Air Conditioner Wet Switch Saves Day!

Magic Touch Mechanical includes an air conditioner wet switch in every applicable HVAC install we complete. Also known as an emergency drain switch or condensate drain switch, these little devices are worth every penny.


This Air Conditioner Wet Switch Alerted Me of a Roof Leak

air conditioner drain switchCall it luck, call it good karma coming back; my air conditioner wet switch warned me of a roof leak!

An air conditioner wet switch is designed to prevent ceiling and home damage in the case of a clog. If an air conditioner’s condensate drain line backs up, the wet switch turns the unit off immediately. The idea is to prevent any further home damage caused by water leaking on the ceiling and down walls.

With monsoon in full swing, we’ve been getting a lot of hard rain in the Phoenix, AZ area this year. Last week in the middle of a downpour, I noticed one of my air conditioning systems had stopped working. The message on my Lennox S30 thermostat read “Communication Error” and to, “Call Magic Touch Mechanical,” in this case … myself!

I noticed the red light on my air conditioner wet switch the moment I climbed into my attic. However, it wasn’t my condensate line that was clogged – it was a roof leak in a very fortunate spot. The leak just happened to be right above one of my air handlers and dripped right into the drain pan.

I say fortunate, as had the leak been even one foot over, it would’ve caused ceiling damage before I noticed. I’ve already scheduled my roof repair and thanks to my air conditioner wet switch, my home wasn’t damaged.


How an Air Conditioner Wet Switch Works

air conditioner wet switchThere are several types of air conditioner wet switches, emergency drain switches, and condensate float switches on the market today. Some are designed to be installed in the drain line itself, while others attach to the side of an emergency drain pan.

For attic installations, we (Magic Touch Mechanical) prefer to use the ‘hockey puck’ style air conditioner wet switch. We’ve found this to be the most reliable of all the designs when the air handler is in the attic. This type of wet switch sits right inside the emergency drain pan, also known as a secondary pan.

The hockey puck wet switch has a felt-like material on the bottom which is extremely absorbent and sensitive to moisture. When the wet switch senses even the slightest bit of moisture it turns off the AC unit power immediately. Only manually resetting the air conditioner wet switch will allow the HVAC system to run again. This allows the service technician to diagnose the source of the moisture and make repairs before home damage can occur.


In-line Condensate Drain Switch

inline condensate drain shutoff switchFor air handlers and coils installed vertically in a garage or closet, a different type of wet switch is needed. These drain switches are installed in-line with the condensate drain line itself to detect a drain clog when it starts. Although they may not drip on the ceiling, clogs in a vertical air handler can cause a lot of damage. This is especially true in cases where the clog or leak goes undetected for some time.

Considering most vertical air handlers have open cavities below them for return air, slow leaks can easily go undetected. It is not unusual for our installation teams to find long-term water damage after removing old vertical air handlers. For this reason, Magic Touch always installs an emergency drain switch when replacing an HVAC system, both horizontal & vertical units.


Sheet Metal Platform Liners Help Too

Home builders keep costs down by ‘decking’ your air handler / furnace platform with drywall over plywood or OSB. If you’ve ever seen what happens to wet drywall, you know a metal deck makes a lot more sense. One ‘extra’ step we take when replacing a vertical unit is to cover the deck with sheet metal. This helps to protect your home even further in the case of a condensate leak or clogged drain line.


Wet Switches & Roof Leaks

Of course, my wet switch detecting a roof leak was simply a matter of pure luck. An air conditioner wet switch is not designed to detect roof leaks. That said, this is not the first time I’ve seen the switch alerting a homeowner of a roof leak. Over the past decade, I’ve probably heard about a wet switch saving the day at least a dozen times.

In my case, the roof was leaking from a cracked ridge tile. Water found its way down to the flue pipe connected to my furnace underneath the roof underlayment (tar paper). As luck would have it, the flue pipe sits right above the edge of the emergency drain pan. The water flowed down the side of the drain pipe and leaked right into the emergency drain pan.


Protect Your Home with an Air Conditioner Wet Switch

Don’t wait until you replace your home’s air conditioning & heating system to install an emergency drain switch. Old, new, horizontal, or vertical, there’s an aftermarket air conditioner wet switch or in line drain switch for your unit. Your local air conditioning company should know all about them and can install them relatively inexpensively. Let’s put it this way … it will cost a lot less than your homeowners insurance deductible will!

If you live in Mesa, Arizona, or any city within a 35-mile radius, contact Magic Touch Mechanical. Our expert service technicians are very familiar with all the different air conditioner wet switches and overflow protection devices.


You May Also Like:

Water Leaks – Pipe on the Side of My House is Leaking

Why is My Air Conditioner Leaking Water?

Air Conditioner Drain Leaks





about the author rich morgan


magic touch mechanical ac - there's magic in the air



Magic Touch Mechanical

942 West 1st Avenue
Mesa, AZ 85210
Phone: 4808558789

There's Magic in the Air!



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