Can the A-coil be installed on the return plenum of the furnace and not have any adverse affect on the system?

Question

there's a constant condensation at the middle just below the A-coil, the engineer suggested install a curved sheet so as to have a smooth air flow but it didn't work.Now the hvac guy suggested to move the coil on the return side. Will that not have a bad effect on the furnace parts since cold air will be b;owing directly on it?

Answer 1

Dear first please rule out the possibility of the problem with the unit. The problem could be an air flow issue, check the fan and make sure it is running on high speed.  It could be a installation problem, line size problem, units are mismatched, bad expansion valve.  Without knowing all of the operating data on the unit, one can not even start to give you any ideas.

From the language in your question you seem to be well acquainted with the maintenance problems of the HVAC system.

One out of the way solution is go ahead with the shifting of A-coil in the RA. But try to cap the existing return and make up for it with a new higher one that will pull from a spot higher up and also is common to the old returns area of work.

Many people don't try this because of the fear of the possible corrosion problems.  

t ahead and do whatever you need to do to make it fir

the existing duct. It will be just fine. The parts house just wants

to sell you more parts, or a more expensive unit.

Answer 2

You can install an a-coil in the return air. The effect it does have is the you will build up condensation on the inside of your furnas heat exchanger and unless it is stainless steel its going to rust sooner or later.

Answer 3

The A-coil can be installed in the return if your ductwork is set up properly. If it's not set up properly, it could pull moisture off the coil and into the ductwork.

FYI, the air coming off the coil is drier than the air going into it. Refrigerated air conditioning removes humidity from the air.

If your furnace has a sealed combusion system and the blower cabinet is insulated and the ductwork set up properly, you shouldn't have a problem.

If you don't have a sealed combustion chamber, you could have a problem. The cold air passing over the heat exchanger could drop it's temperature below the dew point of the air. Moisture could form on the inside of the heat exhanger and eventually cause damage.