This month’s troubleshooting situation involves an air-to-air, package unit heat pump that is approximately 8-years old, and the customer’s complaint is that, rather than providing cooling, it’s just blowing warm air.

Bob and Tim are going out to a new job. It’s an air cooled chiller on the rooftop of an office building. This is the first air cooled chiller that Tim has ever seen so Bob is going to have to describe the operation of the chiller to Tim.

The equipment in this month’s article is a two-stage air conditioning system. The operating conditions are high ambient, and the customer’s complaint is that there is no cooling.

Bob and Tim are at lunch and discussing the last service call that they had which was a spring start up on a 100 ton chiller. Tim has some questions about how a chiller operates and Bob is filling him in on some blank places that he has in his knowledge base.

In this troubleshooting situation, the equipment is a walk-in refrigeration system in a busy restaurant that has experienced a compressor failure…specifically a mechanical failure.

Bob and Tim are on their way to a spring start up for a chiller in an office building. It is a 100-ton water cooled reciprocating chiller with the chiller in the basement and the cooling tower on the roof.

In this troubleshooting situation you’re called out to a tavern to check on a beverage storage unit that, according to the complaint, is “not keeping things cool”.

Bob and Tim are discussing the job that they are about to start. They are at a residence and the system has a blown low-voltage fuse. Tim said, “Let’s just change the fuse and try it and see if the system will start up. The only thing it can do is blow another fuse."

This troubleshooting problem involves a 5-ton, R-22 rooftop air conditioning unit, and the customer’s complaint is that on days when the ambient temperature exceeds 90°F, the system doesn’t keep the store, which was recently remodeled, comfortable even though it seems to be running continuously.

Bob and Tim arrive at the jobsite of a new customer. The customer is the owner of a shopping center that has a branch post office as one of its tenants. The complaint has been that the system is not controlling the indoor temperature in the postal facility. Tim tells Bob as they are arriving that the service ticket says that they are to service a 20 ton split system that uses a hot water coil for heating and an air conditioning coil and condensing unit for cooling. They are to do routine maintenance on the entire system.