Why can't I have Fan - Low?

June 4, 2007 1:15 PM

In-window air conditioner switch issue...I can't figure out how to google this, so I'm hoping someone here can understand my question!

We have a window shaker which is only 2-3 years old. It has a manual dial-type switch with 6 settings:
1) Off
2) Fan - High
3) Fan - Low
4) Cool - High
5) Cool - Medium
6) Cool - High

This year, when I put this thing in the window, it seems that only 3 settings work. It can be off, Fan - High, or Cool - Medium. If I move the dial to any other settings, I effectively get "Off".

I'm not an electrician, but I've owned a fair amount of appliances in my life, and never seen this behavior. Can anyone suggest why this is happening? Are there some contacts that I should be cleaning? Time to return, or bring in for service? Honestly, this A/C unit is making me feel dumb!

posted by Richat to home & garden (5 answers total)

Sounds to me like the contacts in the switch are bad.

If you have an ohm-meter (or a multimeter), and a little bit of know-how, you can (AFTER UNPLUGGING EVERYTHING and checking TWICE that it is REALLY UNPLUGGED) open the unit and check the switch with the meter.

If it's not a simple switch, or you don't feel comfortable doing that, bring it in for service.
posted by JMOZ at 2:13 PM on June 4, 2007

JMOZ is on the correct track. What happens with these types of window air conditioning units is with the removal and re-installation yearly, plus unknown storage and moving methods, the mechanical controls can take a beating. If you feel so inclined, you can follow JMOZ's advice, but more than likely you will find that the selector switch is faulty and needs to be replaced. Any appliance store can order the part for you, and install it if you do not feel comfortable doing it yourself.

Good luck.
posted by wile e at 3:08 PM on June 4, 2007

This is mostly likely a switch but it can also be caused by a single faulty or disconnected wire depending on the switch.

Some CRC switch cleaner/lube sprayed into the switch may fix it, often without taking anything but the face plate off. Do not use it on energized equipment (flammable till dried) and only use a switch contact cleaner, not something like WD-40.

Be very careful when/if you open the unit up, some of the wires maybe connected to capacitors which maybe at line potential even after the power is removed. The second worse electrical burn I ever received was from a large A/C capacitor.
posted by Mitheral at 4:53 PM on June 4, 2007

Thanks you guys, I had a feeling it was something like that. I may try the switch cleaner for now, until I decide I can't like with the two settings!
posted by Richat at 5:42 PM on June 4, 2007

Is there some kind of 'energy-saving' switch? And a temperature/thermostat dial? If the energy switch is on and the temperature is set high enough, the mechanics won't come on until the room temperature is high enough to match the temperature the thermostat is set to - turn the temp dial down, the fan and compressor kick in.

Just a thought.
posted by DandyRandy at 8:55 AM on June 5, 2007