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Jack Downing

Jack Downing

Senior Service Specialist

Rating

Reviews

LICENSES: GAS SERVICE

Having grown up in the family business, Jack officially entered the trades and joined the GSMS team seven years ago because it simply felt like the perfect fit. Guided by the Golden Rule, Jack appreciates the genuine kindness of both his colleagues and his clients, and he wants every customer to know that the team will always try to do their absolute best on every job. A natural learner who loves to master new skills, Jack stays incredibly active outside of work. You can usually find him renovating his first house, woodworking, playing the guitar and drums, or experimenting with new recipes on the grill and smoker. Depending on the season, he also loves skiing or cycling. Above all, he cherishes the time he spends with his fiancé, Hope, and their Australian Shepherd, Norman. Jack is also a proud member of the Pointer Fish & Game Club.

Name: Jack Downing

Recent Jobs and Reviews

Rated 5.0 out of 5 stars based on 192 customer reviews

Customers say: The overall sentiment across these reviews is overwhelmingly positive, reflecting high levels of customer satisfaction and appreciation. Customers consistently express enthusiasm about the quality of service they received, with recurring praise for professionalism, expertise, and efficiency. A dominant theme throughout is the technical skill and knowledge demonstrated by the service team, with many reviewers highlighting how thoroughly problems were diagnosed and resolved. The interpersonal qualities of the technicians emerge as another strong positive trend, with customers frequently describing them as friendly, personable, pleasant, and respectful. Communication stands out as a particularly valued aspect, with reviewers appreciating clear explanations, patience in answering questions, and being kept informed throughout the service process. Timeliness and punctuality are consistently mentioned as strengths, alongside respect for customers' property and maintaining clean, orderly work practices. Many customers express strong loyalty and trust in the company, with several indicating they are repeat customers or plan to continue using the service. The tone is enthusiastic and grateful, with multiple reviewers offering strong recommendations and expressing genuine happiness with the results. Overall, these reviews paint a picture of a service provider that excels in both technical competence and customer care, creating consistently positive experiences that foster long-term customer relationships.

At a glance

GSMS Air•Heating•Plumbing has completed 25 jobs between September 2026 and October 2026.

The 15 customer reviews shown here average 5.0 out of 5.

The most recent job was on October 8, 2026.

Recent work covers Merrimack, NH, Amherst, NH, Manchester, NH, Nashua, NH and Bedford, NH.

Job Locations and Reviews

Review
Jack came right on time and figured out my heating problem right away. He got me a new thermostat, installed it and the price was very fair for his time and the new thermostat.
BJ - Merrimack, NH 03054
Jack D.
Jack D. Checked in
Diagnosed a faulty upstairs thermostat that wouldn't turn the heat on. I repaced with a new one and made sure it worked. Thank you!
Merrimack, NH 03054
Jack D.
Jack D. Checked in
Look at ductwork in basement in regards to no air flow out of cieling supply grille. I found that the previous homeowner had taken the duct and connected it to the pellet furnace.
Amherst, NH 03031
Jack D.
Jack D. Checked in
Outdoor curve causing boiler to run at low setppint temp. Changed setting on boiler. All set, thank you.
Exeter, NH 03833
Jack D.
Jack D. Checked in
Change outdoor curve setting. And free up pulp that I believe was seized<br>
Merrimack, NH 03054
Jack D.
Jack D. Checked in
Bad water pressure sensor. Laars no longer supports this part and has no replacement available. We will try to find something that is an appropriate replacement.
Manchester, NH 03109
Jack D.
Jack D. Checked in
Oil boiler annual maintenance.
Merrimack, NH 03054
Furnace maintenance & light pilot on stove. I found a small gas leak by the furnace and repaired it.
Furnace maintenance & light pilot on stove. I found a small gas leak by the furnace and repaired it.
Jack D.
Jack D. Checked in
Furnace maintenance & light pilot on stove. I found a small gas leak by the furnace and repaired it.
Manchester, NH 03109
Jack D.
Jack D. Checked in
Replacement of your existing well tank. We will properly disconnect and remove the well tank and install a new standard 32-gallon well tank as a replacement unit. We will use a new tee fitting kit and connections to ensure reliability in the future.
Chester, NH 03036
Jack D.
Jack D. Checked in
Outdoor shower winterization. Shut off valves inside. Drain water. Fill with antifreeze.
Seabrook, NH 03874
Jack D.
Jack D. Checked in
Taco leak break installation.
Manchester, NH 03104
Jack D.
Jack D. Checked in
Vacuum sack was worn out and fouled in showroom mens visitor bathroom. Replaced with new. Flushed many times to ensure it is no longer leaking. Thank you.
Bedford, NH 03110
Furnace PM.
Furnace PM.
Jack D.
Jack D. Checked in
Furnace PM.
Amherst, NH 03031
Jack D.
Jack D. Checked in
Replacement of existing 40-gallon electric water heater. New tank will be installed and reconnected to plumbing system. Mixing valve, expansion tank, and vacuum breaker added to meet building code. New drain pan installed with an emergency water shut-off valve for future leak protection.
Manchester, NH 03104
Review
Showed up when scheduled and did a thorough inspection with diagnosis of two components in our furnace which would cause trouble down the road.
Ted - Amherst, NH 03031
Jack D.
Jack D. Checked in
Furnace PM. Reccomend replacing combustion motor and flame rod.
Amherst, NH 03031
Jack D.
Jack D. Checked in
Loose wire connection in pump.
Bow, NH 03304
Jack D.
Jack D. Checked in
Gas leak found at oven gas connector. Replace with new appliance connector.
Newbury, NH 03255
Boiler PM
Boiler PM
Jack D.
Jack D. Checked in
Boiler PM
Madbury, NH 03823
Jack D.
Jack D. Checked in
Oil Burner Maintenance.
Bedford, NH 03110
Bow, NH - I found the boiler pump to not be working due to air being stuck in the system. I purged the zones out and fixed a loose connection on the boiler pump. I also fixed the exposed wiring on the HW tank pump. I recommend replacing the boiler pump with a more reliable and robust pump. We have sent an estimate for that replacement. Thank you.
Jack D.
Jack D. Checked in
I found the boiler pump to not be working due to air being stuck in the system. I purged the zones out and fixed a loose connection on the boiler pump. I also fixed the exposed wiring on the HW tank pump. I recommend replacing the boiler pump with a more reliable and robust pump. We have sent an estimate for that replacement. Thank you.
Bow, NH 03304
Replace tubspout that had a faulty diverter. Seal around fixtures with sealant. Complete a furnace maintenance. The blower motor was stuck on because of a faulty control board. I located one and replaced it today. Thank you!
Replace tubspout that had a faulty diverter. Seal around fixtures with sealant. Complete a furnace maintenance. The blower motor was stuck on because of a faulty control board. I located one and replaced it today. Thank you!
Jack D.
Jack D. Checked in
Replace tubspout that had a faulty diverter. Seal around fixtures with sealant. Complete a furnace maintenance. The blower motor was stuck on because of a faulty control board. I located one and replaced it today. Thank you!
Hooksett, NH 03106
Review
Jack was knowledgeable and personable
Janeen - Londonderry, NH 03053
Review
Excellent and professional service
Shawn - Gilmanton, NH 03237
Jack D.
Jack D. Checked in
Found minisplit system to be low on refrigerant. I went around and checked every connection with electronic detector and could not find anything. Confirmed with local distributor that this year of unit did have bad indoor coils. We will provide an estimate to replace them under warranty.
Gilmanton, NH 03237
Jack D.
Jack D. Checked in
2 new bath exhauaat fan + light combo replacement. Replace straight stop valve under vanity.
Nashua, NH 03060
Furnace PM. Replace leaking basket strainer.
Furnace PM. Replace leaking basket strainer.
Jack D.
Jack D. Checked in
Furnace PM. Replace leaking basket strainer.
Merrimack, NH 03054
Nashua, NH - Replace exhaust fan in reception. Repair broken PVC vent in reception ceiling. Begin installation of mechanic bathroom exhaust fan. Come back and do water heater.
Jack D.
Jack D. Checked in
Replace exhaust fan in reception. Repair broken PVC vent in reception ceiling. Begin installation of mechanic bathroom exhaust fan. Come back and do water heater.
Nashua, NH 03064
Jack D.
Jack D. Checked in
Rinnai no HW. Found inlet screen completely plugged. Still producing lukewarm water so I completed a flush on the HX. Hot water back on. Thank you! I reccomend testing water and adding a sediment filter to your home water. This was very premature for the system to be blocked up.
Amherst, NH 03031
Review
Excellent service
Gary - Stratham, NH 03885
Review
Jack was very professional, courteous, personable and thorough. Definitely at the top of my list for any future work needed and routine maintenance.
Bob - Manchester, NH 03104
Review
Jack did a great job checking our mini split and explaining how it should operate. He took the time to answer all our questions.
Joe - Nashua, NH 03060
Review
Jack was thorough and answered all questions. He’ll be our requested service tech from now on
Len - Newmarket, NH 03857
Review
It is always great to see Jack! GSMS never disappoints.
Karen - Nashua, NH 03063
Review
very courteous, efficient. a pleasure to work with.
Peter - Merrimack, NH 03054
Review
Excellent as usual
John - Hollis, NH 03049
Review
Great service, right on time. Jack did a great job picking out my new faucets.
Lisa - Merrimack, NH 03054
Review
Excellent service, hard working individual, arrived on time
Kathleen - Merrimack, NH 03054
Review
Jack really took care of me and my home today. Not only did he repair a broken system but when I mentioned my AC wasn’t working correctly, he thought to bring a backup panel so when he saw that was the issue, he fixed it right then and there….no “next visit” needed! I could go on but let me just say how well taken care of I feel. Thanks to the whole team but especially Jack today!
Amy - Moultonborough, NH 03254
Review
Worked with Jack before. He is always professional & does what he has to do to remedy our problem. He’s a great guy & the company should be proud of him.
Steve - Nashua, NH 03064
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