Serving Reisterstown, 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 Reisterstown, MD and surrounding areas
Approved
In business since 1978
Free estimates
Credit card accepted
When looking for professional HVAC services, look no further than GLM Mechanical Services, Inc. \nWhat we offer is honest, open estimating, with strict attention to detail and on time delivery. All we ask is when calling PLEASE speak english. WE can't help you if we can't understand what you need to tell us. Unfortunately, we do not offer attic installations when outdoor temperatures are so hot that attic temperatures can reach 100 degrees or higher. We cannot ask our employees to work under those conditions. We can bring to the table a level of expertise not usually available to residential projects. We have several years experience providing prompt and reliable services building your dreams into reality. We will always meet and exceed all expectations. Proudly handling the Goodman and Airtemp brands of HVAC equipment. Give us a call, you will be glad you did. \n \nWe now accept Visa, Mastercard, & Discover.
Serving Reisterstown, MD and surrounding areas
Approved
Super Service Award Winner
In business since 2000
Free estimates
Emergency services offered
"I would absolutely recommend Carroll Mechanical. Their customer service was exceptional. After our heat pump failed, I reached out to learn more about upgrading our system. I spoke with Janel and she quickly scheduled an appointment for their expert (Chris) to come out to our house and talk us through our options. He educated us on the different systems on the market and the pros and cons of each. He was honest and not pushy (unlike some companies in the area?). The quote they sent was detailed and transparent. We decided to go with a new energy-efficient system and were able to schedule the install for the next day. The high efficiency system qualified for a tax credit and utility company rebate, which Carroll Mechanical handled for me. That added up to $4k of savings!! The install team was professional, courteous, and took their time to make sure everything was installed correctly. What i loved the most was the attention to detail. They took the time to explain how to operate the"
Serving Reisterstown, 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 Reisterstown, 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 Reisterstown, 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 Reisterstown, 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
Serving Reisterstown, 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 Reisterstown, MD and surrounding areas
Approved
In business since 2025
Emergency services offered
Small jobs welcome
"Great company came serviced my unit and got my heat working"
+23
Serving Reisterstown, MD and surrounding areas
Approved
In business since 2005
Emergency services offered
Warranties offered
"John the technician Norwood sent was very pleasant and highly skilled and immediately solved my air conditioning problem."
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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