We recommend once every 3 months at the most. If you have pets, doing construction in your home or live in a dusty area, we recommend once a month.


In most cases, in residential homes that are not mobile home, we recommend a pleated filter with a Merv rating of 8. A filter with a higher Merv rating has a tighter weave and less air is able to travel through therefore causing the furnace to not be able to breathe which leads to further issues.
If you are wanting to use a higher Merv rated filter for allergy reasons, we suggest still using the Merv 8 filter and change the filter every 2-4 weeks. There are other solutions for allergy prevention that can be discussed with our Comfort Advisor or look at our “Air Quality Page” on our website.
For mobile homes, we suggest a poly filter in most applications.
Every furnace takes a certain sized filter, if you are unsure of the size of filter your furnace requires, please contact us.


Just like taking your car in for maintenance, your HVAC system needs maintenance as well. There are parts in both units that get dirty and need cleaned, electronic components that need to be checked, adjustments that might need to be made for peak efficiency, and electrical and safety connections that should be checked regularly. In our 40 years of business, we have noticed that homeowners who regularly maintain their HVAC equipment (furnace, humidifier, air conditioner, thermostat, etc.) run their system more efficiently, saving on utility bills, have less problems with their equipment, and gain a longer life span out of their equipment.

We offer a maintenance plan called the “Comfort Care Plan” that covers maintenance of your HVAC equipment, no matter what that comprises of. Our Plan offers some perks that you definitely want to check out!


In the Fall, schedule your maintenance for the furnace. In the Spring, anytime after May 1, schedule maintenance for your air conditioner. The weather must be above 55 degrees for the readings of your air conditioner to be accurate. Additionally, we will not perform a maintenance of your air conditioner when it is raining as the technician is working with electrical components. Sometimes we have to reschedule your maintenance due to weather conditions.

Our schedule books up quickly for maintenances (precision tune-ups) especially during our short 3-month summer period. To ensure you get on the schedule when you prefer, we suggest scheduling your precision tune-up one month ahead.


Yes. Simply turn your thermostat to cool and set it above 72 degrees to start. If there seems to be problems with your A/C, call us for a service call.


Call your utility company immediately! For our area that might be MDU (Montana Dakota Utilities) 1-800-638-3278 or 911 for the fire department. Comfort Heating & A/C, LLC cannot help in this situation.


We install and replace furnaces and air conditioners, including roof top units, in residential and commercial applications. We can service most makes and models of furnaces, air conditioners and roof top units. We sell parts for most HVAC equipment if they are still in production. We install HVAC equipment for new construction, residential and commercial. We also install fireplaces for new residential and remodel homes. In addition, we provide ventilation installs or repairs.
We offer estimates at no cost within our service area. Our Comfort Advisor can assess the efficiency of your current HVAC equipment and offer suggestions for higher efficiency, allergy issues, and tips for maintaining your equipment.


We install primarily Rheem furnaces and air conditioners and Mitsubishi Ductless Systems. Check out our “Products” page for more brands we sell and information about them.


  • Duct or Vent cleaning – we can provide recommendations.
  • Water heaters – in the state of Montana, a plumber must work on and install water heaters. We do provide services for the ventilation of water heaters.
  • Boilers are best for a plumber to work on as they involve water.
  • Geo Thermal systems or Ground Source Heat systems – we can provide recommendations.
  • Appliances of any kind
  • Fireplaces – we will service the fireplace only if we installed the fireplace.


No, we do not have a license to work in Wyoming.


Unfortunately, we do not work with maintenance companies for residential or commercial applications as we have had too many negative experiences with them in the past.


No, you will cause problems with your air conditioning system, such as freezing up the A/C unit.