Thread: New A/C Compressor w/Old Air Handler

Located in southeast Florida, this past week inspected 3 homes where new compressors were installed without changing out the existing Air Handlers. All air handlers were located in attic with built up of midew/mold on units. I figured that contractors didn't want to deal with relocating new unit in small confines of attic. Still find it hard to believe that this is acceptable.
Two A/H I could trace mfg date by serial #'s back to being mfg in mid 1990's. The other one, an AMANA, seemed to be a 1990 model.
Appreciate input on this. Thanks guys.

Similar Threads:

• Air handler plenum
• mis matched condenser & handler
• Age of compressor
• air handler in crawlspace
• Fireplace Had It's Own Air Handler Unit

Joseph,

I assume you mean that new condensing units were installed.

More times than not, the home owner is the reason that partial replacements are installed. They don't want (or can't afford) a completely new system, so they replace the failed component. I see discarded and abandoned AHU's in attics around here frequently, as well as new ones with no left-overs remaining. They will replace them when given the chance.

If done "correctly" ( yes, I know...) by a skilled tech, it will work as good as can be expected. And for many home owners, that's good enough for them.

Dom.

Originally Posted by Joseph Melbourne

Located in southeast Florida, this past week inspected 3 homes where new compressors were installed without changing out the existing Air Handlers. All air handlers were located in attic with built up of midew/mold on units. I figured that contractors didn't want to deal with relocating new unit in small confines of attic. Still find it hard to believe that this is acceptable.
Two A/H I could trace mfg date by serial #'s back to being mfg in mid 1990's. The other one, an AMANA, seemed to be a 1990 model.
Appreciate input on this. Thanks guys.

Yep, it is not uncommon to find exactly what you discovered with a split system. Is it wrong? Depends on who you ask; most of the time as Dom noted it has to do with money. Homeowners can do pretty much what they want with their castle, that is what makes our profession so much fun!

From my understanding the new higher SEER units need a new A coil to be efficient. The matching A coils are larger.

Originally Posted by Robert Hronek

From my understanding the new higher SEER units need a new A coil to be efficient. The matching A coils are larger.

That is true if you want to have that SEER rating, if you don't care about it then it is what it is!

Thanks Guys, My concerns were with the new freon gas and life expectancy of old air handlers. And, I just didn't feel that it was the ethical thing to do.

Here is the general comment I made on a house I did yesterday. There were some specfic repair items that were listed in another comment.


"The house is heated and cooled by two heat pump split systems. Both air handlers are 1999 models. The outside heat pump unit for the top floor is a 1999 model. The outside heat pump unit for the first floor is a 2007 model. The normal life expectancy for this type of system is 12 to 15 years. The first floor system has a mis-matched outside heat pump and air handler that can affect the efficiency of the system."

Best practice is to change out both. But the quick and easy, down and dirty practice is to just change the condenser on older units.

The Compressor is a different story. The compressor replacement is just that, the only thing replaced is the compressor, gas and hopefully filter/drier.

With conversion to new refrigerant, it is a must. It is possible but not economically feasible to clean and convert the existing evaporator coil. The line sets should also be changed or at a minimum cleaned internally since old refrigerant and oil do not mix with the new refrigerant and oil.

The norm for condenser changes is, cheap same refrigerant units. Newer air handlers can be converted to 410-A if they have a TXV, the TXV can be changed without any loss of efficiency to the coil. The old line set can be reused if it is properly flushed out.

Usually the evaporator coils have about 1/4 or 1/2 the life of the condensing units in these parts.

Originally Posted by Joseph Melbourne

Located in southeast Florida, this past week inspected 3 homes where new compressors were installed without changing out the existing Air Handlers.

Still find it hard to believe that this is acceptable.

Originally Posted by Dom D'Agostino

I assume you mean that new condensing units were installed.

Dom is correct in adding the clarification on the wording.

It is not permissible to to change out just the outdoor unit (the condenser unit) and leave the air handler unit ... unless ... the air handler unit is new enough to be listed as a match for the condenser unit as meeting the minimum 13 SEER rating.

Jerry, that was my feeling, these 3 units were 15 vyears or older. How could they be matched with the newer unit of today. I realize owners were looking for cheapest way out. Perhaps no permits were pulled ?

As far as i can tell there is no code that says you can not have a mis-matched system. Here is what the DOE says:

Residential air conditioner systems (not window box air conditioners), manufactured after today must achieve a Seasonal Energy Efficiency Ratio (SEER) of 13 or higher. A SEER rating of 13 is 30 percent more efficient than the current 10 SEER standard. Equipment with a rating less than 13 SEER manufactured before today may still be sold and installed, and homeowners and builders can still buy 10 SEER residential air conditioners until the supply is exhausted.

Department of Energy - Stronger Manufacturers’ Energy Efficiency Standards for Residential Air Conditioners Go Into Effect Today

Originally Posted by James Duffin

As far as i can tell there is no code that says you can not have a mis-matched system.

There is a code which addresses that in Florida.

The city,or state can't "make you" replace an operable unit. It may not be the wisest thing to do, but it is still up to the homeowner to make the decision whether or not to update the air handler, or condenser, or furnace. As long as the system was up to code at the time of installation the point is moot.

Originally Posted by David Bell

The city,or state can't "make you" replace an operable unit. It may not be the wisest thing to do, but it is still up to the homeowner to make the decision whether or not to update the air handler, or condenser, or furnace. As long as the system was up to code at the time of installation the point is moot.

Apparently someone is not aware of building codes and what is and can be required.

A condenser change can be considered a repair to a system and not an install.

Originally Posted by David Bell

A condenser change can be considered a repair to a system and not an install.

Nope.

Go back and read the first post, Dom's post, and my reference to those two posts.

Maybe you will see what the difference is and why.

Mis-matched systems are fine in NC so what you folks do in FL does not apply....(thank goodness!)

Originally Posted by James Duffin

Mis-matched systems are fine in NC so what you folks do in FL does not apply....(thank goodness!)

James,

Go back to the original poster and see where he is from ... ... and you will see that what Florida does ... DOES APPLY ... thank goodness.