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A B Chelini - United Service Specialists

Founded 1978 • With Angi since December 2004


(71) Verified Reviews


United Service Specialists has been servicing the Washington Metropolitan area for almost 40 years as A.B. Chelini. We have recently changed our name in a rebranding​ effort and will be adding more services to our commercial and residential departments over the next year! With United Service Specialists, you can always be assured of quality workmanship and attention to detail. With over 150 years of combined experience, we proudly combine state of the art service with cutting edge products and old-fashioned customer care. Many of our technicians have been part of the USS / Chelini family for over 20 years and help train our new technicians, facilitating continuous quality. We are constantly continuing our education through classes, certifications and licensing. We can service all brands of air conditioners, furnaces, heat pumps, boilers, geothermals, water heaters and other equipment providing reassurance that you will get the best options to meet your needs. What sets us apart is our attention to customer service. From setting up your appointments and the work performed to the warranty we stand behind we are committed to surpassing your expectations. ​We are pleased to offer a call ahead appointment time so you are not waiting for us to show up as well as maintenance agreements so WE can take care of your systems so you don't have to! With 24-hour emergency service, ​you are never without help....

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Verified Reviews

A few reviews for this pro…



I'm not sure where to even begin with my experience. It went downhill with one single contact Mr.Bill.(that's all I got for name of the owner) I've owned my home for 36 years... changed my HVAC system after 32 years and the new one had a part to replace. My Ex husband did the replacement of the system, so this is the first time I've had to make contact with anyone for repair. Needless to say I had...

Compressor replacement

CATEGORY heating & air conditioning/hvac



Horrible and grift like service. I used A.B. Chelini for many years and even after they changed to United Service Specialist. I had so so results but, I like to be loyal to local businesses. So I called them to replace the faucet on my kitchen sink. The same sink they had fixed less than a year ago. Anyway, I purchased a sink at HD and simply needed it installed. When I received the bill I was sho...

Sink Installation

CATEGORY heating & air conditioning/hvac,plumbing


Hi [Member Name Removed], Thank you for our original 5-star review that you sent to us for the work provided. Unfortunately, your one-star review is because you feel since you purchased your own kitchen faucet/sink you should pay only $115 for 2 hours worth of actual technician time. Your initial complaint was that although your invoice was correct monetarily your invoice said installed owner prov...


Awesome technician. Replaced part, cleaned coils, educated me on preventative maintenance and stayed to perform additional preventative maintenance so I could maximize my day off from work. I was able to get an appointment in one day.

HVAC - AC wasn't working.

CATEGORY heating & air conditioning/hvac



It went very smoothly and quickly. Alex was efficient, professional and courteous. It took two visits as the sink facet had to be ordered. They scheduled the appointments on the days and times we wanted (asap).

3 toilet upgrades, repairs. New kitchen sink faucet. Repair utility sink faucet.

CATEGORY plumbing



They're very good at anticipating problems and providing solution options.

Semi-annual HVAC maintenance

CATEGORY heating & air conditioning/hvac

Services Offered

Plumbing, Heating, Air Conditioning, Repairs, Service, Installation, Sales, Heat Pumps, Gas Furnaces, Geothermal, Humidifiers, Air Cleaners, Water Heaters, Boilers, Air Conditioners, Duct Fabrication & Repair, Baseboard Heating, Dehumidifiers, Electronic Air Filters & Cleaners, HEPA Air Cleaners, Faucets, Clogged Drain Lines, Running Water & Drips, Garbage Disposals, Radiant Floor Heating, Generators

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