Air Conditioners and the heat wave

[maraire]

The heat wave we are experiencing is ravaging central air conditioners. We are changing compressors at a very brisk rate. Don't get me wrong this is good for business, although bad for homeowners.

Check your outdoor unit... dirty coils on the outdoor unit are killing compressors. If your condenser is plugged with cottonwood hose it down or call a professional to clean it for you. You just may save yourself a rather large repair bill. A/c units need to be cleaned to inssure it doesn't run hot and burn out a compressor.

Just a friendly reminder from Martin-Aire

[OakParkSpartan]

Thanks Marty and Reg!

[Bonster]

I'm gonna hose mine down tonight.

I wonder if I should use any specific type of cleaner or just the hose.  I've seen some stuff for window A/C units "Koil Kleen" or something, but the outdoor condensers are so much bigger and probably need something else?

[berwynson]

Also VERY hard on compressors, even brand-new ones with clean consenser coils, are "semi-brown-out" conditions of sporadic low supply voltage.

This is harder to detect than dirty coils, and little can be done about it; during a period of high electric power demand, for example, the hottest part of the day, a voltmeter check of supply voltage showing more than 10% to 15% reduction in rated voltage, can spell doom for older compressors, especially. The reason for this is that as supply voltage FALLS, compressor current drawn (amps) INCREASES; this causes the compressor to get hotter and hotter, until it's overload device shuts it's current supply off. When that happens, the compressor motor's coils begin to cool off, the A/C unit begins blowing warm-feeling air, and the compressor "rests" until such time as it's overload turns it's voltage supply back "on". This cycle may take 15 minutes, or longer. Then it repeats itself, if the supply voltage has not risen  back up to acceptable levels.

The big problem with older compressors (especially), is that the overload devices are rarely designed to continue this type of cycling for extended periods, and often fail to do their job. Then, the compressor motor "roasts" itself. The vast majority of A/C units for homes are called "hermetically sealed" compressors. That means there are no drive belts, or other means of turning them, like on your car. Hermetics give the designers the extremely dubious ability to PASS the cooled refrigerant (freon) directly through the motor coils, thus allowing design degradement of size of wire used, etc. So, a percentage of cooled refrigerant, instead of cooling the building, serves to cool an undersized, by design compressor motor. Thus, a "burn-out" of compressor motor fills the entire refrigerant circulation system, with products of burned insulatuion, charred shit of the nastiest persuasion! The fix, then, involves flushing the system to cleanse it of all the burnt crap; failure to do this places a newly-installed compressor in serious jeopardy.

As consumers, we experience it being "slipped" to us quite often!     berwynson