Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 ahowell 95
6 KnowledgeBase 95
7 skbloom 80
8 Guest_98024861 70
9 Guest_9311297 70
10 Guest_9400529 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 9/7/2011

How often do overflow switches fail on air conditioner pans?

I have had the switches fail twice in an attic unit and had lots of water damage both times. The contractor says it is not his fault because it was a part failure. The switch was manufactured by Aqua Guard.

Do you have the same question? Follow this Question

3 Answers


The Aqua Guard Float switches are very reliable. We use them on all of our systems in the attic. We occasionally find that they fail, maybe 1 out of 1,000. In all cases that we have come across when they fail they actually turn the system off, we have never had an issue where they completely failed to sense water. I would also verify that the swith is A) Mounted properly on the pan (vertically) and B) it is wired into the red wire properly to insure that the system will completly shutdown and alert you that something is wrong (your system won't do anything).

If you were my customer and this happened twice I would run 2 switches in tandem wired in series, so that if one failed the other would sense water in the pan. Another alternative is to install an EZ Trap with a float switch. This will sense that the Primary drain is blocked and shut the system down before the water even collects in the overflow pan.

I hope this helps!

Justin Zocchi

NATE certified Technician

Race City Heating & Air,LLC

Mooresville, NC

Answered 9 years ago by Justin Z


float switches are very simple if it fail once but if it fails twice replace it it is made to stop your system to avoid any water damage it is easy to replace it is a two wire set up buy one at your local supply store clip it on the pan and go wire for wire you do not need to open up your system it is all external. check it by running your system and lifting up the float if it shuts up your system you are good if it does not it was wired up wrong from the get go call a tec. to resolve your problerm correctly. all float switches are basely the same they are not expensive just the tec if you need one

Ray Gonzalez from koolray heating and air

clarksville, ten. 37042


Answered 9 years ago by Raymond Gonzalez


I beg to differ about the contractor being at fault! His installation is the problem. What bothers me the most is that no one addressed this in the previous post. First, it is highly unlikely that two "AquaGuard" switches in a row failed. It is more likely that he either installed the switch incorrectly, the secondary drain-pan (it sets just below the indoor evap. coil and air-handler unit) may have overflowed due to improper leveling, the condensate drain-line may have been ineffective due to poor design, or you had excessive ice build-up on the evaporator coil due to poor airflow and crappy duct design through your ductwork system. The ice build-up would create excessive condensate that could either overflow the drain-pan or bypass it all together. Secondly, the contractor should have been aware of any potential operating issues. A more qualified contractor would have investigated any potential problems and reviewed them with you prior to installing the equipment. Please review my videos detailing installation jobs dealing with these same issues. It will enlighten you and possibly help you to determine what the actual problem is/was with your attic air-handler. I suspect you had a poorly installed system due to the fact that a properly installed air-handler unit should never spill over into the secondary drain-pan. Its [secondary drain-pan] function is to protect your house only in the event that a problem arises. It's not meant to function on day to day bases. If your secondary drain-pan constantly has condensate water in it, your system is not functioning correctly!

You can also checkout my website under the air-balancing page. It's very informative about air-flow and how it affects your HVAC equipment.


Answered 9 years ago by Stans HVAC

Related Questions

Terms Of Use
Privacy Policy