One Trade, Whole System
Boiler, gas line and heating lines handled by one licensed trade rather than split between two.
Boiler Repair, Service & Installation In Gaithersburg, MD
Gas boiler repair, service and installation across Gaithersburg and Montgomery County — including hydronic and underfloor systems, from the licensed trade that also owns the gas line and the pipework.
4.9 from 2,979 Google reviews
30+ Years 30+ Years Serving Maryland
24/7 Service 24/7 Emergency Service
WSSC Licensed WSSC Licensed & Insured
Locally Owned Locally Owned and Operated
Heating Service in Gaithersburg
Boiler repair and installation in Gaithersburg
The heating half of Mallick Plumbing & Heating is gas boilers. A boiler burns natural gas to heat water or raise steam, and that heat travels through pipes to radiators, baseboard heaters, or tubing set beneath the floor.
We repair, service and install gas boilers across Gaithersburg and Montgomery County, including hydronic underfloor systems. It is the same licensed trade as the plumbing — the gas line, the water side and the heating lines are all one system.
Schedule Heating Service
Tell us what you need — we’ll be in touch fast.
Honest On Replacement
Age and repair history said plainly, so replacement is a recommendation you can check.
Cover When It Matters
Same-day and 24-hour emergency cover for the night it does fail.
Boiler noisy, cycling, or heating unevenly? February is a bad time to find out.
Call (301) 804-6759Worth Knowing
Why gas boilers suit these houses
Boilers heat evenly and quietly. There is no forced air, so heat arrives as steady warmth rather than in gusts, and it does not move dust around the house the way ducted systems do.
A gas boiler needs a suitable gas supply, venting and pipework. We assess the home and existing system before recommending equipment.
How the call runs
How a heating call runs
Installing a boiler is three trades at once: the boiler itself, the gas line feeding it, and the heating lines carrying water or steam through the house. Getting one of the three wrong is how a new boiler ends up underperforming a working old one.
That is the reason this sits with a licensed plumbing and gas contractor rather than a heating-only installer. We assess installations in the home, and financing is available through GreenSky on new boiler installation.
Which system is it
We establish whether the fault is the boiler, the gas supply or the heating lines — three different jobs that present the same way from the thermostat.
Repair or replace
The unit's age and repair history weighed openly, so repair-versus-replace is a decision based on condition and service history.
Sized and planned
Installations sized to the house and to the existing pipework, with in-home assessments and GreenSky financing available.
Commissioned and warrantied
Commissioned, tested and warrantied — one year on installations, thirty days on repairs.
Worth Knowing
Fix it in autumn, not in February
Heating faults are worth acting on early, and not for the usual reason. A boiler that is noisy, cycling or heating unevenly is telling you about a fault that is still small, and small faults become breakdowns on the coldest night of the year — which is exactly when every heating engineer in the county is already booked.
Same-day and emergency service are available. A planned service visit can help identify developing faults before cold weather.
Why Mallick
Maryland Has Trusted Mallick For 30+ Years
WSSC-licensed and insured crews, and warranties in writing: one year on installations, 30 days on repairs. The same standard whether it is a heating call at 2pm or a burst line at 2am.
Google reviews
2,979
4.9 average across Gaithersburg, Frederick and Woodbine
Ways To Save
Current Offers On This Job
$32
Off
Any Plumbing Service
$1 off for Each Year We’ve Been in Business!
Limit 1 offer per customer, cannot be combined with other offers, residential use only, must be presented at time of service. Not applicable to dispatch charge. Only applies for work performed. Valid Jan 1 – Dec 31, 2026.
Our maintenance plan
The Service Contract Of Choice
A 12-month annual maintenance contract for your home’s plumbing. The team is small enough to give you personalized attention and large enough to handle whatever comes up.
What stands behind every contract
12-month coverage term
24/7 emergency line
Licensed, trained technicians
Payment plans available
2-Year Extended Warranty for Furnished & Installed Equipment
6-Month Repair Warranty
Levels are matched to your home
The office confirms the current contract levels and details before you commit — call and the team will walk you through the options.
12-month term · Sign up by phone
Customer Field Notes
What Customers Remember After The Call
4.9
2,979 Google reviews across three Maryland locations
Field note 01 · Gaithersburg, MD
“Eric and Nick did a wonderful job.”
Very thorough and provided detailed explanation of what was needed to get our garbage disposal up and running.
Abbas and Koli were great technicians.
Quickly diagnosed the issue, thoroughly explained everything, and gave me a few options to move forward. I've had great experiences working with Mallick, highly recommend.
Chrissie Schenkel · Gaithersburg, MD Abbas came to our house for an emergency repair on a Saturday.
He was courteous and kind, he didn’t rush, and he worked hard to fix our problem and thoroughly investigate. It was hard to find a plumber who could do this on a Saturday at the last minute, and we appreciated Mallick’s and Abbas’s willingness.
Raj Nayak · Gaithersburg, MD Abbas Rahimiari was exceptionally professional, looking at our two plumbing problems, describing the underlying issues, fixing one immediately and explaining options on the other. Courteous, clear and efficient. And knowledgeable.
Gordon Schatz · Gaithersburg, MD I had a wonderful experience with Billy.
He was amazing and he was able to fix my issue with no concerns! 10/10! Thank you Billy.
Mia Barker · Gaithersburg, MD Excellent service and support from William Clem and Malick Plumbing.
Had a pinhole leak in a water service line. Found and fixed the problem … thanks so much.
Daryle Seckar · Gaithersburg, MD Roberto and Adelson were great to work with, efficient, and answered all questions. Top service and repair of water heater!
Jonathan Daly · Gaithersburg, MD
Fred and Luka were great!
They took the time to find the issue as well as helping me get opinions on future concerns as a new homeowner! Real experts and will work with them again!
Elijah Wadsworth · Woodbine, MD Abbas and Koli were fantastic.
They quickly identified and resolved our issue, and did a check to ensure there were no other sleeping issues. They were a pleasure to work with, respectful, and kind.
Kelley Barnaby · Gaithersburg, MD I received great service from both Ikem and CJ today.
They quickly identified the leak and fixed the issue. They also did a great job replacing some valves that needed replacing. They were very experienced and efficient. I have used Mallick several times and have always been pleased with their service.
Melissa Cavuto · Gaithersburg, MD Abbas and Erick were professional, knowledgeable and kind.
They inspected and guided me to make safe choices with my range that had a gas leak.
Andrea Huerta · Gaithersburg, MD Abbas and Bryan installed my new water heater.
There was a leak in my furnace and they fixed it also! The job was perfect. They had to install vents that were well done. They left no trace and the house was completely clean. The new water heater works like a charm. HIGHLY RECOMMEND this team and Mallick.
Janet · Gaithersburg, MD Kyle was so helpful in helping my husband and I fix the water pressure in our house. Kyle was very well versed and experienced, providing great options for future improvements to water filtering. I would highly recommend his services to anybody struggling with plumbing issues.
Azusena Herrera Tapia · Gaithersburg, MD
Every quote above comes directly from Mallick’s current Google Business Profile record.
Read more customer storiesCommon Questions
Heating Questions, Answered
Still Stuck?
Talk To A Plumber
(301) 804-6759Someone picks up 24/7 — nights, weekends, and holidays included.
What are the common signs my boiler needs repair?
Banging or whistling noises, heat that is inconsistent from room to room, water leaking around the unit, energy bills rising with no change in use, or the boiler switching on and off frequently. Any of those is worth an inspection while it is still small.
Is it better to repair or replace my boiler?
Age, condition and repair history guide the decision. We assess the boiler and explain whether a lasting repair is practical.
Do you install hydronic and underfloor systems?
Yes. Hydronic underfloor heating runs from the same boiler, using tubing beneath the floor rather than radiators. We install and service both, and can advise which suits a given room or extension.
Do you offer financing on a new boiler?
Yes. Financing is available through GreenSky for boiler installation. Contact us to discuss the available options.
Where We Work
Heating Service Across Maryland
Bethesda Rockville Silver Spring Germantown Potomac Olney Clarksburg Damascus Chevy Chase North Potomac Frederick Woodbine Columbia Ellicott City Aspen Hill Boyds Burtonsville Darnestown North Bethesda Poolesville Takoma Park Wheaton–Glenmont White Oak Green Valley Linganore Washington, DC College Park
Related Services
Plumbing Repair, replacement and installation across every plumbing system in the house — WSSC-licensed plumbers, warranties in writing, and 24/7 emergency service throughout Montgomery, Carroll, Howard and Frederick Counties and parts of NW Washington DC.
Gas Lines Natural gas line installation, repair and replacement in Gaithersburg and Montgomery County by WSSC-licensed gasfitters — permit and inspection pulled as part of the job, and suspected leaks dispatched 24/7.
Water Heaters Repair, replacement and installation for tank, tankless and hybrid water heaters, with WSSC-licensed technicians and 24/7 emergency service across Montgomery, Carroll, Howard and Frederick Counties and parts of NW Washington DC.