24/7 Emergency Service


Why is service/preventative maintenance so necessary for heating and air conditioning equipment?


Preventative maintenance or service is essential to the proper functioning of air conditioning and heating equipment. If preventative maintenance is not performed regularly or if it is done haphazardly, the equipment will require extensive and costly repairs at a later date that is sooner than it should be. This is not just a case of "pay me now or pay me later." It is a case of "pay me now or pay me considerably more, later," and lose reliability while paying higher repair and energy costs in the process.


Preventative maintenance programs for air conditioning and heating equipment include regular inspections each year. During these inspections, proper operation of the equipment is checked and verified. All mechanical equipment is designed to operate within certain limits. Air conditioning and heating equipment is no exception, and if not properly maintained, the equipment will exceed its design limitations with the result being equipment failure. Your best insurance against HVAC failure and cost containment is equipment preventive maintenance.

A Checklist for Preventive Maintenance


Why must we service and replace air conditioning filters? HVAC equipment is designed to operate within a specific quantity of air passing over its indoor coil surface. When air filters are not replaced, they clog and become coated with dirt. Similarly, the indoor coils get coated with dirt. This dirt reduces the amount of air through the unity below the design limit, leading to catastrophic failure.


In cooling mode, if there is not enough air over the indoor coil, the coil temperature drops. When it drops below the freezing point, ice forms on the coil, which further reduces the airflow, which further reduces the coil temperature. The compressor within the unit is a pump, which is designed to pump a vapor. As the airflow through the coil drops, there isn't enough heat being removed from the air passing over the coil to vaporize the liquid refrigerant inside the coil. Thus, instead of receiving a vapor, the compressor receives liquid refrigerant.


This is called "liquid slugging." The effect of "liquid slugging" is similar to the effect of pouring liquid into the cylinders of a gas engine. As liquids are not compressible, cylinder pressure exceeds the design limits of the cylinder, valves, connecting rods, pistons, or other internal components are destroyed. The air conditioning unit starts out requiring that its filters be replaced. Now it needs a new compressor. Preventative maintenance or  new compressor? Ultimately, it's your choice.

Sales & Service


State of Arizona Contractor Licenses:

L-04 164126, L-11 172243, L-39 164120

K-74 257869, K-77 264453,

K-79 256111


State of California Contractor License:



State of Texas Contractor License:



7845 East Redfield Road, Suite 100

Scottsdale, Arizona 85260


☎ 480-998-9620 | 866-998-9620 | Fax 480-998-9621

Copyright © 2018 Sunstate Mechanical Services | Terms and Conditions | Privacy Policy | Designed & Maintained by Avion Marketing