My plumber recommended them to restore my hydronic system when a prior contractor couldn't restore my system after shutting it down for plumbing work. Basically, an entire zone wasn't getting any heat and the pump was running hot. Karalis' guy charged me a $135 diagnostic fee to tell me that either the system was air bound, or the pump was bad. I could've diagnosed that myself. He promised to get me an estimate on making changes to the system so that the problem would be resolved. After a few few weeks of not hearing from them, I called and got the owner on the phone. He said that they were looking into it and that they would get back to me with an estimate for the work. It is now been three months. Radio silence. I'm not impressed, I won't use them, and I recommend you don't either. read more

These guys were great! It's not easy to find an honest small company that works on commercial refrigeration anymore so they certainly are worth reaching out to. We recently had a compressor go down for a large walk in cooler and these guys stepped up with a no nonsense quote. They had us up and running in a couple of days. They were very professional. The owner took the time to go over the parts/repairs needed and answer all of my questions. The price was fair. Moving forward they also recommended a preventive maintenance service to keep the new compressor and other parts of the unit healthy and running strong. I can't speak for their AC and heating (yet!), but for refrigeration needs in the Delco area they are reliable and responsive. Thanks again guys! read more

During the recent heat wave, we grew concerned that maybe our AC unit wasn't performing as well as it should. I did a search in Yelp for highly rated AC technicians in my local area. Karalis had the best ratings, so I called them, and their service absolutely validated their ratings. They had a tech on hand the following day. He was polite and professional, and he did a quick and thorough evaluation of our system, made some recommendations on maintenance, and confirmed that the problem with our AC was just that is was so damn hot that the unit was struggling to keep up, but that it was functioning normally. The charge for the service was very reasonable. I would not hesitate to recommend them, and if or when the need arises, I will most definitely call them again. read more

Super responsive, reliable, polite. We have used them for since we moved in over 4 years. affordable and efficient. they have installed heating, hot water heaters, drain and investigated problems with boiler. They fix it the first time and stand by their work. Highly recommend read more

My air conditioning wasn't working and I needed to contract someone to come out and service the unit. I reached out to Karalis and I cannot say enough how well everything was handled. From the initial call to getting the work done, it was seamless! Team is very professional but most of all honest and transparent. I would highly recommend them to anyone. read more

We could not have been happier with our repairs by Karalis Mechanical. Paul was wonderful, and quickly repaired the heating unit on top of our science lab at our school. He was quick, efficient, and professional. We're obviously not looking forward to the next issue we have at school, but we're certainly looking forward to working with Paul and Karalis Mechanical Services in the future! read more

First & last time Customer. Called in light of other positive reviews. Our a/c was working but we noticed a small puddle of water at base of the furnace. Called for service & wanted a/c system checked out before the full summer season. Tech came out & said system a little low of refrigerant( less than 1lb). Tech never removed side panel of outside unit to examine & never measured temp of air being blown by the furnace. When I asked about checking for the leak he gave the impression why bother since unit is 15 years old. And the crowning moment was the bill for over $200. I paid by check & he said the office would email me a copy of the invoice since they had my email address. A week went by & nothing received. I called the office who confirmed my email & said they would send it. Guess what....never got it. Sent them an email from their website & still no response. There are plenty of other companies that would have a more thorough inspection & more reasonable price. read more

Paul was great! He came out right after a holiday and was professional as it gets. He was patient with all my questions and being over his shoulder. He even fixed a DIY fail that should keep my HVAC in tip top shape. I would highly recommend Karalis to anyone who needs help with their heating and cooling needs. read more

We've been using Karalis Mechanical Services for the past 15 years for all our electrical, heating and air conditioning services. The staff are intelligent, dedicated, honest and excellent pricing. They're truly an amazing company! Two weeks ago it was a major heat wave and our air conditioner broke. I've a Sear's Home Warranty and I was told our piece was on back order for weeks and no idea when they could even replace our unit. I immediately called Paul, who was on vacation. Not only did he get his staff immediately over to our home, the new unit was installed in less than 24 hours. We were speechless how quickly they were able to help us! Fair pricing and excellent service! A few months ago we needed a new water heater. Once again Karalis Mechanical Services helped us to select the correct one for our home and installed it. We've an older home and they've been able to guide us with our numerous electrical needs! They even installed a home generator for us...they really do it all! This company is off the charts with their knowledge and service. I honestly wouldn't trust another company for our air/heating and electrical needs after our great experiences with Karalis Mechanical Services! read more

Karalis Mechanical Services is great to work with. They get back to you promptly and have resolved the problem the same day. Reliable, responsive & friendly service. Couldn't have asked for better service. Will continue to use them for all our needs & recommend them. read more

Our heater broke on an eighteen degrees day. I was so thankful that Karalis Mechanical Services came out within three hours of my phone call and fixed the problem. I will definitely use them again in the future! read more

Great guy. Honest and dependable. Recently used him for AC / Heat service. Does a great job.

Outstanding service and very honest. Unlike most HVAC companies you can believe their analysis of you're problem. Very competent. Make this company your go to company for your HVAC needs. You will be glad you did. read more

Excellent service, fast and very reasonable pricing. He's excellent at explaining things and answered all questions I asked. Definitely my new Hvac guy. read more