At a glance
- Refrigeration units that power building air-conditioning can be susceptible to damage from the elements
- Infrequent inspections can lead to serious corrosion and potential explosions
- Brokers need to ensure their customers make their units available for regular inspections
Air-conditioning units are part of a building’s design that are often taken for granted. As these units are found on rooftops, and are often overlooked, forgotten and rarely inspected, brokers need to warn customers that the result of doing nothing could cause injury, severe damage and higher operating costs.
“There was one incident where a liquid receiver on a self-contained refrigeration unit exploded during testing of the high pressure trips, injuring the service engineer,” says John McMullen, Chief Engineer at Zurich Engineering.
“After the initial investigation, it was found that the explosion was caused by excessive corrosion on the bottom of the vessel.
Common types of deterioration often found on refrigeration units include:
- Loosening of fasteners due to vibrations
- Impact damage
- Contamination ingress
- Vermin damage
“The corrosion got to a point that when the engineer was doing a pressure test, the section just ruptured,” says John. “The pressure vessel exploded with the force of a hand grenade, splitting the unit, tearing off components and exposing the electrics.”
The majority of these types of refrigeration units are found on top of buildings all over the country, where they are either used for chilling units or building air-conditioning units. During the summer, they are often working non-stop, but during the winter they are generally inactive and left exposed to the elements. It is during this time that the majority of damage can occur.
The need for regular inspections
“These units are often placed on rooftops for various reasons as they contain gas, including ammonia,” says John. “Inspections require specialist people, which can be a major issue and often the reason these incidents occur.
“Unless these units are annually inspected, serious incidents, such as an explosion can occur. For these types of units, it is essential that they get a regular inspection by a competent person.”
To make things easier for brokers’ customers, Zurich has a team of highly qualified engineers are trained to deal with every make and model.
“Our engineers are trained to look for defects or something that is deteriorating and is likely to cause harm to people,” says John. “We bring an expertise and knowledge, where we’d look at these conditions and assess the equipment safety and what needs to be replaced or repaired.
“For your customers, it’s simply a case of making the units available for inspection.”
While the engineer in this case was uninjured, an exploding refrigeration unit not only has the potential to damage inspectors, but also the building, other vital systems and injure passers-by on the street below.
It is for these potential reasons, which could lead to serious liability claims, as well as the potential for business interruption that could occur, that brokers need to emphasis the need for regular inspections of these refrigeration units to their customers.