Room Air Conditioner Q&A
Be sure to scroll down... there may be more than one question on this page!
Dear NH,
I have a wall-unit air conditioner that has started dripping water on the
inside and down my wall. As this is a huge monster of a thing, I'm wary of
trying to tinker with it on my own. It still cools the air, although I don't
notice it getting as cold.
Since this problem only surfaced when the humidity skyrocketed, could this
just be condensation? What kept it from dribbling down my wall before?
KM from Cincinnati, OH
KM,
The two possible causes are 1) actual leak of rainwater from the outside or
2) condensation, which is a normal byproduct of the air conditioning process but
should be dripping outside your home, not into your wall! Since the amount of
condensation increases as the relative humidity outside increases, you are
correct to wonder whether there is a connection between the humidity and the
leakage.
You can locate the source of a rain leak by making a visual examination of
any weatherstripping or caulking around the outside of the machine itself, or
the sleeve that the "works" of the AC slides into. If you find any gaps or
openings in the caulk, you can scrape out the old caulk and replace it.
If there is a rain gutter over the AC unit, make sure that it is not blocked.
If the gutter were to overflow you could get leakage around the AC or through
the air vents in the frame even if the caulking seems OK due to the sheer volume
of water!
As I mentioned, the condensate from the AC normally flows to the outside and
exits the frame via weep holes in the frame (or pan). Some have preinstalled
rubber plugs underneath the pan, designed to allow condensate flow. Some
have accessory kits that allow you to install a hose to redirect this condensate
in dripping straight downward is not acceptable.
If the condensate exit holes are blocked, water can build up in the bottom of
the pan and potentially leak out where it shouldn't! You will have to examine
your unit to see where these weep holes are and if they are blocked. The usual
culprits are rust or paint chips that drop into the pan and block the weep
holes. This could also account for the sudden dripping!
AC units that slide into a preinstalled through-the-wall sleeve are often
installed level. The body (and tray) must be installed at a slight downward
angle towards the outside. Were the unit to somehow change level, it is possible
that the condensate would instead build up in the bottom of the frame and leak
into the walls. The only way to know for sure is to put a level on the frame to
see if it is level. If shifting has occurred you will need to modify the
mounting (either inside or outside) to restore the downward tilt.
To your other issue, the loss of cooling power is definitely attributable at
least in part to the increased humidity. Some of the cooling energy is being
used up drying up the moist air in your home. Dust on the cooling coils would
also cause loss of cooling power, and would worsen with increased humidity as
the dust holds the moisture, producing a damp insulating blanket on the coils.
Finally, mechanical problems with the coolant pump and/or a loss of coolant
pressure are other possible causes that should be investigated.
NH
Return to NH's Question and Answer Index
|