How to Winterize a Swamp (Evaporative) Cooler
October 21 - 22, 2013
If you have never lived in the
Southwest or in another arid climate, you have
probably never heard of or used a swamp cooler.
Before my husband and I bought this house we were
clueless. We both came from more humid regions
where only air conditioners were used to cool a
For years this was my husband's dreaded piece of
equipment to maintain. I would point out the
problems as they occurred:
"Honey, there is water coming off the roof!"
"Darling, the cooler is blowing warm air."
"Oh, dear, what is that rattling sound coming from
He would dutifully drag out the ladder, grab his
tools and climb on the roof to look at the
evaporative monster. Which was frequently
followed by a trip to the hardware store to buy a
Then as the years past, my husband was
working out of town many times during the
summer and fall months. The
responsibility of maintaining the cooler
Preparation -- Or A Freeze is Coming
NOW....What Do I Do? (Nov 12, 2014)
If you waited until the last minute and that
first winter freeze is
coming....like....NOW. Then follow the
steps here and do the rest later:
1) Turn off the water to your swamp cooler.
2) If your water line is outside.
Remove it or make darn sure all of the water
is out of the line.
3) Cut off the power to the cooler.
Pull the plugs.
4) Drain all of the water out of the swamp
cooler. All of it!!
5) If your swamp cooler has a damper....
which is the metal thing that slides between
the cooler and your duct system, get it in.
Or all of your heat will go out.
6) If you have no damper, cover your
cooler. If you can't find a real
cover, plastic bags and duct tape work in a
pinch. Block anywhere cold air can get
into your house.
I had two choices for
taking care of the cooler, call a company that
specializes in evaporative coolers to fix the
problems or do it myself.
OK, the idea of climbing up on the roof was daunting
to me. I trip over cracks on sidewalks.
If I get up on the roof, I will probably fall off
and kill myself. So I paid for a company to
maintain the cooler. This went on for only two years
and the service was OK. It was not cheap.
Until I had a really lousy service man to turn the
cooler on, Spring 2012. Not only did the punk
have an attitude, he was kind of clueless about what
should be done. He only did the bare basics
and did not fully prepare the machine. At this
point, I decided to teach myself how to maintain the
The Fall of 2012 I taught myself how to winterize my
swamp cooler. I first looked at the manual. I
then made a few phone calls to my husband to confirm
what the manual said. It was pretty clear cut.
I also phoned him to let him know when I was going
on the roof and I would call him when I got down.
If I did not call him back in a couple of hours, he
should call 911 because I probably fell off the
It is now Fall 2013, and based on the maintenance I
have had to do all summer, the steps I follow this
Fall are going to be done to help shorten the amount
of things I will have to do in the spring when I
turn the cooler back on.
For instance, last year I drained the water from the
unit, but did not clean out the mineral build-up.
I deciding last year to wait until spring to do
that. Not this year.
The first thing to do was gather the tools I would
||- Socket set (to
remove the bolts on the panels)
||- A flat head and
Phillips head screw drivers (just in case)
||- My large flat
head screw driver for prying something if
||- Pliers and a slip
||- A giant twist tie to
tie up electrical plugs
||- WD-40 to
loosen nuts and help get the damper in
||- Plastic scrapper to
scrape off mineral build-up (NOT a metal
||- Plastic bags to
dispose of mineral build-up waste and to
carry everything to and from the roof
||- Ladder to get on
||- Swamp cooler damper
(flat aluminum piece below)
||- Swamp cooler cover
(Oil cloth, made to fit swamp
||- Gloves, just in case
my hands start getting too cut up.
||- Proper attire -
loose pair of sweat pants, long sleeve
t-shirt and floppy hat that covers back of
my neck to prevent sunburn, shoes that cover
feet and won't come off.
||Of note: I needed later; a wire
coat hanger, vinegar, plastic container, green scrub pads, a
little wisk broom, and a scrub brush for
cleaning. Also, a large plastic
contractor's bag and duct tape to cover the cooler panel with
Items to take to the roof
With pliers I removed copper
tubing from the water source
Before climbing on the roof, I
disconnected the copper tubing that leads to the
swamp cooler at the valve on the water source.
My swamp cooler valve is on the outside of the house
welded onto the side of an outdoor faucet. The
copper tube runs up over the roof to the swamp
The valve was already turned off
because I had not used the swamp cooler for about 2
weeks. You need to disconnect the tube
from the water source to drain any water in the
tubing to protect it from freezing. Since I am
doing this weeks before a freeze, the inside of the
pipe will have a chance to drain any water in it and
After I removed the pipe, I discovered that my valve
had a leak. I did tighten all of the nuts to
confirm this. I contacted a plumber to come and
repair this now, before winter. Since he was
not available until the next day, I put a bucket
underneath to catch the water.
Copper tubing going up to the
swamp cooler. Yes I know, I have peeling
paint on the beams which were painted in
I will watch the plumber
closely to learn how to do this. This
way I can fix it the next time by myself.
The picture below shows the swamp cooler on
the roof. Copper tubing winds its way
down the roof.
The brand and model of this cooler is a
MasterCool Model ADA71. It was purchased May
of 2011 when our last model, that lasted 10
years, rusted away and finally died.
The cooler got a few dents in it when my
husband and his friend hauled it on the roof.
These coolers are very heavy and it was not
easy for them.
White stuff on roof is from past water
(The wood beams with peeling paint have been
taken care of.
See the wood beams here...)
Cooler on the roof. The
mountains in the background are in Mexico.
East side of cooler with damaged
panel to be removed
The swamp cooler has three panels
that I will remove. The first panel I remove
is on the east side of the cooler housing. I remove
this panel first because this side has the electrical outlet.
This panel was badly damaged in Spring 2012 when
some high winds ripped it off. Fortunately the
panel landed in my yard and not down the street.
This is the reason I now put a cover over the whole
cooler during the winter and spring. To hold
First panel removed. Blower housing
is the round object inside.
Outlet inside of cooler
two items that plug into the outlet; the cooler
the water pump.
Both plugs should be unplugged
before working on the cooler.
I unplug both and tie
the cords out of the way with the long twist tie I
had with me. I don't want the cords dangling
in the water.
I also removed the copper tubing that was
attached to the cooler. I want the air
to circulate through the tubing to
thoroughly dry it out. I needed to use
WD-40 to loosen the bolt.
Electrical cords twist-tied out of
Copper tubing removed from cooler
Panel on north end to be remove
The next panel to remove was the one on the north end
of my cooler. This panel gives you access to
the cooling pads. This panel comes out without
screws. You lift it up a little, then pull it out.
But to remove the cooling pads, you have to remove
the panel on top also. These two panels can be
removed in either order.
North panel removed by lifting out.
Cooling pads now exposed.
Top panel removed
Water hose removed from Water
The black thing that sits on top
of the pads is the Water Distribution Housing.
It has a water
tube inside that distributes the water to the pads.
The water is pumped here from the water pump through a
hose. This hose needs to removed before the
Water Distribution Housing is removed.
Pads removed from the cooler
Once the water distribution housing is removed, the
pads lift out easily. You now have access to
the water reservoir below. This is where most
swamp coolers get real ugly. All the white stuff is
the mineral build up. El Paso has really hard
water. There is also dirt that has collected
in the reservoir. The water needs to be
drained and the reservoir cleaned out.
Important--No matter what, the water has to
be drained. You can wait until spring to do
the cleaning, if you don't want to do it at this
This year, I am doing the cleaning during the fall,
so I don't have to do it in the spring. To
remove the water for this cooler, there is a drain
plug. My problem with it last year was the
difficulty of getting under the cooler to loosen it
and tighten it back up. So I decided to scoop
the water out with a plastic container. I
soaked up the excess water with a rag.
Reservoir being cleaned up
The photo above shows the reservoir as I begin to
clean it. I am scrapping up what I can while I
wait for it to dry out. I will remove the
water pump on the right to clean it up also.
The reservoir is made of plastic. This is why
I am only using a plastic scrapper. If I
become over zealous with a metal scrapper, I may put
a hole in the plastic.
Water pump and water distribution housing to be
I decided to wait until the reservoir dried out a
bit to clean it further. I took the water distribution housing and
water pump off the roof so I could clean them.
The pump is only a few months old and the reservoir
and the tube were cleaned in June. The tube
had become clogged at that time. I wanted it
cleaned out now so it won't clog next summer.
First I had to remove the tube from the housing.
With my pliers I removed the plastic piece that
holds the tube on.
White piece that holds water pipe onto water
distribution housing. Remove with pliers
Removed water tube showing holes
|The photo on the left shows
the pvc tube with the holes which cannot be
seen when the tube is attached to the
Needless to say, the holes plug up first
before the whole tube.
To clean the holes, I use a small Phillips
screw driver which just fit inside the
holes. I place it in to each and every hole to clean
I then use my straightened wire coat hanger
to scrape the inside of the tube. It
just about reaches down the entire tube.
I then set the tube back in the housing
and tilted it slightly and pored some white
vinegar in to soak it. I tilted the
little to keep the vinegar from running out
of the hole in the housing. The tube was not completely covered
so I rotated it an hour later.
Screw driver used to unplug the holes.
Tube soaking in vinegar
Removed bottom tray from water pump to clean
While the tube was soaking I went to work on the
water pump. I removed the tray on the bottom
of the pump. I got off most of the dirt and then
soaked it in vinegar. I also cleaned the
bottom half of the pump to clean off the dirt and
mineral build up.
DO NOT get water in the top half of the pump.
This part is not waterproof. I ran the coat
hanger down the water tube portion of the pump to
make sure there were no debris. I then set the
pump in a bowl of water in the sink and plugged it
in to flush out any dirt and to make sure it was
pumping properly. It was.
I also pored some vinegar into the hose that goes
between the pump and the water distribution housing
to clean it out. I also ran the coat hanger
through the hose to make sure there were no debris
With everything cleaned out, I put everything back
Cleaned up water distribution housing with water
delivery tube attached.
Cleaned up water pump and attached hose to tube on
the water distribution housing
I carried the cleaned housing and
pump back up to the roof.
I cleaned up a little more in the reservoir and then
pored some vinegar in the reservoir to soak over
I decide to complete the rest tomorrow. But before I
tucked everything away, I decided to put the damper
Install the Damper
This cooler is a downdraft cooler. Meaning the
air is forced down into the house. The ducts
in the house are used for heating and cooling.
If I do not put the cooler damper in, all of my
furnace heat will go out of the roof through the
cooler hole. The damper needs to be installed
between (under) the cooler and the roof. Which
means I have to lay on my back and slide under the
cooler to get the damper in.
In the photo above you can see the very tight slit
that the damper will go in. About 2" from the
bottom of the cooler.
The photo above shows the damper half way in.
I spray on a lot of WD-40 to get this done and more
to finish the job.
The photo above shows the damper
all the way in. It hangs out about an inch.
I then poked my head inside the blower housing to
make sure the damper completely covered the hole on
top of the duct..
Reservoir cleaned up and water pump
put back in place
The next morning I climbed back
on the roof to check how the vinegar I pored in the
reservoir did. It got most of the minerals
off. I soaked up the vinegar to dry out the
reservoir and ran my dust broom through to get out
any remaining loose pieces. The photo above
shows the final clean-up. It is almost
impossible to get all of the white off.
Perhaps if I soaked it a few more days. But I wanted
to finish this job up today.
Plastic bag duct taped onto north
panel along top
cleaned the north panel, the one with the
holes in it. I wanted to get off the
mineral build-up in the lower right corner
where the reservoir had over flowed in the
What I had decided to do overnight was to
remove the cooling pads, clean them, and
then store them in the garage in plastic
bags until the spring. It seems silly
to clean them now and then have to hose them
down again in the spring to get off the
The problem that no pads would cause would
be the holes in the north panel. They would
let dust into the whole unit without the
pads to stop the flow of air. So I
came up with the idea of covering the holes
with a bag.
Granted ,the cooler housing is not air
tight, but this would keep most of the dust
So I used a thick contractor
plastic bag. Taped it with duct tape along the
top edge of the panel leaving the other three edges
I then put the
panel in place allowing the three loose edges of the
bag to be caught against the edge. The panel
edge will hold the bag in place. I then placed
the top panel and side panel back on and secured all
of the screws. I used a piece of duct tape to secure
the copper tubing that was flopping loose against
the side of the housing.
Before putting the panel on, I stored the water
distribution housing that I had cleaned inside the
With no cooling pads to move out of the way in the
spring, all I will have to do is wipe off some
surface dust, slide the cooling pads back in,
reconnect the hose between the pump and water
distribution housing, plug in the blower and pump,
and hook up the water supply. I should be able
to do all of this in about 15 minutes.
In the spring I will also
check on the tension of the belt and probably oil
some of the moving parts. Neither should take much
time unless I have to replace the belt.
Cooler panels all back on. Plastic
bag blocking holes pinned down by edges of north
With the cooler finally closed
back up all I had left to do on the roof was place
the cooler cover on.
Swamp cooler covered and ready for
As for the pads, I sprayed them
with white vinegar to get off some of the mineral
After letting them soak for a few hours, I hosed
them down. I then left them out for a few days
to totally dry. I then placed them in plastic bags
and stored them in the garage.
I only purchased the
pads this past summer, so the pads are good for at
least one or two more summers before they become too
crusted up with minerals to be useful. You can
see in the picture below that they are still in
pretty good shape.
Swamp cooler pads
sprayed with vinegar
What else did I do to
prepare for winter? I placed weather stripping
on my doors.
See how I did this here...
Spring update - May
El Paso was starting to have a few more 90+ degree
days, so it was time to take the cooler out of
Before climbing up on the roof, I reattached the
copper tubing to the water supply. I then
carried all my tools and my cooler pads up to the
We have had several days over the last few months
where we had bad dusty wind storms. I expected
to find a layer of dust all over the inside of the
cooler. I was pleasantly surprised to discover
that I did not. The plastic bag taped
over the cooler pad metal panel (the one with the
holes) and the cover over the whole cooler, did the
trick. I had no cleaning to do.
I took the cooler pads out of the two bags I had
stored them in. Of note, I tried something
with the pads. When I packed them away, I
pored a couple tablespoons of Downy Unstopables
Laundry Scent Boosters into the bags. I
wanted to see if this would change the cooler pad
odor to something more pleasant when the pads were
put back in. It did. I now have the
pleasant smell of "Lush" blowing on me. I only
expect this to last for a day or so. I guess you
could sprinkle some of it in the water reservoir,
but you would have to do this every few days.
The only thing I might have to replace, is the water
shut off valve that is attached to the float.
I bent the float down so it would cut off sooner but
the valve feels like it will go soon. My next
trip to the hardware store, I will pick up one.
I just have to watch for water coming off the roof.
For now, I have to make sure I cut off the
water when I turn off the cooler.
See float valve
replacement and other cooler maintenance on this