podcasts The workday can be full and the road long, so Ref Tools also provides you with some educational entertainment. You can listen to podcasts, including the popular Chilling with Jens podcast, directly in the app. So, take a break and chill out a bit while learning something new about refrigeration. More about Refrigerant Slider Refrigerant Slider, now a part of Ref Tools, helps you quickly calculate the pressure-to-temperature ratio for more than 80 refrigerants, including natural refrigerants such as ammonia and transcritical CO2. Refrigerant Slider also provides you with information about each refrigerant, including Global Warming Potential (GWP) and Ozone Depleting Potential (ODP). You can switch between the IPCC AR4 and AR5 values, where AR4 values are used in relation to the European F-Gas regulations. Refrigerant Slider’s P/T calculations use extended curve–fitting models based on Refprop 10 results. You can also see both dew and bubble point for refrigerants with glide. Streamline your workflow Ref Tools goes beyond just providing quick access to helpful tools; it helps you save time by allowing you to track your most visited service sites and save unique settings for each one. Simplify each service call with ease. Feedback Your input matters – we would love to hear it from you. We're committed to continuously improving Ref Tools to meet your needs. If you encounter a bug or have a feature suggestion, please use the in-app feedback function available in Settings. Alternatively, you can reach us via email at coolapp@danfoss.com. Danfoss Climate Solutions At Danfoss Climate Solutions, we engineer energy-efficient solutions to help the world get more out of less. Our innovative products and solutions enable a decarbonized, digital, and more sustainable tomorrow, and our technology supports a cost-efficient transition to renewable energy sources. With a strong foundation in quality, people, and the climate, we drive the energy, refrigerant, and food system transitions needed to achieve climate goals. Read more about us at www.danfoss.com. Terms and Conditions apply for use of the app.

About

Unit Converter HVAC

Features
Read full description

HVAC Unit Converter Pro helps HVAC technicians, engineers, refrigeration mechanics, and contractors convert between units instantly. Convert between all common air conditioning and refrigeration units instantly across 8 categories and 40+ unit types - eliminating calculation errors on job sites. 8 CONVERSION CATEGORIES: Temperature - °F, °C, K, °R (Rankine) for climate zones and equipment specs Pressure - PSI, kPa, bar, in. Hg, mm Hg, atm, Pa, in. w.c. (static pressure), microns (vacuum) for gauges and evacuation Energy & Heat - BTU, kJ, kcal, Wh, therm for load calculations Airflow (CFM) - CFM, L/s, m³/h, m³/s, m³/min for ductwork and ventilation Length & Duct - in, ft, mm, cm, m for duct sizing and pipe runs Area Calculations - ft², m², in² for room dimensions and surface area Volume & Capacity - gal, L, ft³, m³ for tank and system volumes Power & Output - BTU/h, W, kW, ton (refrigeration), hp, kcal/h for equipment ratings SMART FEATURES: Instant Conversion - Results update as you type, no button press needed Bidirectional Conversion - One tap to reverse conversion direction instantly Swap Units - Toggle between any unit pair in the same category Works 100% Offline - Field calculations without internet connection Accuracy Verified - Professional-grade precision for system design English & Spanish Support - Bilingual interface for diverse teams WHY HVAC PROFESSIONALS USE THIS APP: Eliminates manual conversion errors that cause mistakes Faster unit calculations than reference tables and charts Cross-checks between imperial and metric systems instantly Prevents equipment sizing errors from unit mistakes Works on every job site without cellular connection Dark theme prevents eye strain during outdoor work CONVERSION EXAMPLES HVAC TECHS USE DAILY: PSI to kPa for pressure readings on gauge conversions BTU to kW for international equipment specifications CFM to m³/s for ductwork design in metric regions °F to °C for climate zone design temperature conversions Tons to kW for heat pump capacity documentation BTU/h to watts for electrical load calculations PERFECT FOR: HVAC technicians on air conditioning service calls HVAC field technicians calculating refrigeration requirements Refrigeration mechanics sizing refrigerant lines AC contractors preparing equipment specifications HVAC design engineers in international projects HVAC apprentices learning unit conversions Building maintenance engineers managing equipment Commercial HVAC system commissioning work A tool trusted by HVAC technician teams nationwide. Part of HVACTools Suite - the complete HVAC technician and refrigeration calculator app collection for field diagnostics and system design. OPTIONAL PRO UPGRADE — $2.99 ONE-TIME IN-APP PURCHASE The following features require a separate one-time in-app purchase. They are not required to use the calculator: • Unlimited saved calculation history • PDF export of results • Dark theme • Ad-free experience

Screenshots

Ref Tools4 screens
Unit Converter HVAC4 screens

Verdict

The call

The clearest difference is price: Ref Tools at Free against Unit Converter HVAC's $0.99. Ref Tools also leads on in-app purchases (none vs 1). Unit Converter HVAC's advantage is iOS requirement (13.0 vs 15.0). On update cadence, ads and device support 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

CostPrice · In-app purchases · Ads · Monetization

Ref Tools is free to download; Unit Converter HVAC costs $0.99 up front. Unit Converter HVAC sells 1 one-off in-app purchase. Ref Tools asks for nothing beyond the download.

UpkeepUpdate frequency

Ref Tools ships an update every 5 weeks, Unit Converter HVAC every 3 weeks. The most recent releases landed on October 17, 2026 and October 18, 2026 respectively.

Scorecard3 real differences · 7 level
Ref Tools versus Unit Converter HVAC: the parameters behind the verdict, then further details
ParameterRef ToolsUnit Converter HVAC
PriceFree — better$0.99
Rating3.9 (52 ratings) — better—
Positive reviews57.6% of reviews—
Number of ratings52 — better—
Update frequencyEvery 5 weeksEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size98 MB34 MB
Age rating4+17+
DeveloperDanfoss A/SRizvan Adzhoian

Bugs and requests

Ref Tools

Reported bugs

27 issues
  • CRASHED instantly on Mac Mini M4
  • App won’t open on iPhone
  • App flashes up and disappears
  • Cannot open app
  • Immediately shuts off since recent release
Show 22 more
  • Crash au lancement since update
  • Will not save to Home Screen
  • Incorrect PT Charting for r134a
  • Information doesn’t slide down
  • Crashes on iOS12.1.4
  • App won’t open since previous update
  • List of refrigerants shifted upwards on iPhone 10
  • Stuck on R134a, needs update for current iOS
  • R744A only goes to 60 psi
  • Scale did not go low enough for deep vacuum
  • Missing R22 on Apple version
  • Missing R717 (Ammonia)
  • Missing R-22
  • Missing R124a
  • No longer lists Ammonia
  • Missing Refrigerants since app update
  • Missing Ammonia and CO2
  • r410a is missing since update
  • Removed r22, 410a, and 407c
  • Refrigerants missing now
  • Removed slider for ammonia
  • Scale doesn't go into vacuum

Requested features

18 requests
  • More residential AC information
  • Troubleshooter for Residential & Commercial
  • Add SP22 refrigerant
  • Add R-11 refrigerant
  • Add R-123 range down to 40 degrees
Show 13 more
  • Add R744 and R744A to 0 psia
  • Scale to go lower for R-123 vacuum
  • Add R410a
  • Add R407c
  • Add R404A
  • Add R22
  • Add R124a
  • Add Ammonia
  • Add CO2
  • Add R717 (Ammonia)
  • Scale going higher on CO2
  • Setting for high altitude
  • Scale to go into vacuum

Unit Converter HVAC

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Ref Tools

No in-app purchases

1 purchases

Unit Converter HVAC

One-time1
  • Pro Unlock$2.99

Questions

Is Ref Tools free?
Ref Tools is free to download, with no in-app purchases.
Is Unit Converter HVAC free?
Unit Converter HVAC costs $0.99, and also offers in-app purchases.
Do Ref Tools or Unit Converter HVAC have ads?
Neither Ref Tools nor Unit Converter HVAC shows ads.
Which is updated more often, Ref Tools or Unit Converter HVAC?
Ref Tools ships an update every 5 weeks, and Unit Converter HVAC every 3 weeks. Most recently, Ref Tools was updated on October 17, 2026 and Unit Converter HVAC on October 18, 2026.

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