HVAC Equipment Start-Up

We are going to start a four part series on the procedures that need to be followed for effective equipment start-up after the installation is completed. The section will be as follows:

1 - Start-Up Procedures

2 - Test & Balance

3 - Commissioning

4 - Training & Documentation

Although the Start-up procedure is one of the most basic requirements of a new system, sometimes during the rush and excitement of installing a new system, small areas can be overlooked and can lead to early equipment failure.

Each piece of HVAC equipment has a checklist which has been provided by the equipment manufacturer. These must be not only followed, but in some cases initialed and date stamped, via fax or email, to start the warranty, no start-up, no warranty. With as tight as companies must be run in the current economic conditions, some companies are using this as a loop hole to get out of providing parts which for all intents and purposes should be covered. Some items covered in the checklist may seem obvious, but it is usually the "obvious" items which become overlooked.

Below is an example of just the requirements for the motor start-up, not even to mention the rest of the machine:

Compare the drive model number to what was ordered.

Be sure the following are for the same voltage: Drive, Power Line, Motor

Record the motor data: Voltage, Frequency, Full load current, Full load speed, Power

Check motor wiring

Verify appropriate short circuit protection is provided at the input of the drive.

Measure phase to phase line voltage and ensure measured voltage is within drive specification

Measure phase to ground voltage.

Drive mounting clearances observed.

Check all wiring connections are secure.

Each drive grounded individually, no daisy chain grounds.

Separated runs for input power, motor power, and control wiring.

Check the motor’s rotation from the drive.

Accelerate the motor to full speed and verify operation.

Ensure that the drive follows run/stop commands from the system.

As you can see from the above list for just one of the drive motors, there are a lot of check and balance to ensure the system is operating correctly. If a system is not operating correctly, then these problems can be caught early and correct before the lead to failure.

While some of this may look overwhelming, if you take your time and each item by itself, then there is no reason for this not to be done throughly and correctly. Make sure that if you are having a new system installed that you receive this paperwork from your contractor before signing off on a completed install.

Remember, a no mechanical system should ever be considered to be running unless it has gone through the start-up procedure. Thanks for reading, and we'll see ya on the roof!