I've always been in the habit of feeling the larger, cold fitting when
walking by the back yard unit to check the coldness.
CY: As you'd noticed, a good running AC has enough cooling power to
cool both the house, and also the cold refrigerant helps cool the
Nice and cold until
a few days ago. It then was only somewhat cool and had a little oily
substance on the cold fitting. I turned off the A/C right away until I
can get it checked.
CY: That's a cautious approach.
From what I gathered lurking here, a tech needs to
at least evacuate the entire system, ensure there are no leaks, and
recharge with brand new freon. I have some questions...
CY: From what you write, I'd expect a tech to use a leak detector
while the freon was still in the system. See if he can detect a leak.
After beeping to find a leak, then put the gages on and see what
pressures, superheat, adn so on. And, then, remove the freon and fix
the leak if a leak was found.
1) Generally, how much should I expect to spend if that’s all that is
needed? It’s a long run from the back yard compressor to the attic
furnace system towards the front of the two story house.
CY: Trip charge, plus labor, plus probably five or six pounds of
freon. Wild guess would be $300.
2) How do I find a reputable company with competent technicians?
CY: Ask your neighbors and friends who they use, and if they are happy
wtih the service.
3) Any other periodic maintenance that should be done?
CY: Change the air filter. Have a tech check the freon level in the
spring, and clean the condensor every couple years.
4) From day one, the lines in the outside wall by the back yard unit
have occasionally produce a pressure-relief-like swishing sound that
lasts for about 20 seconds. Is that bad?
CY: If it happens when the outdoor unit shuts off, that's just the
5) Are service rates seasonal? Higher rates in the summer?
CY: Yes, I'd expect so.
Thanks to the group.