For some of you, this article will be a review to refresh your memory about the importance of "safety first." For those of you starting out as technicians, it could keep you from serious injury - or worse - out in the field.

Although some technicians are unsure of its operation and many customers have no clue it is even there - much less what it does - the economizer continues to fight a lonely battle for recognition as it saves building owners money on utility bills.

This article explores how a restricted metering device will affect system performance and efficiency. The system is a commercial refrigeration system with a thermostatic expansion valve (TXV) as the metering device.

In this installment of the series, Bob is called to do a tuneup on an oil boiler. When he starts it up, he finds too much heat is going up the flue. Btu Buddy helps him in narrowing down a solution.

Spending as little as 10 minutes discussing proper humidifier operation and troubleshooting tips with the homeowner at the time of installation could eliminate future callbacks.

In this edition of the Btu Buddy series, Bob encounters a furnace that is not drafting like it should. Btu Buddy helps him determine the problem and make recommendations to the homeowner.

This application note was written to provide you with an understanding of the basic principles of fossil fuel heating systems and how to troubleshoot these systems using thermometers, digital multimeters, pressure/vacuum modules, and other accessories.

A feature story in the Dec. 1, 2003, issue of The News dealt with air conditioning system diagnosis. That article focused on airflow problems. This article concentrates on refrigerant flow problems.

Pulling a good vacuum before charging a new system with refrigerant or after a repair is essential for the proper operation of an air conditioning system. In addition to the vacuum pump, a micron gauge is an essential tool.

With one end of the building cool and one end warm, Bob and Btu Buddy discover an airflow problem. Find out how they track down the problem and repair the system.