Portable Air Conditioner Problem...A/C isn't working

15 years ago

Hi-

I have a Delonghi PL90. It was working fine this summer, and then the other day for a few days in a row, it didn't seem to be giving out cold air at all. The fan still worked, there were no strange noises, but no cold air. Then after about three days there was a really foul smell (burnt rubber) coming out. We shut it down and are trying to figure out what happened.

I opened up the unit tonight and found some gunk had 'melted' on some of the coils and the bottom of the unit. The stuff is like black oily putty with a thin layer of clear plastic around it. This stuff covers some copper piping elsewhere in the unit too that hasn't been affected. Looks like some sort of insulation. The burnt smell seemed strongest however in the metal box that houses the starter capacitor (I think that's what it is-see last picture).

If the starter capacitor did in fact burn out, would the fan still blow though? (it does blow strong, just without cold air). I thought this thing turned on both the fan and the compressor.

Or am I more likely looking at a bad compressor?

See pictures below:

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Comments (2)

zl700
15 years ago
That rubber stuff that burnt is insulation that is used to keep the copper coils from vibrating and rubbing which would wear a hole.

Due to the fact that it stopped cooling and burned the insulation, I would suspect that the coil on the bottom (condenser coil) got too hot because the condenser fan stopped working or is blocked. IÂm not familiar with this brand but, either the fan has failed or something blocked the vent pipes to the outside.

Given that you still had air blowing indoors, I would suspect that you have individual fans (2) so one fan stopped working or the vent pipe outdoors is blocked.
MiniSplit Heat
4 years ago
My AC Isn't Providing Enough Cooling.

Portable air conditioners are ideal for cooling small areas, such as bedrooms or living rooms, or for providing supplemental cooling in places central AC systems can't reach. Because they're small units, the two primary reasons for inadequate cooling are incorrect sizing and extreme ambient temperatures.

The size of an air conditioner refers to its cooling power, not its physical proportions. Portable ACs are sized according to their BTU ratings, and if your portable AC has the wrong BTU rating for the size of the room you're trying to cool, its efficiency will be affected. A unit with too many BUTs will cause the unit to cycle off too quickly, while a unit with too few won't be powerful enough to affect the ambient temperature.

To find out whether your portable air conditioner is the right size for the room it's in, measure the length and width of the room. If your room is oddly shaped, try breaking it up into smaller shapes like squares and triangles. Calculate the area of a triangle my multiplying the base by the height and dividing in two. Once you've calculated the area, consult our portable air conditioner sizing guide to see what size air conditioner will work best in that space. If you're on the cusp of two different sizes, always choose the bigger one. It's okay to have a little more BTU than you need, just so long as it's close to the correct size.

On the other hand, if the ambient temperature is too high, it can also cause insufficient cooling. As portable AC units release cool air out into the room, they vent hot air from the compressor outside. This constant venting causes a pressure imbalance that pulls in warm air from the other areas, including adjoining rooms and the outdoors.

Normally, if the room is properly sealed and all the doors and windows are closed, the air coming is never enough to overwhelm the portable AC unit. If there's a leak, or if the outside temperature is extremely high, the air conditioner may not be able to generate enough cold air to cool the room. Sunlight can also heat a room faster than your portable air conditioner can cool it. If temperature keeps rising, check for leaks and close the blinds. It may be enough to swing things the other way.
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Portable Air Conditioner Problem...A/C isn't working

Comments (2)

zl700

MiniSplit Heat

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