HVAC System Replacement & Service in Gaithersburg, MD & DC

Reliable HVAC Services for Maryland, Virginia & Washington DC

Delivering Expert Repair, Installation, Maintenance and Replacements Since 1994

Driven by Experience, Committed to Excellence

With a legacy of excellence and innovation set by Mallick Plumbing & Heating (MPH) and Mallick Mechanical Contractors (MMC), Mallick Mechanical Services (MMS) was founded by industry veterans, drawing on over 80 years of experience to specialize in HVAC service, system replacements, and preventative maintenance for both residential and commercial customers. Today, MMS joins MPH in upholding the trusted Mallick name—delivering exceptional service, advanced solutions, and a commitment to lasting relationships.

Tailored HVAC Services for Residential & Commercial Customers

Residential Service

Learn More

HVAC Service

Heating

Air Conditioning

Indoor Air Quality

HVAC System Installation

HVAC Preventive Maintenance

Commercial Service

Learn More

HVAC Service

Preventive Maintenance

Equipment Installation

Equipment Replacement

System Analysis & Reporting

Mechanical Room Redesigns

Small Projects

Tenant Fit-Outs

Mallick Mechanical Services

4.8

Based on 11 reviews

review us on

S M

19:02 02 Jul 25

Great work. Our AC went out. A tech was there that morning, we had loaner window AC units that afternoon. System replaced within a week. Very happy with the process. We were able to finance the new system with deferred interest too. Very pleased with the communicationa in service.

Thom Byrnes

21:44 24 Jun 25

Mallick installed a Mitsubishi Ductless split heat pump system in my old log house – unit was properly sized and installation went faster than expected considering the 3″ hole that had to be cut through a 150 year old oak log for the line set. Management and installation crew were courteous and professional at all times – a true 5 star experience!

Matthew Fischer

16:49 24 Jun 25

Our family needed to replace our old HVAC unit. Mallick Mechanical Services responded right away and were able to replace our HVAC unit. The tech that came out was very helpful and knowledgeable about HVAC to help us understand how to maintain our HVAC system to ensure it stays in good shape. We even signed up for a preventative maintenance agreement so Mallick Mechanical Services will ensure everything is running smoothly for years to come. Highly recommend and will definitely use Mallick Mechanical Services again in the future

T P

20:35 23 Jun 25

Great response, great service. A/C thermostat went out and Tyler found the problem, corrected it and am enjoying the results of his efforts. Recommend Mallick for any service that is needed.

Jason Fowler

23:32 23 May 25

Mallick Mechanical Services provided me and my wife timely, professional, and cost effective services when our furnace wouldn’t light.

They were able to almost immediately diagnose the problem and then walked me through several options for repair and replacement. As a new home owner, it was incredibly helpful and comforting to hear the different options, pros and cons, and costs. We ended up needing a simple, low cost pressure switch replacement. Not only were they able to fix the issue quickly, no one attempted to upsell me on a new unit or upgrades to my system.

Response from the owner 15:24 29 May 25

Thank you so much for your thoughtful review, Jason! We’re glad we could help you and your wife get the heat back on quickly and cost-effectively. It means a lot to us that you felt supported and informed throughout the process—especially as a new homeowner. Our team always aims to provide honest recommendations, and we’re glad that came through in your experience. If you ever need anything in the future, we’re here to help!

Kim Coleman

17:28 22 May 25

We hired Mallick Mechanical Services to come out to repair a water leak on the lower level of our home and replace piping and some valves. The complexity of this was that the leak was directly over our electrical panel. While the scale of the project was smaller than that of which Mallick Mechanical normally does, they willingly sent Mike, their technician out to help us. Mike was professional, knowledgeable and fast. In addition to performing the repairs, he was also able to change out some of the shut off valves, making it much easier for us to access. I would definitely recommend MMS to anyone needing residential or commercial HVAC services.

Response from the owner 14:11 23 May 25

Thank you so much for taking the time to share your experience, Kim! We’re glad we could help, and we truly appreciate your trust—especially with the added complexity of the leak being above your electrical panel. Mike will be happy to hear your kind words; he takes a lot of pride in the service he provides to customers. Your recommendation means a lot to us, and we’re here whenever you need us—residential or commercial.

D Pascha

18:33 02 Feb 24

Hi all
Technicians Naun Gomez and Mr. Ian came out to assess the plumbing issues I had. The pipe pressure was way higher than it should have been. I also needed a new hot water heater and other work performed. They were timely, professional and very knowledgeable. My neighbor next door pipes actually burst. I am so grateful for Ian and Naun. Great service! I would recommend them highly!
D.L.

Response from the owner 11:10 22 May 25

Thank you so much for the 5-Star Review and kind words! We appreciate your recommendation and look forward to serving you again in the future.

Stacy Bowe

18:34 14 Jul 23

Luis and Ethan assessed the situation, diagnosed it and were able to make repairs immediately to a pinhole leak in a copper pipe that was causing a lot of damage.

Response from the owner 11:09 22 May 25

We appreciate the kind feedback, Stacy! We’re here and ready to serve should you need any future assistance.

Wilson Blanco

15:57 18 Aug 21

Response from the owner 11:09 22 May 25

Thank you for your feedback, Wilson. We appreciate you taking the time to share your experience with our team.

Daniel Shankle

11:00 30 Jul 21

Best job ever

Response from the owner 11:08 22 May 25

We appreciate the 5-Star Review, Daniel!

Call Now

Why Mallick Mechanical Services?

Service: We don’t just meet expectations—we exceed them. Your success is our priority.
Integrity: Honesty and accountability are at the heart of everything we do.
Respect: Treating others the way we’d like to be treated is not just a principle—it’s a practice.
Improvement: We never stop learning, growing, and evolving to better serve our clients.

Learn More

Reliable HVAC Services for Maryland, Virginia & Washington DC

Driven by Experience, Committed to Excellence

Why Mallick Mechanical Services?

We're Here to Help!