We’ve had numerous questions over the last few weeks where a heating contractor is replacing a heat pump system for a homeowner and they want to use the existing air handler and just replace the coil inside. There are various reasons why you can’t or you shouldn’t replace only the coil. Instead, replace the entire air handler.
- The minimum efficiency is 14 SEER, it’s practically impossible to find a coil that will t in the air handler that AHRI matches to the heat pump.
- If you decide to use a non-AHRI matching coil, the system is not going to work properly and will have significant operation issues.
- Replacing the entire system gives the homeowner a brand new system warranty on ALL parts.
We’ve seen the negative side effects when trying to match up a coil or selecting the wrong coil. We have seen liquid slugging back to the compressor in AC mode and head pressure issues in heating mode. Both of these issues can reduce the lifespan of the equipment.
It is fitting to also talk about airflow. Proper airflow must be set and verified before the charge can be checked. I always tell people that if I purchased a 3-ton system, I want 3 tons of air! Why sell a 3-ton system but only deliver 2 tons? Incorrect airflow can cause several issues like:
- Incorrect superheat and subcooling
- Poor humidity control
- Head pressure issues in heating mode
- Inefficient operation
- Nuisance lockouts
- Excessive use of backup heat, and more
As always, if you need any help with your heat pump, feel free to call the Famous Supply Tech support department at 330-962-2491.
BY JEFF ROSENBLUM – Training & Technical Support
& COLLIN MURPHY – Armstrong Air/Concord Equipment Specialist