Tag Archives: IAQ

Flood Damaged HVAC Equipment

The South Central, Midwest, and the Northeast have seen record rainfall in the last month and, especially, the last couple of days.  Rivers are over flood stage.  Sewer systems could not keep up with all the rain and sewers backed … Continue reading

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Air Conditioning and Humidity Control

I recently received this question from one of this site’s readers: “Is it a good or bad idea to leave the ahu fan on in a commercial system?This facility is a bank and is experiencing a higher than normal moisture … Continue reading

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More Info on ECM Motors

The other day, a service tech called and wanted to make sure that he was making a COMPLETE diagnostic of an ECM motor that was not working.  He had checked out the motor with his GE TechMATE Pro and found … Continue reading

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New Economizer Control

Just when you think you can’t learn anything new about economizers,  Honeywell is going to phase out all of those controls and is introducing a new control — the W7220.  Not that the information on the old controls is obsolete … Continue reading

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Economizers –Revisited Part 4

In this fourth and final post on Economizers, I’ll try to go through troubleshooting the mod motor and the logic module.  In the last post, we went over the enthalpy sensors and discharge/mixed air sensors diagnostics.  Now we begin  with the … Continue reading

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Economizers — Revisited Part 2

In my last post, I explained how economizers should work and the importance of installing a 2-stage thermostat on ALL economizer applications.  I also stated  that — Economizers are the most mis-understood, mis-diagnosed, and most often gutted control system on … Continue reading

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