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A job well done….. Almost
This tip was written by HVAC Applications and Technical Specialist Dakota Brown. Thanks, Dakota!
As a technician, it was always the same old story:
Are you done yet?
There was always pressure from the office—either from the dispatcher, service manager, or project manager—to get the job done and get it done quickly.
When I became an estimator and project manager at the company I worked for, I tried not to fall into the trap of pressuring the technicians (my former brothers-in-arms) to get the job done quickly by cutting corners, but I’m sure I fell victim to that mentality a time or two.
Now that I work for a distributor and am doing technical support, including start-ups, I can look at one of the biggest problems facing contractors more objectively. You all know what that problem is at this point, or at least you should.
We all talk about being thorough on service calls to prevent those dreaded callbacks. But what about callbacks on installs? We all like to complain about [insert brand here] and how their equipment stinks, but we all know that most issues with new equipment come from a bad install or, worse yet, a bad start-up. (GASP!)
“But I am always thorough on my start-ups!”
We've all gotten the call asking if we are done yet. Or, if we are coming home! We start to cut some corners and neglect to check gas pressure (I’m sure it’s fine) or airflow (I hear the fan running) before we pack up.
75% of the service calls I get on new equipment come from bad start-ups. Even when a contractor does the best install possible, they can blow it right at the end with a bad start-up.
That is why I say, “Almost.”
I liken it to a race. Nothing drives me nuts while watching a race or any other sporting event more than seeing someone pull up at the last minute, right before the finish line.
Run through the finish, don’t pull up at the end.
Time and time again, I see a good install go bad. So, let’s talk about a few key points.
- Check your voltages on a 208/230-volt unit. Most RTUs and splits that are dual voltage have multiple taps on the low voltage transformer, and if you don’t have the incoming voltage tapped right, you won’t get proper outgoing voltage.
- Make sure your trap has a large enough drop to prevent condensate from being sucked back through. Inspect the drainage while it's running.
- Check the phasing, seriously. It is simple enough to do beforehand with a phase rotation meter. Keep in mind that VFDs can correct phasing, so just because your condenser fans or blower run in the right direction, that doesn't mean the phase direction is correct if there is a VFD driving the motors.
- If your unit has a smart control board (I’m looking at you, York), make sure you configure the board to reflect what you just installed.
- Check your economizer in all modes.
- Airflow, airflow, airflow. This is the biggest one, really. I mainly work with York these days, and they have what is called a dry coil pressure drop in their manuals. Using some ports built into the unit and a manometer with some metal tubing, you can get the static pressure drop across the coil. This allows you to estimate airflow moving through the unit. It is so simple, but a lot of people don’t do it. I understand this is just a starting point, but we don’t live in a perfect world, and not everyone has an in-duct anemometer.
- Owner training!!!!! Teach the end-user how to use their new equipment, educate them on maintenance requirements, tell them something!
A lot of issues can be solved by reading the install manual and filling out the start-up sheet that comes with the equipment. If you don’t have one with the equipment, make one.
We could go on and on with start-ups and proper start-up practices, and maybe we will, but for now, let's all try to remember that rushing off of the job to get to the next one will catch up with you and your reputation.