HVAC Water Leak - Unit Icing, a Common Cause
This time of year in Southern California brings that fantastically mild weather which gets everyone out of their houses and into the cool sunshine. These are the days which make Los Angeles the place everyone wants to be. On such days I like to go hiking in the San Gabriel Mountains outside Pasadena, or drive down to Orange County to do a little shopping, or perhaps enjoy a day at the Getty Museum in Santa Monica, gazing out over West LA and Hollywood.
I would enjoy these days more if it weren't for those pesky emergency weekend calls from commercial clients. That is because, within the HVACR industry, this is also the time of year for the dreaded water leak call. Water leaks in air conditioning equipment typically take two forms: the first form is usually due to an overflowing drain pan which is typically caused by a plugged drain line. But it's the second form which we see the most this time of year. The call typically comes in as follows, "My air conditioner was working great yesterday now it is blowing hot air and dripping water on the sales floor". This description is the telltale sign of a unit "icing over".
Air conditioners have a condenser coil and an evaporator coil. The purpose of the evaporator coil is to extract heat from a space. The purpose of the condenser coil is to expel that heat to the atmosphere. Between the two coils a refrigerant transports that heat. Air conditioner systems are designed to exacting specifications and are delicately balanced between evaporator and condenser; the coils have to be the right size, the air flow has to be in the right amounts, the refrigerant has to be charged to specific amounts. If any part of the system gets off balance the unit operates inefficiently, or sometimes, too efficiently.