Greathouse Mechanical LLC. | Mt Vernon IL

2017 and 2018 RUUD Pro Partner Top Selling Energy Efficient Contractor. 2018 RUUD Pro Partner fastest growing contractor.




Very thorough maintenance. Provided a nice report with readings and pictures. Takes it to a new level from the competitors in the area.
— N. Smith
Very high tech, fast and reasonbly priced
— G.J. Finn


About Us

We are a 24 hour service and HVAC Contractor. Our rates are competitive, and along with our high tech system analyst, we can offer our clients peace of mind. We show our clients in real time whats happening with their system. Maintenance plans and system analyst help to build a system history. That can save our clients money.
We offer Financing for all services $300 to $35000. So If you want that new energy efficient system this year. You may not have to pay until next year. For more information on our financing please call, email, or feel free to fill out the application and get preapproval.

We Service Mount Vernon, Centralia, Salem, Fairfield, Wayne City, Woodlawn, Waltonville, Benton, Nashville, Ashley, Ina, Bonnie, Dix, Texico, Kell, Odin, Sandoval, and all areas in between.


Heating and Air Conditioning Services.

Quality Repair,Installation and Customer Service.

Skilled craftsmanship with a technological advantage over the competition. We use the latest in technologies to test and service equipment. We can prove to our clients what is wrong, and what has been done to correct it. We can also help prevent future failures and high energy bills with our testing and analyzing equipment. Our Maintenance programs are tailored to fit each client. This helps keep the cost of maintenance down.  Please call or message us today we can help with all your HVAC needs. We also offer energy auditing services to help you remedy your heating and cooling losses. That can save you BIG!

Financing Application click here.


Thank you for coming to my house on short notice. Talking me though everything, very high tech. Highly recommended
— Joetta Devine


A thermographic inspection is either an interior or exterior survey. The inspector decides which method would give the best results under certain weather conditions. Interior scans are more common, because warm air escaping from a building does not always move through the walls in a straight line. Heat loss detected in one area of the outside wall might originate at some other location on the inside of the wall. Also, it is harder to detect temperature differences on the outside surface of the building during windy weather. Because of this difficulty, interior surveys are generally more accurate because they benefit from reduced air movement.

Thermography uses specially designed infrared video or still cameras to make images (called thermograms) that show surface heat variations. This technology has a number of applications. Thermograms of electrical systems can detect abnormally hot electrical connections or components. Thermograms of mechanical systems can detect the heat created by excessive friction. Energy auditors use thermography as a tool to help detect heat losses and air leakage in building envelopes.

Infrared scanning allows Greathouse Mechanical to check the effectiveness of insulation in a building's construction. The resulting thermograms help Greathouse Mechanical determine whether a building needs insulation and where in the building it should go. Because wet insulation conducts heat faster than dry insulation, thermographic scans of roofs can often detect roof leaks.

In addition to using thermography to determine the best HVAC system to install. Having a scan done before purchasing a house; even new houses can have defects in their thermal envelopes. You may wish to include a clause in the contract requiring a thermographic scan of the house. A thermographic scan performed by a certified technician is usually accurate enough to use as documentation in court proceedings. 


He was great. Very kind and nice. Took the time to show and explain what was wrong . Had my air going within a hour . He did an amazing good .. 110 percent satisfied


Free Estimate

All estimates are free and flexible according to materials and scheduling.


Service         Rate  

Repair Call :                     $65 Call fee $75 Hr

installation :                      $65 Hr per Tech.

Maintenance :          Cost included in Contract

Energy ASSESSMENT :         starting at $100                      





Contact Us



Phone: 618-472-1407


Facebook: Click here.