
Serving Glen Arm, MD and surrounding areas
Approved
In business since 2006
Free estimates
Emergency services offered
"Awesome job on fixing my AC unit!"





+5


Serving Glen Arm, MD and surrounding areas
Approved
In business since 2006
Free estimates
Emergency services offered
"Awesome job on fixing my AC unit!"





+5

Serving Glen Arm, MD and surrounding areas
Approved
In business since 2013
Free estimates
Warranties offered
"Genuinely honest, technically competent, and a penchant for pragmatic solutioning are the best ways I can describe Aaron and Blessed Cooling and Heating. They are at the top of our list for any future HVAC work."

Serving Glen Arm, MD and surrounding areas
Approved
Super Service Award Winner
In business since 1986
Emergency services offered
Warranties offered
"Showed up late, didn't install the bathroom fan as the manufacturer recommended (pic, fan5), dented the fan grille (pic, fan1). It was installed without the supplied support rails because he claimed he couldn't get in the attic. Now sure how I got the photos, then... The vent hose was kinked in the attic and hardly any air came out of the soffit, so I had to go into the attic to correct it. That's when I took the photos. Didn't give a price up front because apparently a bath fan with bluetooth speakers isn't in whatever book they price from. Not in the book? Overcharge. Generally very unhappy with the whole experience and will be looking elsewhere in the future. Not sure how when the customer supplies EVERYTHING but a romex clamp someone can charge so much. Absolutely unacceptable. $465 to have someone dent my fan, install it incorrectly, and throw out the parts that weren't used. Like the battery to the manufacturer supplied remote and the joist supports. I'm leaving the cost of service as originally quoted because it was only lowered to $465 after I complained about being ripped off."





+17

Serving Glen Arm, MD and surrounding areas
Approved
Super Service Award Winner
In business since 2000
Free estimates
Emergency services offered
"My air conditioning stopped working last night. I called Carroll mech . They responded immediately and sent technician to the house few hours later. Jordan Scott was very professional. He checked the system carefully and fix the issue soon. Really appreciate the service!"



Serving Glen Arm, MD and surrounding areas
Approved (Corporate)
In business since 1945
Free estimates
Emergency services offered
"Arrived on time , very detailed on a very difficult install . The installation team checked all the boxes, I highly recommend this company for air-conditioning services."


Serving Glen Arm, MD and surrounding areas
Approved
Super Service Award Winner
In business since 2000
Free estimates
Warranties offered
"The project (HVAC replacement) was completed on time and on budget. I particularly appreciated the time and patience provided in answering my questions related to the quote and options."



Serving Glen Arm, MD and surrounding areas
Approved
In business since 1989
Free estimates
Emergency services offered
"Technician was prompt, competent, and professional. In addition to the service rendered which was to repair my air conditioner unit, I signed up for an annual service agreement with Horizon."





+27

Serving Glen Arm, MD and surrounding areas
Approved (Corporate)
In business since 1982
Free estimates
Emergency services offered
"The technician who serviced our furnace did an excellent job. He is knowledgeable, efficient, and courteous. We welcome him to attend to our heating and air conditioning needs at any time."

Serving Glen Arm, MD and surrounding areas
Approved
In business since 1982
Warranties offered
Credit card accepted
We are a locally owned and operated company that values honesty and integrity in all aspects of our business. Our major focus is on the quality our work and producing outstanding results. We are committed to creating a level of value unmatched by any of our competitors. We look forward to building lasting relationships with our clients and guarantee your satisfaction!





+6

Serving Glen Arm, MD and surrounding areas
Approved
In business since 2004
Free estimates
Emergency services offered
"In 2012, Supreme Air installed a geothermal heat-pump system for our
1950s-era house to replace the oil heating that it had. They put
together a full package with several line item choices, handled the
removal of the old system and oil tank, and installed the new system
professionally. The system works well and saves money over the old oil unit.
However, the house had low humidity so then we had them add a humidifier. The first humidifier had issues, and the next didn't keep the humidity in the house up high enough. They were very professional and fixed/replaced the humidifiers multiple times without charging more money until we were finally satisfied that it was working properly and sufficient for our house.
Supreme Air has been very helpful and professional, and now the temperature and humidity in our house is probably as comfortable as we can get it.
"
Most professional HVAC technicians require two to three hours to complete an expansion valve replacement. The timeframe depends on your unit's accessibility and whether additional repairs are needed. The process involves recovering refrigerant, removing the old valve, installing the new component, and recharging the system. Scheduling during less busy seasons may result in more convenient appointment times.
Operating your air conditioner with a malfunctioning expansion valve isn't advisable. Continuing to run the system could potentially damage other components, particularly your compressor, which is significantly more expensive to replace. If you notice performance issues like inconsistent cooling or unusual noises, it's best to have your system inspected before continuing regular use.
Expansion valves don't have a standard replacement schedule, as their longevity depends on system usage, maintenance frequency, and environmental factors. Regular professional maintenance helps identify potential valve issues before they cause system failure. Having your HVAC system serviced annually allows technicians to monitor component condition and recommend preventative replacements when necessary.
Refrigerant leaks require prompt professional attention. If your expansion valve is leaking, you'll likely notice reduced cooling performance and possibly hear hissing sounds near the unit. Addressing leaks quickly prevents further system inefficiency and avoids the environmental impact of released refrigerant. Your HVAC technician will need to repair the leak and recharge the system with the proper refrigerant type and amount.
Because many AC issues present similar symptoms, professional diagnosis is recommended. Problems like inadequate cooling, inconsistent temperatures, or strange noises could indicate expansion valve issues, but might also stem from refrigerant leaks, electrical problems, or airflow restrictions. A qualified HVAC technician has the tools and expertise to accurately identify the root cause and recommend appropriate repairs.
From average costs to expert advice, get all the answers you need to get your job done.

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