HV system air handler.

loumarch

I recently retired from HVAC work. I had a prior customer of mine buy a house that has an HV system in it.
His compressor siezed and it is R-22. He had a local company give him an estmate for a new system.
Their proposal lists a Coleman 3 ton air handler. He called and they said they would use the existing ductwork. He asked me what I thought and I told him to run away.
Has anyone ever put a standard air handler on an HV system? If so has the airflow been adequate to cool the space?

EBEBRATT-Ed

Not an HV expert but I always herd you could use a standard AHU and reduce the air flow

pecmsg

HV Systems can use anyone’s condensing units. Strict air flow and charges are required.

EBEBRATT-Ed

@pecmsg

Your right I was wrong had it backwards

motoguy128

Could get away with a standard unit but you would need to downsize capacity. Rheem and Carrier use 350cdm/ton as standard.

My preference would be a communicating variable speed air handler so you can verify system rpm to make sure you stay under max RPM. Some can tolerate over 1” of static and “survive”. If you are over 1.2”. Expect shortened motor life.

Alternately an x13 type ecm would be more reliable but. Might struggle to achieve target airflow.

If possible I would measure the current static pressure and airflow required for the system and see if you can match it up with a smaller system.

unclejohn

I agree run away. You need to install a new space pack and he will also need to replace at least the first 10' of duct to work with the new SP.

TAG

I had a spacepac years ago -- it used a common condenser and the proprietary space pac evaporator /fan assembly. There were any number of compatible condenser units from many companies suitable to match up.

The problem today would be finding a R12 condenser ..maybe just compressor switch is rest is on good shape.

pecmsg

A R-407C condensing unit will still work.