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Manometers

tommyoil
tommyoil Member Posts: 612
Can someone suggest a decent/durable manometer. Are they all pretty much the same?? I dont want junk. Thanks in advance for any help/suggestions.
Tommy

Comments

  • gerry gill
    gerry gill Member Posts: 3,078
    Richie brand,

    tube within a tube.
    gwgillplumbingandheating.com
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • bob_44
    bob_44 Member Posts: 112
    Dwyer

    I have a Dwyer slack tube manometer tha I bought 42 yrs. ago still works fine. Cheap, accurate. The only problem with water manometers is they freeze in your truck. bob
  • Boiler Guy
    Boiler Guy Member Posts: 585
    Fill them with widshield washer

    > I have a Dwyer slack tube manometer tha I bought

    > 42 yrs. ago still works fine. Cheap, accurate.

    > The only problem with water manometers is they

    > freeze in your truck. bob



  • Boiler Guy
    Boiler Guy Member Posts: 585
    Fill them

    with widshield washer antifreeze
  • Sweet_2
    Sweet_2 Member Posts: 143
    Digital, UEI

    But I found out that my Field Piece multi meter has manometer/static pressure adapter as well as other cool attachments. Nice addition.
  • Boiler Guy
    Boiler Guy Member Posts: 585
    Digital

    meters won't accurately work below zero F. However, being an enterprising outdoors kinda guy ..... I put my UEI in a mit with one of those hand warming packs and voila my meter is warm as toast.
  • Glenn Harrison_2
    Glenn Harrison_2 Member Posts: 845


    Inexpensive, Dwyer Model 1227 Combo Vertical and inclined manometer.

    Better quality, Dwyer Magneheilic gauge of the appropriate range. Unfotunatly this may require more than one gauge depending on pressures being read.

    Ultimate manometer Dwyer 477-FM series 0 to 19.99" range. Can also be purchased as a kit with a pitot tube, static pressure tips, and a air velocity calculator (slide rule).
  • Sweet_2
    Sweet_2 Member Posts: 143
    Maybe

    Dropping the digital meter in a vat of antifreeze would work as well?? Maybe in a zip loc bag?
  • Joe Bologna
    Joe Bologna Member Posts: 3
    You sure about that, Boiler guy?

    > with widshield washer antifreeze



  • will smith_2
    will smith_2 Member Posts: 49


    I've been using magnehelics ever since my first u-tube freeze-up. I carry a 0-5", a 0-10", and a Ritchie gage for 0-35". Perfect for checking gas pressures, static pressures, and for checking pressure switches.
  • bob_44
    bob_44 Member Posts: 112
    Windshield washer

    fluid wouldn't be accurate. different density.
  • testo

    I've been happy with my testo digital manometer. Easy to use and accurate.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • Boiler Guy
    Boiler Guy Member Posts: 585
    Bob

    According to my test procedure the difference is about .005"WC. Not enough to be a concern
  • Boiler Guy
    Boiler Guy Member Posts: 585
    Great tool

    I've got em too but kinda pricey for the average service tech. Also they DO NOT like being banged around in a service truck
  • Aidan (UK)
    Aidan (UK) Member Posts: 290
    antifreeze

    antifreeze

    Different density to water, will cause an error. I don't know how much of an error without looking up densities.

    PS Bob said it first & I didn't notice.
  • Aidan (UK)
    Aidan (UK) Member Posts: 290
    Yes, but

    But that gauge has a zero error of about 2.96" w.g.! ;-)
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,212


    Manometers- The only tool that will never lie.
  • Boiler Guy
    Boiler Guy Member Posts: 585
    Aidan

    Windshield Washer Afreeze is mostly water any way. Very little difference from straight water
  • Manometer is most

    accurate when used with only water.Do not leave water in the unit it will freeze. Fill it each time you are going to use it. My two plastic dwyer manometers (40 years old) have outlasted every magnehelic and other guage.

    As for using different fluids I ran tests when I was with the gas company and anything other than water or the fluid sent with the gauge is going to give you incorrect readings as the viscosity of other fluids is different than water. If I can find the test results in my library I will post them here.
  • Here are my test results

    ACCURACY OF PRESSURE READING

    OR

    YOU AND YOUR U GAUGE

    One of the most accurate and convenient means for measuring low-pressure is the Water Manometer (U Gauge). The pressure reading is stated in "inches of water column" (W.C.). The pressure in our low-pressure distribution system usually is set between 7 and 10 in. W.C.

    When checking or adjusting pressures in our low-pressure system, the Water Manometer is usually used. The accuracy of the reading taken is dependent on the fluid in the manometer. For example, if the pressure is to be stated in inches of water column (W.C.), water must be used as the fluid in the manometer. Different fluids or a combination of fluids will change the accuracy of the measurement.

    Testing was done to determine the effect of using different fluids in a manometer. With the known pressure source different fluids were used and measurements recorded.

    Materials Used

    1 Manometer, part No. 1225-12

    1 Sprague B3regulator 3/4" x 3/4", 1/8" orifice

    Tap water

    Alcohol

    Bristol chart ink (red) No. 382476-16-8

    Test Data

    SOURCE PRESSURE 7.0" W. C. for all testing.

    WITH JUST WATER pressure recorded 7.0 W.C.

    WITH ALCOHOL pressure recorded 8.7" W.C.

    WITH A MIX OF 1" Chart ink, 11" alcohol,

    pressure recorded 8.2" W.C.

    WITH A MIX 9" tap water, 6" Alcohol, 2" chart ink

    pressure recorded 7.2" W.C.

    So What Does This Mean?

    To be sure the measurement of pressure is correct when using a water manometer, the fluid in the manometer must be water or a fluid with the same specific gravity of water.
  • Boiler Guy
    Boiler Guy Member Posts: 585
    WW Anti freeze

    You posted:
    WITH A MIX 9" tap water, 6" Alcohol, 2" chart ink
    pressure recorded 7.2" W.C.
    Using -30F rated windshield washer antifreeze
    pressure recorded 7.05" W.C.
    Disclaimer: While the density of the product used may differ from one manufacturer to another, the product I used for MY TEST was extremely close to water density.
    For ABSOLUTE accuracy Tim you are TOTALLY correct

    This is exactly the same principle as using a meter ALWAYS CHECK AGAINST A KNOWN SOURCE BEFORE USING !
This discussion has been closed.