Submerged A/C Condenser Unit

On December 1, my neighbourhood experienced a flash flood that brought 50+ inches of water, destroying my car, flooding the basement and completely submerging my new A/C condenser unit for approx 2 hours. After the (muddy) water receded, the temperature dropped to well below freezing for a couple of days.

I’ve talked to my HVAC guy, who thinks that the unit should survive relatively unscathed.

I’m sure that some of the members have had experience with submerged units… any comments / suggestions?

Should I be doing something special when I start it up this season?

Thanks in advance.

As a guess I would rinse the fins gently with water (and a garden hose?) and start it up before the season starts to see if it runs OK (assuming the temperature is not too cold). (1/23rd of an inch) 0.042 inches of dirt on an air conditioning coil can reduce it’s efficiency by 21%. But be gentle. I’m sure the HVAC guy would have stung you with a bill if there was the smallest chance of a problem.

What about the unit on the inside of the house (I assume in the basement). Was this OK? I hate to think what a flood would do to my little condensate pump that sits just above the basement floor. The poor little thing would probably try to act like a sump pump, at 76 gallons per hour! If your condensate line discharges outside, you may want to flush this through with water to make sure it is not muddied up from the flood.

I would flush the fins and motor, (and any electronics) with water, to clean any muck from the entire unit. Since this is a sealed unit, it should not cause a major issue, in my opinion. Of course, you might want to shut off the breakers first.:stuck_out_tongue:

Speaking as a retired HVac person I would find me another HVAC person any time the electronics, the condenser fan motor, the holding coils on the contactor or any other open type wiring on the unit will probally retain enough moisture to cause you problems. If I had insurance I would want all of the open electrical controls and or devices changed out. I would recommend turning on the disconnect with a long wooden pole.:slight_smile: Once in my other life observed a 750 ton centrifugal chiller 1240 volts; submerge all of the controls and the purge pump motor in a flooded basement, bad news.

I ditto what Charlie said,

Now is the time to use that parts warranty that came with your equipment. Be wary I have noticed a trend of insurance companies going belly up after natural disaters. I have had one of the properties I own in Charleston, SC drop by an insurance company simply because the wind zone changed.

Most people in these parts (myself included) don’t carry flood insurance… because it just doesn’t happen that often, and it’s very expensive… so… any repairs are on my nickel.

I’ll try the garden hose flush (electricity disabled) and hope for the best. I’m assuming that the manufacturers warranty will still apply for any parts that I need replaced. Hopefully I’ll only be paying for the labor to replace the effected parts.

One more question. The flood water undermined the 24" x 24" paving stone that the unit sits on, and as a result it tilts down about 10 degrees on one side. What is the maximum tolerance for “off level”?

Thanks again.

Joe I don’t believe I have every considered the question of tolerance for level. My install jobs were always level. Never really thought about it. A hermetically sealed compressor has a level of oil in the crankcase that is suppose to be reasonably level. Personally I would be more concerned that someone observing the unit out of level and thinking that I installed it that way(cosmetically pleasing) Why can you not just level the pad???

Manufacturer’s parts warranty will not cover fire, floods or even the home owner or others crashing an auto into the condensing unit. Am sure you meant to say homeowner’s flood insurance.

The major problem I see (and I go along with Charlie) is that most new equipment have single poll magnetic contactor’s that only break one leg of electrical power to the unit. So, in light of this all of your electronics which was below water may have been damaged through short circuit to the water.

If your HVAC guy thinks there’s nothing wrong with it being underwater, I would have him do the startup.

I have seen many motors that have been under water for a long time and they have worked well after a flood provided they are completely dried before power is restored.
They must be completely dried after the flood before any power is restored . .
If this has to be done at home wash softly and well .
I would put on a couple of heat lamps and make sure the equipment gets very warm for a few days.
I have no idea on the electronics but what have you got to lose by doing the same thing Good luck and please keep us posted .
Remember the left hand rule for all disconects.

Roy Cooke

Thanks to all for their advice and suggestions… great information.

Charley - My plan is to level the unit again, but I’m concerned about damaging the refrigerant lines - just how flexible are they?

I’ve attached a picture for your reference - you can see how it tilts towards the house now.

Yes, all is not lost.

Most of this equipment can be washed off as long as you don’t turn it back on until is completely dry.

However, some damage could occur from having 120 V passing through the components while underwater, so stand back when you turn it on!

Sorry - can’t get the picture to upload.

Most residential refrigerant piping is soft drawn copper and can be bent easily as long as you don’t allow it to crimp.

Thats where the left hand rule comes into play.

Roy Cooke

How about posting that left-hand rule here!?

Posted before.
Years ago when I was an apprentice I was taught to always use the left hand to throw all disconnects.
Twice during my life this has saved me from serious injury.
If their is a serious fault in equipment and the disconnect explodes the cover goes over you left shoulder and not into your face.
Seen once never forgotten when all that is left from 600 volt fuses but the brass ends you gain a lot of respect for electricity real fast.
Roy Cooke

OK I think that the picture is attached now.

Thanks to mlarson for the link to the tutorial.

Web Web Tilting AC.jpg

You have all kinds of room to move that unit back. The line set is high so you can raise that thing a foot if you wanted.

Why not just lower the high side of the pad ???
THat way no jacking or anything just dig out the dirt and it will come down on it’s own.