Drip Loops and Straws

Many of us are aware that X13 and Fully variable motor failure has peaked over the last few years, and I'm sure there are multiple reasons for that. One of the reasons is fairly simple and can be traced back to two simple installation and service practices that can be easily implemented.

  1. Seal all air handler/furnace/coil penetrations
  2. Use drip loops on wires entering the motor


Eliminating “Straws”

Straws are openings in the cabinet that are unsealed and “suck” moisture into the system. That moisture can cause condensation on the interior surfaces. These “straws” can be copper penetrations, drain port openings, and electrical penetrations.

The presence of straws is a bigger factor on fan coil systems and package units than on furnace/coil systems. That's because, in a fan coil or package unit, warm/moist air can more easily be drawn in after the coil and before the blower.

When unconditioned air enters into the system due to these penetrations, it can cause mold, short circuits, and corrosion. This moisture can also gather on wires and drip into electrical connections, causing issues with motors and control panels.

Make sure to seal any penetrations into the conditioned compartments of equipment with proper rubber grommets or, in some cases, silicone or thumb gum can be used.


Wire Drip Loops 

Anytime a wire enters a plug, board, or motor, it is best to either locate the connection facing down to prevent water from entering or make a drip loop before the connection point. That allows moisture to drip off of the wire before entering the connector or device.

These issues have been identified as causes of X13 and ECM motor failure, and checking these two areas can be very helpful in preventing future failure.

—Bryan

  

Related Tech Tips

Setting Sights on Safety: Eye/Face Risks and PPE
DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source. Although we primarily work with our hands, our eyes are one of our most valuable assets in the industry. After all, […]
Read more
Double Lugging, A Common Mistake
Connecting more than one wire on or under a single lug or connection point is called “double lugging,” and it is ONLY allowed in line voltage wiring under one condition, according to NEC 110.14: If the terminal, lug, or connector is specifically rated for more than one wire In the case of a conductor splice, […]
Read more
How to Set a Charge by Superheat
So many techs are OBSESSED with how to set a charge rather than understanding all of the readings, specs, and system conditions that go into optimum system performance. Before “setting the charge,” I suggest (nay, I REQUIRE) that you do a full visual inspection of the system, have an understanding of the initial factory charge […]
Read more

One response to “Drip Loops and Straws”

  1. Thanks for the tip. This is going to save us a lot of problems. I’ve already sharing it! I been pulling my hair, now it makes sense. I’ve mentioned it at work about moisture in air handler. They looked at me crazy, lol. Can’t wait to to rub it in their faces. Thanks, Angel.

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

loading

To continue you need to agree to our terms.

The HVAC School site, podcast and daily tech tips
Made possible by Generous support from