Delta T refers to the difference in temperature between two points in an HVAC system. It is denoted by the symbol “△T” and is commonly used by technicians to evaluate how effectively the system is heating or cooling. For example, in an air conditioning system, Delta T might measure the difference between the air entering the evaporator coil and the air leaving it. This helps assess system performance and diagnose potential issues.
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just left us a 5 star review
Awesome Work! Great Experience with Jonathan and Paradise Heating and Cooling Great experience from Jonathan and Christian! Job: Disassemble and remove old attic ductwork and install new ductwork and runs. Install Accuclean air filter in both attic and main floor systems. Install new smart thermostat and attic insulation infill. 1. Honest assessment of what is needed and more importantly, what is not needed. And not just trying to sell the most expensive option. 2. Competitive and reasonable quote. 3. I asked about radiant heat treatment as an add on, but he said while they could do it, it would not have efficient results and not worth the investment since I had a high hip roof and large attic area. 4. Great work ethic and work product. Duct system, filtering system and thermostat expertly installed, set up and running effectively. 5. All interactions cordial, efficient and polite. 6. Punctual in accordance with automated notices about arrival and appointment reminders 7. Clean work - brought coverings to reduce tracking of insulation through house areas traversed. Cleaned any evidence of insulation. 8. Works relatively quietly. No loud talk or music. 9. Small footprint on street. One van. I expected van and trailer. New materials brought in, unloaded and installed while old duct system all loaded up and removed. Very efficient. Overall, fantastic experience and is highly recommended.
Jonathan and the Paradise team are the best. In my 50 yrs of home ownership, I haven't had anyone I've trusted more. My wife and I downsized recently, and Jonathan helped us upgrade old to new heating & air units, including thermostats and attic insulation. Paradise Heating & Air is a great company... glad we found them years ago.
My unit was not working and they were working with my relatives. I asked if they would take a look at mine and they did with no problem. They told me what the problem was an within 2 days they had my unit up and running!
I had to leave another review for this company because we continue to be very impressed. Jonathan is an absolute pleasure to work with.
Awesome customer service. Exceeded my expectations compared to past experiences with different companies
Jonathon, as always, provided great service! He is very efficient and honest. Thanks Jonathon, Charles
Extremely nice, on time, helpful and explanatory. Very professional. Thank you
I was fortunately able to get an appointment for the next day. Jonathan & Austin were prompt and kept me advised of their arrival. They quickly found the problem with my "heat" and were able to fix it without problems. They were very friendly and professional, and I felt that their pricing was fair and reasonable. Thanks again, Guys! UPDATE: I once again had a very good visit from Paradise Heating & Air - they are very prompt and reliable and do an efficient job - thanks once again! I definitely recommend these nice guys!!!
Jonathan and the whole Paradise staff are professional, courteous, and fast. I had a system failure, and they were able to get to me quickly and diagnose the problem. Through Jonathan's research he discovered my system had a warrantied part needing replacement and saved me $1600. I would HIGHLY recommend Jonathan and the Paradise crew and will be using again!
Jonathan is highly technical, knowledgable, and efficient. I wish I had known his company years ago. I highly recommend Paradise for all heating and air needs.
Jonathan was very professional and knowledgeable, with a great personality. I will be doing business in the future with his company. I immediately signed up with the company’s annual service plan.
Paradise Heating and Air are the BEST in the area! They’re very responsive and adapted quickly to our needs. Highly Recommend!!
Great service with very neat job. Highly recommend.
First of all they are very courteous people. Secondly they gave me an appointment asap and was there right on time in which I was able to keep track of the arrival by text messages. They diagnosed the problem and it was resolved in less than 30mins. I am truly grateful for Paradise Heating and Air. Thank you for your service. Side note: they chose the best name for the company. I was in Paradise after the repair lol
Very professional and knowledgeable. No need to look over their shoulder. Very satisfied with their work.
Always on time, easy to communicate, finest quality of workmanship and character, affordable pricing. Highly recommended.
Jonathan did a great job. Highly recommended.
Honest and kind. Gave incredible price for work completed. Called and was able to come earlier than expected! Cannot recommend enough
Jonathan and his helper were awesome. Keeping us informed as to what they were doing as they replaced our heating and air units. They were pleasant to have around and did a great job. They not only left the areas clean they hauled off all the old equipment. We would highly recommended them to everyone.
These guys got the job done! Came in did not try to sell me a unit but fixed my existing unit and I appreciate them so much bc it was the hottest day of the year and my unit was completely out. I recommend 💯
Jonathan and team are hands down the best folks I have ever worked with in the home services industry. Reasonable prices, high quality work, great communication and responsiveness, 5 stars all around. Highly recommend.
5 stars! Look nowhere else for all of heating and cooling needs. Jonathan is amazing - experienced, reasonable and reliable. Look nowhere else!
Love their service. They are very prompt and courteous. They get any issues resolved immediately and are amazing to work with!
Great service, very professional! Highly recommend.
Johnathan was great! We had a moisture problem in our kitchen cabinets that were on an interior wall. He spent a good amount of time figuring out what was going on, gave us a solution and answered all of our questions. A very good experience!
I was extremely impressed with Paradise Air and am very glad I found them. I have a very old HVAC system they needed some ducts and a condensate pump replaced. They were extremely thorough and clearly explained everything they planned on doing. The price was excellent given how much work they had to do in the crawlspace and the extra time they spent with me advising me on how to get as much out of my old system as I could. They weren’t there to try to sell me a new system. They were there to repair what I asked them to at a reasonable price and help me extend the life of my current system. I won’t even think of calling anyone else from now on.
Paradise Heating and Air was great to work with—professional, on time, and very thorough. They communicated clearly throughout the entire process and were upfront about pricing and exactly what they discovered was wrong. I’m very pleased with their service and will definitely use them again. Being on time was a huge plus as well!
Amazing service and very helpful as well as willing to inform me of what was going on.
Great company to work with AGAIN! The minor issues found were carefully explained and resolved. We setup a biannual service plan to keep this 20 yr old house in tip top shape. This is the company you need to handle your HVAC needs.
I recently had this company come out to my home because my unit wasn’t working, they had someone out the same day. Jonathan was extremely professional and knowledgeable, definitely recommend this company!!
We recently bought a home and right away one of the AC units failed. Of course it was after hours (do AC units ever fail not after hours?). I called Paradise Heating and Air and they dispatched quickly, diagnosed the problem, and had us cool and running again before the kids were even in bed. Jonathan figured out the issue fast, and the quality of work and the cleanup afterward were truly noticeable. They've become our go-to HVAC company, always a notch above on service and workmanship. If you need emergency AC repair or any HVAC work in Vestavia Hills or anywhere in the Birmingham area, don't hesitate to reach out to this team. Love working with them!
Great service, price, and quality workmanship! Highly recommend! I will use them again.
Very prompt, respectful, thorough, and didn’t break the bank.
Jonathan was fantastic to work with! We had multiple quotes and opinions on some work we needed to get done and his recommendations and quote came in best and he had some recommendations others did not make that make us feel like he really cared about doing the right thing and really inspected our hvac situation. Jennifer and Gracie were also stellar! Will call them back and recommend to our friends!
Paradise was very responsive and was able to come same day. Very professional, nice and honest - would recommend to anyone!
Excellent service, on a Sunday, highly recommend :)
I called at the end of the workday on Friday when we arrived back home from a trip and the temp in our house was 114! We had, fast, fair service and were cooling off within the hour I had called. Excellent experience!
Being a first time customer I was extremely impressed with how punctual and professional the technicians are. I highly recommend Paradise Heating and Air
Paradise company is very reliable and trusted. Jonathan is very knowledgeable and understanding. He replaced A C Unit in my home and since then it's working efficiently. I want to recommend this company for everyone
Always on time and very well please explain everything that they did
Most honest, knowledgeable and affordable HAVC company I've ever dealt with.
Update: May 2026 Paradise came and serviced my business and home this week per the service agreement I asked them to sign me up for. Excellent trustworthy people and processes yields a top level result. You can trust them too. Call them and see what I mean. From the first phone call, I was impressed, I spoke to Jennifer and on a follow up call, I spoke to Gracie. Both are related to the owner Jonathan who came out today and gave me a breakdown and an idea of what is needed and proposed how to go about doing a mini split, which I’m excited to get done, so much so that I wanted to give a review, even before the work begins which I’m sure will be excellent. He recommended a good brand Mitsubishi and explained why he chooses them, giving a very detailed explanation. Jonathan was very personable and efficient and I look forward to the job being completed and future business with this company.
Great, fast and professional service always!!
They scheduled me in a timely manner. The technician (Jonathan)was very professional, explained the system, and answered all my questions.
Great service, assessed the issue in no time. Discussed all available options, extremely professional and friendly . Appreciated the help. Provided the best price .
Great service - always on time and very professional.
Fast on time & courteous
Wonderful
