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draft simulator

Paul S_3
Paul S_3 Member Posts: 1,257
I just recently purchased the "draft simulator" by Fieldpiece. Its purpose is to test pressure switches. Has anyone used this tool? and is this the ONLY way to test pressure switches? Thanks Paul S
ASM Mechanical Company
Located in Staten Island NY
Servicing all 5 boroughs of NYC.
[email protected]


  • Brp814
    Brp814 Member Posts: 22
    Draft Simulator

    I purchased one back in the early fall. I have only used it a few times. It does work pretty good, but I don't 100% trust it. It may be my manometer, but I really have to get used to the tool, and what it does, before I will put my trust into it. As for other methods of testing pressure switches? The DDSM1 is the only one I know that will test them properly
  • Jim Davis_3
    Jim Davis_3 Member Posts: 578
    Draft Simulator

    The Draft Simulator is the best method to test and adjust pressure switches.  I am sure the dependability of your digital pressure gauge might has some bearing.  Draft switches are set for when they open not when they close.  The draft simulator allows you to adjust the pressure applied to the draft switch by hundreths of an inch and watch exactly when it opens and closes.  It allows everyone to carry universal pressure switches rather than different ones for every make of furnace. 

    Changing out pressure switches that aren't bad because we are guessing is very costly.  Not changing ones that are bad is just the same. 

    The draft simulator was invented by one of my contractor customers in Cincy.  Before they sold it to Field Piece we were selling them to our customers.  I was out with a commercial contractor a few years ago and he had made his own draft simulator using a large tank of Nitrogen gas and a gauge set.  Weighed about 70 pounds. 

    I would still be selling them if they hadn't been sold to Field Piece.
  • Brp814
    Brp814 Member Posts: 22
    New Manometer

    I purchased a new manometer the Fieldpiece SDMN5. The Draft Simulator works much better.
  • Spence
    Spence Member Posts: 316
    Pressure Switch Test

    You can inexpensively obtain vacuum hose sections and plastic barbed tees from an auto parts house, which will put your manometer in series with the switch and gas valve or inducer. Pull the factory hose off the switch so you're not cutting tubing that requires a coupling to reconnect. You can also check calibration by pinching the tubing and tubing condition at the same time.
  • Anthony D.
    Anthony D. Member Posts: 63
    adjustable draft pressure switches

    What range is acceptable for an adjustable pressure switch that would work for most furnace draft fans?

    Also, do you know of a universal dual pressure switch?
  • heatpro02920
    heatpro02920 Member Posts: 991
    I have a ddsm1

    I never use it {maybe once a year}, I just run the unit with the manometer hooked up, if I see it locks out and had enough pressure to close the switch and all the lines are clear then I will change the switch... I good manometer and multi meter are much more important than any fancy pump will ever be.. but we do love tools..
  • earl burnermann
    earl burnermann Member Posts: 126
    Draft Simulator

    I'd love to get my hands on one of those simulators. Probably the best way to make sure the pressure switch is working properly. Watched a video on them and it said to use the measurement on when the switch opens to test switches. One of the biggest benefits of this tool is that you can stock adjustable switches on your truck and set them to what you need on the job. No longer need to carry a variety of switches. Just make sure you note the iwc on the switch with a magic marker when you install it.
    If the women don't find you handsome, they should at least find you handy!