Tag Archives: meters

Compressor Electrical Diagnostics — Revisited

In reviewing posts from time to time that have the most views i feel it is a good thing to bring back a post that was previously written.  The following was originally written back in 2011 but there have been … Continue reading

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Spring Cleaning — Part 1

Well, here it is March 3 which places us in meteorological SPRING. (And, for those in the U.S., don’t forget that Day-light Savings Time starts THIS WEEKEND ). I know that those of us up north and out east are still dealing with … Continue reading

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Heating Season — Air Flow

In the last post we discussed temperature rise and how to check that.We discussed how this affects the proper operation of a furnace and keeps it from operating too hot and cycling on the limit control. We talked about adjusting fan speed  to … Continue reading

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Heating Season — Flame Rectification

Today’s units react to unsafe conditions in less than a second. This is accomplished through the use of “computerized control modules” and a flame sensing control system known as flame rectification. The safety used in today’s furnaces that accomplishes flame rectification is … Continue reading

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Hot Surface Igniters

To start this post, let’s answer the question, What is a Hot Surface Igniter? The hot surface igniter, or glow bar as it is commonly referred to, is a device that lights the burners in your furnace. Just as you used … Continue reading

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“Can’t See The Forest for The Trees”

Of course, the title of this post is a very old saying but I felt is was appropriate here.  Why did I choose this as the title — because the meaning is: If you can’t see the forest for the … Continue reading

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No Cooling Due to Heating Lockout?

Well, it looks like spring is finally here in the Midwest (better late than never :>)).  It is cool /cold at night and may require the heat to turn on and then turns nice / warm during the day requiring the … Continue reading

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4 Bad Boards in 4 Days! (a new record)

Yes, the title of this post is exactly what a contractor had done on a unit — replaced 4 boards in 4 days. I finally got the call from the owner of the building, who was very frustrated and upset … Continue reading

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Compressor Locked Rotor Diagnostic

Each year, the compressor manufacturer’s receive numerous field returned compressors that apparently have failed. A significant number of these, believe it or not, are still in good working order.  A high percentage of these good compressors are single phase compressors condemned … Continue reading

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3 Bad Boards in 3 Months?

What do you think the odds are of a new roof top unit going through 3 control boards in just 3 months since the unit was installed? And, if this truly was the case, don’t you think some one would … Continue reading

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