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Electronic Sight Glass

My questions are to do with an electronic sight glass that I have. But don't have an operators manual for. The clamp on sensors, how far should they be apart? And also in charging an AC system, should you always or usually have liquid after the condenser where you would be testing?  Somewhere it seems I heard that it is 'Ok' to have bubbles in the line where you would be testing for example in an automotive system with R134a?    Just tossing these questions out!    Thanks


  • JStarJStar Posts: 2,668Member
    You should...

    ...always have liquid from the condenser to the metering device. Sensing the temperature on the liquid line will tell you if the refrigerant is liquid or saturated. A subcooled refrigerant will always be cooler than the relative temperature on a P/T Chart. The chart is a reference to saturated temperatures. Read your pressure. Sense the line temperature. If the temperature is above what the pressure is, you have vapor in the line. And if the temperature is below that reference number, you have a subcooled liquid. Subcooling just ensures that there is a full line of liquid going to the indoor unit. Typically, bubbles in a sight glass means you don't have enough liquid in the line, putting you in a saturated state.

    I'm not familiar with your device. Hope that helps.
  • TechmanTechman Posts: 2,144Member
    electronic sightglass

    What brand  & mn# ? Also,98% of system are supposed to have a full liquid line going into the metering device.
  • RoosterRooster Posts: 2Member
    Name on tester

    All I can find on the tester is Sonic-Site. Patent 4138879  Runs with a nine volt battery. Seems to work but haven't used it much. Has two clamps to clamp on the line.  Anyone have one of these like or similar?   Thanks
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