
Serving Parkville, MD and surrounding areas
Approved
In business since 2006
Free estimates
Emergency services offered
"Changed the brand of heat pump to be installed 24 hours before installation with no prior notice."





+5


Serving Parkville, MD and surrounding areas
Approved
In business since 2006
Free estimates
Emergency services offered
"Changed the brand of heat pump to be installed 24 hours before installation with no prior notice."





+5

Serving Parkville, 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 Parkville, MD and surrounding areas
Approved
In business since 2010
Free estimates
Emergency services offered
"John Norwood knows his craft in the quality of his work. Years of experience and knowledge counts in the HVAC industry."





+7

Serving Parkville, MD and surrounding areas
Approved
In business since 2020
Free estimates
Warranties offered
"I had a great experience with this HVAC company! They were professional, arrived on time, and quickly diagnosed the issue with my air conditioning unit. They explained the repair clearly, completed the work efficiently, and had my AC running perfectly again. The technician was courteous, knowledgeable, and took the time to answer all of my questions. I really appreciated the honest service and fair pricing. I highly recommend them to anyone looking for reliable HVAC service!"





+5

Serving Parkville, MD and surrounding areas
Approved
In business since 2008
Free estimates
Emergency services offered
"I called Pohlman to replace my Gas water heater. I was very pleased with their service. They were very professional, came out on the same day, took the old tank with them and cleaned up well behind themselves, They finish the job in a timely manner and their price was fair. I would definitely hire them again."





+10

Serving Parkville, MD and surrounding areas
Approved (Corporate)
In business since 1945
Free estimates
Emergency services offered
"My husband and I were very happy with the service we received from ARS and we will continue to employee them for all our air conditioning needs."


Serving Parkville, MD and surrounding areas
Approved
Super Service Award Winner
In business since 2000
Free estimates
Warranties offered
Carroll Mechanical is an HVAC contractor that is dedicated to providing clients with the very best maintenance, repair, and installation services. We are based in Eldersburg and service customers throughout the MD region. We are a local business that is built on integrity, transparent pricing, and technical excellence. Our team of expert technicians have experience working with all major manufacturers. Our mission is to keep you comfortable and we proudly offer emergency availability where possible. If you are a homeowner, property manager, or business owner, give us a call today to learn more!



Serving Parkville, MD and surrounding areas
Approved (Corporate)
In business since 1982
Free estimates
Emergency services offered
"Paul S, the tech who came to maintain my furnace and air scrubber system was very knowledgeable, friendly, communicative and extremely helpful. The appointment system and text updates are terrific! Thank you to all!"


Serving Parkville, MD and surrounding areas
Approved
In business since 2013
Free estimates
Emergency services offered
"Very professional, good HVAC installation experience, very officiant, Cleaned up after work, did a excellent job installing heat pump outside and air handler on the attic"





+1

Serving Parkville, MD and surrounding areas
Approved
In business since 1989
Free estimates
Emergency services offered
"Fantastic company from start to finish! The gentleman who sold us the furnace, their salesman, Alex, was upfront in getting us the best price, along with a 10 yr parts and labor warranty included! The price for the furnace and installation was great, and they guaranteed apples to apples to meet any other companies cost. They offer a $100. fee if we found anyone to do it cheaper, with the same offer. They were able to schedule the intallation quickly, and did a great job intalling it. I would highly recommend using this company for your heating and air conditioning needs. Great company! Great prices! Great work! You won't be disappointed using Horizon Services! Take care....."





+27
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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