# HVAC Toolkit Ultimate — user reviews > 15 indexed App Store user reviews of HVAC Toolkit Ultimate by Carmel Software Corporation, rated 3.00/5 from 4 ratings. - Source: https://appshunter.io/ios/app/hvac-toolkit-ultimate/id391408247/reviews - App overview in markdown: https://appshunter.io/ios/app/hvac-toolkit-ultimate/id391408247.md - Rating breakdown: 5★ 1 · 4★ 1 · 3★ 0 · 2★ 1 · 1★ 1 ## Most critical reviews (10 lowest-rated) ### 1/5 — Not worth it *2019-04-17* I bought the app to do load calcs on my iPhone . There is something seriously wrong with that portion of the app however all the other parts work fine , only problem is I need a program to do quick load calcs not to find my superheat and subcool ### 1/5 — POS *2015-08-10* Not easy to use, very confusing, lacks basic explanations of input fields, can't remove information once it's entered, app automatically adjusts dimensions no matter how many times you put it back. "Support" is a joke. No way to get additional information on any of the fields. Total rip off. ### 1/5 — Update killed this app! *2015-03-10* Carmel better get busy fixing this. I paid way too much for an app that won't open!!! ### 1/5 — Nothing *2015-03-03* App will not load since last update. I used it all the time before. ### 1/5 — Update ruined the app *2015-02-20* Just updated to the newest version and now the app won't even load!?!? I worked up 3 load calculations yesterday and it worked great, after update NOTHING! ### 1/5 — Insanely overpriced!!! *2013-01-27* For the price we're paying, this app should have more features and must be more user-friendly. The app is even ugly. Everything this app does can be found for free elsewhere. Highly disappointing and the developers keep on adding the same apps over and over again instead of updating the existing ones just to cash in on more money. Apple should block such developers from entering the Apple Store. Bottom line... Don't buy this crap. ### 2/5 — Great app works great *2016-04-03* doesnt work. cant do any load calcs. input data and it disappears ### 2/5 — Disappointing *2011-12-17* Very disappointed in this overpriced app. Can't select door types other than French. Limited functionality. Needs major improvements and a price cut or their is no value here. I seriously doubt a load submitted with this program would be accepted by a knowledgable code official. ### 3/5 — Ultimate, isn't. *2012-09-08* Missing the one item I wanted; room by room heat load calcs. It has a room by room that has ceiling as the only opaque feature active. $24 more to get the residential load calc "plus". Bummed at the cost of the first, and further by the second. ### 4/5 — Decent App *2024-06-07* This app works well (especially given the cost) It has a few bugs when used with modern devices (notably the scrollboxes get clipped). ## Most praised reviews (5 highest-rated) ### 5/5 — Very useful app *2015-02-23* This app installed fine for me, and it’s great. Has everything I need for my HVAC work in the field including load calcs, duct sizing, and keeping track of my maintenance. Worth the price! ### 5/5 — Powerful and versatile HVAC app *2011-12-20* I've been using this app for a month, and it's been great for doing all my field-based HVAC work. I've used the Load Calc module the most (Manual J-based), and it works very well and is quite accurate. My customers are very impressed, too. It also has other modules like duct sizing, pipe sizing, psychrometrics, and more. Pretty much anything you need in an HVAC app. It is pricey for an app, but really, $50 is cheap for a powerful piece of software that helps me get more clients. The only request I have is you add a refrigerant charging functionality. That would make it perfect. ### 5/5 — Very useful *2011-07-28* I downloaded this app because it is an all-in-one HVAC app, including load calcs, ventilation, duct sizing, pipe sizing, steam tables, psychrometrics, and more. I was hesitant at first by the price, but I figured buying all of these apps individially would cost much more. I especially like the load calcs and I use those all of the time. ### 5/5 — Superb iPhone app *2011-01-16* This is one of the most useful HVAC apps I've seen and used. It really has all I can ask for from a mobile app including duct sizing, load calcs, pipe sizing, psychrometrics, and more. I like I can email lots of the results back to my office, too. I look forward to even more functionality being added. Great work. ### 5/5 — Awesome all-in-one HVAC app *2010-12-13* This really is a great HVAC app, even for the $49.99 price. It includes all the functionality you need out in the field for HVAC techs and engineers. I especially like the residential load calcs and the ventilation functions. Quite useful and I can email the results back to my office. Great work! --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-27.*