Tag Archives: enthalpy

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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Subcooling Can Aid in Troubleshooting

Let’s take a trip back to the basics to understand subcooling in the first place. In a refrigeration cycle, the condenser converts a super-heated high pressure gas into a high pressure liquid so it can be used by the evaporator … Continue reading

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New Honeywell Economizer Controls – Part 2

So, now that you have read my last post and have an “overview” of the new economizer control, we can get into the nitty-gritty of how to install and set-up, and diagnose the new economizer. The installation part is easy. The … Continue reading

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New Honeywell Economizer Controls

Spring is in the air (but we still have some snow too in the north central region) and as our thoughts turn to COOLING, we need to look at the ECONOMIZER.  Economizers still are the most misunderstood, misdiagnosed, most often … 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  Not that the information on the old controls is obsolete … Continue reading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 3

If you have been following my last two posts, by now you should understand what an economizer is; how it works; and how to properly set it up. Now, as promised, we’ll get into troubleshooting the economizer and its various … 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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