
Ductless mini split systems complete installation and repair., Central air conditioning complete installation and repair., Water heater replacement and repair. , and 2 more
"Andrew did a great job installing a tankless water heater. Hones and quality work. Great experience!"
Perla R. in March 2023

Furnaces, Boilers, central & ductless A/C & Heat Pumps, Gas Fireplace., Experienced HVAC installer and Service Tech. EPA Cert # 0352207329800., Electrical wiring and repairs; all work underwritten as required by code. , and 2 more
"Pat gave me a great deal on a high performance boiler as a replacement for my 20 plus year old boiler. He installed the boiler and an indirect water heating system in the summer and he had to follow up in the fall to make sure the heater worked correctly. He did that and was very responsive to my questions while at my home and over the phone later. Pat was very professional and knowledgeable and I would use him him again and recommend him to others. Bottom line - Pat did what he said he would do!"
Joseph C. in October 2009

Geothermal Heating and Cooloing, HVAC
"Great company. I had my AC fixed. Their staff, from April who handles admin, to Wayne who diagnosed our machine and found the leak for the cost of the initial visit whereas other companies wanting to charge us a $1000 to do that. To Thomas, who did a professional job, making sure I was informed of the process, answering any questions I had, and taking care of any concerns. He was professional and very personable. I can't say how much they cost compared to other contractors but right off the bat they saved me $1000 which puts them far ahead of the crowd in my book. Even if it was a bit of a premium, its a premium I am happy to pay for good craftsmanship and piece of mind."
6D1D356AE65C9B05447D86BA307AE43BDC1BD4E5807F79D2A35FFF57D63B30CC D. in May 2026
In business since 1980
About us: "In 1972, Donnelly’s Cooling, Heating & Plumbing began serving Pennsylvania residents with premier plumbing services and later expanded to add their superior HVAC services. As the area’s top choice for plumbing, heating, and cooling service, we’re proud to offer unmatched professionalism and quality results. With same-day and emergency services, our team is always available for your home service needs. Plus, with service for all brands and free estimates, you can trust you’re in excellent hands with our team."

Sewer & Water Line Replacement - We Can Repair or Replace a Water or Sewer Line Without Destroying Your Front Lawn - Call for a Free Water or Sewer Line Inspection, Plumbing - Water Heaters, Leaky Faucets, Running Toilets, Sump Pump Repair & Installation & Much More, Heating - We Service All Makes & Models, 2 Year Warranty on Repairs, Annual Service Plans for Cleaning & Maintaining Equipment , and 2 more
"After signing up with Servicepro, I was on the phone with Horizon within 10 minutes. This was about 9:30 PM. They offered to come and fix the problem he next morning (day before Thanksgiving) but I declined because I was going away. Anyway I scheduled a 10 am appointment for Friday November 28, 2008 and they were very prompt. The techinitian expalined the issue and my heat was up and running within the hour. Very impressed with their service and professionalism. I am now signed up for annual check up for my HVAC system and would not hesitate to recommend them to others."
kirk A. in December 2008

Plumbing, Electric Installations, HVAC Installations , and 2 more
"I should have written this review a year ago when the work was done. I needed a new heater. A neighbor recommended Marshall Services. I have found them to be a knowledgeable, family-owned team that truly stands out. They’re remarkably adaptable to change—adjusting plans smoothly when new needs arise—and their communication is excellent: clear, proactive, and easy to understand. From the first conversation, their honesty and transparency inspired my confidence, and every interaction since then reinforced that trust. Most importantly, you can count on them. They follow through on commitments, keep you updated without asking, and deliver quality work with genuine care. The combination of expertise, reliable service, and that family-owned touch made the entire experience seamless and stress-free. Marshall Services is my go-to HVAC company and has my highest recommendation."
3E501AEB98CC34BC356F259DE7649D52FDFEF0D5D357D4626A81A19BC3D89858 E. in May 2026
Colmar Heating & Furnace Contractors are rated 4.9 out of 5 based on 1588 reviews of 1588 pros.
The HomeAdvisor Community Rating is an overall rating based on verified reviews and feedback from our community of homeowners that have been connected with service professionals. See individual business pages for full, detailed reviews.
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