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how do you troubleshoot a high pressure switch with automatic reset

I'm having trouble figuring out how to troubleshoot one of these without it being in the system.


  • icesailor
    icesailor Member Posts: 7,265
    What does it do wrong? What kind of switch is it and what is the application?
  • brianthethird
    brianthethird Member Posts: 3
    Well I'm more so looking for a broad answer instead of a specific one... excuse my inexperience but this is for an assignment.. I'm given a high pressure switch (just the component) and asked to troubleshoot it. So make sure the switch opens and closes at the cut-in and cut-out pressures.. so I assume I'll need to check for continuity through the switch but how am I supposed to get high pressures to go through the component?
  • Abracadabra
    Abracadabra Member Posts: 1,948
    what kind of pressures are we talking about?
  • brianthethird
    brianthethird Member Posts: 3
    Head pressure of a heat pump cycle
  • John Mills_5
    John Mills_5 Member Posts: 935
    Well, create high pressure. If you are in cooling mode, yank the outdoor fan. If in heating mode, yank the indoor blower. Won't take long for the pressure to get up to a high level that should trip the switch if it is behaving. If not, the bypass on the compressor should open and it will let you know it ain't happy!
  • Ironman
    Ironman Member Posts: 6,868
    As already stated, it should have been tested while still on the unit by making the head pressure rise to the setting of the control.
    Doing it off of the unit (which makes no sense), would require you connecting it to a high enough pressure source such as a nitrogen bottle with an accurate gauge and slowly raising the pressure to the setting of the switch to see if it opens.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.