#TXV

Tech Tips:

What to Check Before Condemning the TXV
I just noticed this portion of the Carrier air handler sticker for the first time the other day. I'm like most techs; it's easy for us to ignore the great info posted right in front of us on the data tag. That's because so many of the notices contain info we are used to seeing. […]
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How I Failed to Re-diagnose: The Lesson I Learned
This is the tale of how I found myself stuck on a service call for over 12 hours on a weekend due to my failure to re-diagnose an issue. I was working for a service company that had many accounts with local gas stations. These were large customers, and we did everything we could to […]
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Balanced Port TXV
  I walked into a supply house the other day and looked at a “universal” expansion valve on the shelf. The friendly guy behind the counter saw me and walked over. After saying hello, he said: “That's a great valve; it's even balanced port.” Now, I am a bit of a troublemaker. I should have […]
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What is a HSO (non-bleed) TXV/TEV?
There is a lot of misunderstanding about the HSO (hard shut-off) or “non-bleed” TXV (thermostat expansion valve) and what makes it shut off, why it exists, and how it “magically” opens. Once you understand the forces inside the valve, it is quite simple, obvious, and sadly devoid of any magic. The Three Forces  The TXV […]
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How to Diagnose a TXV Failure
There has been much written and many jokes made about the misdiagnosis of TXV (thermostatic expansion valves), and rightly so. This article will cut straight to the point to help those of you who may still need a bit of clarification, and hopefully, we will save the lives of a few TXVs and the pocketbooks […]
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Market Refrigeration TXV Adjustment
This quick article was written by market refrigeration tech Clayton Peeples. Thanks, Clayton! Adjusting the TXV should be done last after checking all other causes of the case being warm or floodback on the rack. TXVs very rarely go bad; generally, it's a dirty screen or a failed powerhead, both of which can be addressed […]
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TXV Power Element of Surprise
The TXV powerhead or power element is the part of the valve that sits on top of the valve to which the sensing bulb is attached. The powerhead provides the opening force for the valve by translating force from the bulb to a diaphragm in the element that forces the valve open. The sensing bulb […]
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Replacing a Piston w/ TXV and Evacuation
We get a lot of questions about both evacuation procedure and TXVs so last week we produced videos on both topics, including: • Before and after testing of piston vs. TXV • Using the Bluvac Measurequick app • Use of core remover tools for evacuation • Flowing nitrogen • creating an external equalizer port and […]
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