Gas and Oil Home Heating Furnaces - Air Handler problem

Outside Bryant unit replaced 4 years ago. Original air handler about 12 years old(in garage). Compressor went bad two months ago on 4 year old outside unit. New compressor replacement 600$. This week stopped cooling. Service man came out and replaced switch in unit(outside unit was not running) and all was well for 24hours. Now everything is running but not cooling. Service guy came back out and said some filter(?) on my air handler is clogged up. Two copper pipes come into the air handler unit, one small and one large(large one covered in foam insulation). He said the filter is on the inside of the unit where the smaller copper tubing comes in and then branches into smaller "fingers" I guess and then to the coils themselves. Anyway, he's not sure he can get the parts to repair and estimated $300 if he can get them( says because unit is old they don't make them anymore) .If he can't get parts $1300 for new air handler system. DOes this seem feasible? I mean I didn't even know of the filter inside the air handler. I looked and it's a verticle like copper aparatus that the smaller tube comes in to.

Thanks

Jeff

It sounds like the "filter inside" is a strainer ahead of the capillary tubes (very small tubes) that act as a restrictor to meter the refrigerant into the evaporator coil. The strainer screen can get dirty and restrictive and/or the capillary tubes themselves can become restricted by refrigerant oil breakdown compounds. (It is like varnish that coats the inside walls of the already small tube making its effective size to be too small.)

IF this were true, I would replace the coil with one designed to match the outdoor unit's size and efficiency. This means that it should be by the same manufacturer.

I would invest in a 2nd opinion. The tech should get ALL of the following nine items of DATA and tell you his opinion of the problem and solution:

Outdoor ambient- condenser air entering temperature
Outdoor condenser air leaving temperature
Return air temperature- air temperature entering the indoor coil
Supply air temperature- air temperature leaving the indoor coil
The wet bulb temperature of the return air
Head (high side) pressure
Liquid line temperature (Small line at the outdoor unit)
Back (low side) pressure
Suction line temperature (Big line at the outdoor unit)

THE UNIT MUST BE IN CONTINUOUS OPERATION FOR 12 MINUTES AND THE DATA COLLECTED IN A FIVE-MINUTE TIME SPAN. To get the wet bulb temperature, wrap a wet tissue around the sensor and hold in the return air stream for 90 seconds.

With that DATA, I can diagnose the proper or improper operation of your equipment and tell you what problem is or isn't.

Lynn,
Thank you for your response and th advice. I will get a second opinion and I'll get the data that you suggested.

It seems to me that though, that if this strainer filter was blocked with debri or whatever that the stsyem would freeze up after running it awhile. Is this true? My system wil jusr run and run without freezing up but just no cold air. Sometimes it does get a liitle cool but thats it.

Again,
thanks

Jeff

Ps: Is the $1300 about right for a air handler unit?

Another question.Sorry.

When they changed the compressor a couple of months ago they included two filters on two of the lines outside . ( two lines coming out of the outside unit). When they came back and fixed the switch he also said the those new filters were clogged and needed to be replaced. well he took both off and only replaced ONE. I asked him and he said that he thought that the other one had done it's job and that another one was not neccesary. Could their still have been alot of junk in the lines and actually really did need both replaced instead of just one. I mean since he did not replace the second one ( just took it off and replaced it with a piece of copper pipe) could the unit have sucked in remaining debri and clogged now the strainer filter you mentioned?

Thanks again

Jeff

1) The indoor coil can freeze up without providing much cooling if the metering device is only feeding 15 or 20% of the indoor coil. That part will be very cold and ice up quickly, but most of the air will bypass the cool part of the coil and receive no cooling at all.

The fans could run and run, but the compressor would overheat and shut off to protect itself. (The indoor fan and the outdoor fan would continue to run and you may not notice.)

2) The 2 filters were used to clean the system refrigerant and oil after the compressor failure. After 20 or 30 hours of run time, the one on the larger pipe should be removed. The other one can either remain or be replaced if the burnout was a dirty burn.

Copeland (a major compressor manufacturer) does not recommend a suction line filter-drier (the big one). The motor protection inside of modern compressors is so good that a dirty burnout is quite RARE. Also the system efficiency and capacity are lowered with a suction filter-drier in place.

3) $1300 is a good enough price (Installed). Installing an outdoor unit (only) is not a good idea technically. Economic reality is another matter. Too often, the benefits of a COMPLETE system are not explained so the homeowner can make an informed decision.

Being the week-end and no service man available for the second opinion, last night was hot , I live in Florida, and I have no a/c....so I took off the panels (again) of the air handler and with a heavy handled butter knife sarted tapping on the copper tubing inside. I started thinkiing that if the service man was correct and debri was clogging up the strainer filter etc, that MAYBE I could tap and dislodge whatever it is and it might go downstream to a less obstructive position. I tapped and tapped, everything I could reach with the butter knife. Tapped as hard as I dared without bending or mutalating. After a while I started feeling silly ( it was after midnight) so I quit and replaced the panels. Went back inside and flipped the unit on sure it was going to be unchanged and PRESTO, I HAD AIR. Do you believe it????? It ran great rest of the night and all day today. What do you think? Should I just see where this takes me or have the service man come back out. No freeze ups -everything running great.

Thanks again

Jeff

If you knocked some debris out of the way, it may find its way back. Wait and see.

Nest time it is serviced for ANY reason, get the data that I suggested and we will know more exactly how well it is operating. I am amazed that there was any effect at all form tapping on stuff, but I have been amazed before.