1. Home
  2. ⏣ General Metalworking
  3. Central A/C Problem

Central A/C Problem

Hope you guys can help. My A/C system has what actually may be 2 problems. Last month, I started to notice water (condensation?) around some of the outlet vents - mostly the ones closest to the air handler (which is in the attic). I pulled to cover off the evaporator to see if it was clogged; it wasn't, but in cleaning away the small amount of crud that had collected, I bent one of the capillary tubes, and it started to leak. Closed the valves on the condenser unit, let the pressure bleed off, and repaired the pin-hole with epoxy. Also found the condensate drain was plugged, so I blew it out, and figured that was the cause of the original problem. Recharged the unit, and put it back into service. The epoxy repair seems to be holding.

Now I am getting really poor cooling, and still getting the water at the vents. The drain line is still clear. The air flow is OK - just not cold enough (yesterday, the air coming out of the vents was 71, with the outside temp at 86). I still need to take a closer look at one of the return ducts to make sure it isn't leaking and sucking in hot, moist air, but I suspect it's OK. What other causes are there for the water at the vents (it really seems to be coming from inside the duct, not condensing on the outside and running down). Also, although I have a few books on A/C, they are heavy on theory, without much in the way of practical rule-of-thumb tips. My high side pressure is set at ~30 deg F above the outside ambient at the condenser unit, but I don't know what I should read on the low side (this is R-22). How can you tell if the filter/dryer is clogged? Any other ideas?

BTW, my air filters are clean, despite my cats' and dog's best efforts to plug them up.

TIA, Joe

PS - some of my ducts are sheet metal - to keep this on-topic for this NG.

Reply to
Joe
Loading thread data ...

Uh-oh.

(Please don't say you used JB Weld.)

You've obviously lost some charge, perhaps introduced air, and damaged a cap tube such that it won't do its job (even though you may have repaired the leak in an unorthodox fashion).

You need to repair/recharge the unit and the condensate drain first. That's more complicated than you've let on.

Reply to
Richard J Kinch

No comment on the charge/pressure but as for the filters...

If you have to frequently change filters on account of pet hair, there's a REAL good chance that your indoor coil is plastered over with a mat of crap that has got past the filter, and needs to be cleaned to regain sufficient air flow. (Create access to coil, spray with simple green etc., hose off, repeat)

We went through a heck of a time with this with a furnace that had to be half-disassembled just to get access to the coil to clean it. Not fun. Not wanting to ever deal with this again, I replaced the original filter rack with custom sheet metal that holds a commercial 2" pleated filter so tight that nothing can get by it.

Reply to
Bob Powell

Water at the vents means that the evaporator is running too cold. Two causes; either you do not have enough air flow or you have a low charge that lets part of the evaporator coil run cold and the rest is ambient.

Since you had a leak that you found when it hissed, I'll bet that you have had that leak for months, and that your system is way low on charge. But maybe not, read on:

You said that you recharged the unit and that you have pressure readings. This sort of implies that you have the standard 3 hose/2 gage refrigeration service unit. But you didn't say anything about a pump down of the evaporator. If not, you have air and mositure in the system.

I'd say it is time to have a pro pump the system down, leak check it, and recharge with clean R-22. Expect that they will want to replace the 'A' coil > Hope you guys can help. My A/C system has what actually may be 2

Reply to
RoyJ

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.