I live in Colorado, and am having problems with my evaporative cooler.
After running for about an hour or so, the fan always shuts off, even
though the water pump continues to run. This applies for all settings
(high cool, low cool, high vent, low vent). After resting for an hour
or more it will work as normal.
The fact that the water pump is still running seems to tell me that the
problem is not electrical. Any ideas? is this normal for swamp
Any help is much appreciated!
The motor probably gets too hot and the thermal
cutoff opens. When it cools sufficiently the
cutoff snaps shut and the motor starts.
You have a problem. When was the last maintenance
done and how old is the motor? most likely the
fan bearings or the motor bearings are going. Fan
bearings are cheap and can be easily replaced if
you are a do-it-yourselfer. If the motor bearings
are bad, the easiest and likely the cheapest
solution is to just buy another motor.
You can tell if the bearings are bad if after you
loosen the motor and remove the fan belt you can
move the motor shaft any perceptible amount at a
right angle to the motor shaft. Same with the fan
Most coolers have an adjustable pulley on the motor shaft. A good
installer is supposed to set the pulley diameter adjustment so the motor
runs at it's rated current. It sounds like your motor is overloaded and
that is tripping the built-in thermal cutoff. Have somebody who knows
what they're doing go up there and adjust the pulley for the proper loading.
I live in New Mexico and have a similar problem. Just this season, when
the fan is on "high" (I only have 2 settings), it will all of the
sudden slow down to low (for 5-30 seconds) and then speed back up again
to high. This has never happened before and I have lived in the house
for 3 summers. I do the maintenance myself, but I didn't notice
anything untoward when I was setting up the cooler this spring. It
sounds like it might be the motor and/or bearings? But how do I find
out? And is it easy to replace the motor? Thanks!!
The most common reason for the motor to periodocly shut off like this is
that it is over heating and the thermol protection system kicks in to
protect the motor.
The most common cause for a motor to over heat; is the belt is simply to
tight. You could have worn pillow bushings, but if they are causing that
much pull on the motor you would hear a god awful noise from them.
To test your belt tension grasp the belt between your thumb and forefinger
and apply light up & down pressure (approximatly 3 lbs). The belt should
only move about 3/4 to 1 inch.
To adjust the belt varies, usually you will find a bolt that holds the
motor mounting bracket. It is usually in a cresent shaped slot. Loosen
this bolt "a little" and move the motor toward the pulley slightly. If
you move it too much, just redo it until you can only move the belt as
above. If the belt is too loose, the worse that can happen is the belt
might slip a little.
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replying to coolerdoctor, Edification1 wrote:
I am having about the same problems since getting a new unit on the roof.
Everything is new except for a plug with wires for the pump to plug into.
Basically, I have a switch (hi-low cool /hi-low vent/ pump only) located in our
house, with a new 12/3 line hooked to it, that electrical line runs up into the
attic to a junction/splice box where another new 12/3 electrical line finishes
the run up to the motor/pump. I believe it is wired correctly, since the
installer just copied what was already there and I never had any issues with the
old unit shorting out/overheating. I have not checked the tension on the belt
yet, so I will do that tonight to see if that fixes the issue, but other than
that I am at a loss as to why it keeps shutting down. It's weird, in either of
the high settings it will just stop, when on the low settings it stops then
tries to start again going through various speeds to get back to low. Could it
be the old plug that is hooked up to the 12/3 line or could it be the splice in
the attic? I just don't know and would love some electrical help in this matter.
On Thursday, May 31, 2018 at 11:44:06 AM UTC-4, Edification1 wrote:
"Everything is new except for a plug with wires for the pump to plug into. "
You can't plug a plug into a plug. Seems this is easy to diagnose with
a volt meter when it's having the problem. If it's a new unit, who installed
it and why not just call them?
replying to trader_4, Edification1 wrote:
The plug (no cord, just the outlet and the wires) is female, and it is wired to
the 12/3 line, the pump has a power cord that plugs into it. The motor is hard
wired directly to the 12/3 line, (no power cord on the motor)They were in charge
of installing the swamp cooler, pump, and waterline. They want to charge me 300
hundred more dollars to do wiring. It worked just fine with the old motor,
wired exactly the same as it is now.
On Thursday, May 31, 2018 at 8:14:11 PM UTC-4, Edification1 wrote:
That's called a receptacle.
the pump has a power cord that plugs into it. The motor is
Why, was there something wrong with the existing wiring and circuit? Normally you would not change the wiring, just the equipment. And if it's new gear that they installed recently, what's the warranty? Seems they should come fix it.
It worked just fine with the
replying to trader_4, Edification1 wrote:
Everything worked fine before all the new stuff was installed, that's all I
know. When they mounted the swamp cooler on the roof, the motor position
changed by about two feet. The original wiring wasn't long enough to make the
run, so the installers attached a two foot piece of 12/3 wire to complete the
circuit. That is why I initially thought it was all the wiring splices that was
causing the short circuit, hence the new line. But I adjusted my belt last
night, loosened it alittle bit, and now it works fine in both low settings, but
on high it shuts off after 10 minutes. Any advice, other than having them come
out and possibly mess things up worse? I am trying to sell my house asap,
already have a closing date and all that so looking for some fast answers that
can be applied before this Monday.
From your description it seems that the motor is overheating. When
you disconnect the belt from the motor does the large fan pulley move
freely and smoothly? What about the shaft on the motor?
It is possible that there is a defective bearing in one or the other.
I would call the installer and have them resolve the issue as the unit
On Friday, June 1, 2018 at 9:44:05 AM UTC-4, Edification1 wrote:
I have the feeling that there must be more to this story. If you just
had this installed, you have a closing on Monday to sell the place, you
don't have the skills to diagnose it yourself, why haven't you called
the company that recently installed it? Sounds to me like this is one
that fell off the back of a truck and was installed by some hack on
the cheap or something. I can see someone who has the skills maybe
wanting to poke around first to find out what's wrong, but that doesn't
appear to be the case here.
Did this come as one brand new unit? If so, then we can assume the motor
is correctly sized for the blower. So, if it were me, like I said in
my first reply, I'd take voltage measurements when it's running and
especially when it's not. Running is there ~240V (assuming that's the
motor voltage)? When it's not, is there voltage at the motor terminals?
Is there a wiring diagram that shows any interlocks, safeties? Does
the blower move reasonably freely by hand? The symptom of shutting off
only on high would point to an overloaded motor that cuts off when it
overheats. Is the motor hot when it stops?
replying to trader_4, Edification1 wrote:
It was installed "professionally" superior water and air did the install. I am
having them come back out to find the solution, I'm done trying to fix someone
else's mistakes. Thank you though for the imput! I really appreciate all the
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