Building Updates: Aging HVAC and Roofing Systems

October 31, 2017HVAC

As an insurance adjuster, it’s important to note that the primary loss driver in the HVAC equation is the air conditioning system, particularly roof-top units, which are especially vulnerable to damage and neglect.

Roof-top AC units, which are used to cool nearly half of all commercial floor space in the United States, need special care and maintenance to guard against damage caused by dust, debris and, in certain areas of the country, damage caused by hail.

An air conditioner is designed so that air can flow freely and smoothly over the fins and through the condenser coil. When the fins are distorted or damaged, air cannot flow easily to the coil. In cases of severe damage, the airflow to the coil may be blocked altogether. A few bent fins will not typically affect the AC unit, but when extensive fin damage reduces or blocks the air flow, the unit cannot operate efficiently. Over time, the damaged unit will function less efficiently, and may fail completely. Because the damaged unit must run for longer periods and at hotter temperatures to produce cool air to meet demand, the cost of operating and maintaining the damaged AC will rise over time.

Outdoor air conditioning units can be protected from hail damage with the installation of hail guards, also called hail shields, which are designed to protect the condenser coil from contact damage. The guards also protect against falling branches, storm-blown debris, and any casual contact damage, such as may occur during maintenance activities. Hail guards can also protect ground units from damage by weed-whackers, lawnmower discharge, balls, etc.

While hail guards can offer effective protection against hail and large airborne debris, some guards, especially those with small-gauge openings, may create new problems by restricting airflow, trapping and retaining organic matter such as seeds, especially cottonwood, dust, insects, leaves, thus blocking the required air flow to the condenser coils.

To address this concern, air intake filters are available that combine effective hail protection with air filtering technology. These products use materials specifically engineered to promote air flow, thus making them highly suitable for use on high-velocity and high-volume systems. (See Figure 2)







Adapted from an original article written by  S. Carl Morello for Insurance Journal.

Figure 1. Hail-Damaged AC Unit. Photo courtesy of CR Roberts Consulting Engineers.

Figure 2. Air Intake Filter with Hail Guard. Photo courtesy of Air Solution Company.