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Emerson filter driers & moisture indicators

Hi wallies,

I have been particular to purchase Emersons EK lineup of filter driers and the HMI moisture indicators.
I was sold on the filter driers after watching a demonstration how they dont let filtered media past when the get vibrations from a compressor start up, etc.
The HMI sight glass moisture indicators supposedly show lower percentages of moisture then the competition.

Can anyone confirm the above statements before I go stock up? The local stores dont always seem to have these two products.

Happy HVAC'ing!


  • Techman
    Techman Member Posts: 2,144
    edited May 2015
    Happy HVACR'ing to you.
    The Alco/Emerson SGMI,is slightly more sensitive than the Sporlan/Parker, but we are talking only just a little. 75-80 PPM vs around 100 PPM or so. Go w/ the SAE(flare) its easier to replace the FD and SGMI ,if needed.
    I like both brands, but, IF/when there is a "comp burn out" w/ Acids, the acid breaks down the varnish on the comp motor windings and the varnish coats the yellow/green SGMI rendering it useless(depending) which means the SGMI should be replaced along w/ the comp. The yellow/green MI is a "salt derivative tablet" and the Alco SGMI is a "ceramic derivative tablet" and acid does not adhere to the ceramic tablet.
    If there is ANY CHANCE of acid in the system use the "HH" version of the FD , the "HH" is for neutralizing Hydrochloric and Hydrofloric acids.

    And it can take up to 24 hrs of running time for the SGMI to show its true color. I run across lots and lots of systems that need a 2nd and/or a 3rd FD change out. It is encouraged to go up a size or two w/ the FD. If there was an EK 163 (16 cu.in.)SAE FD you can go up to an EK-303(30 cu.in.)
  • NYplumber
    NYplumber Member Posts: 503
    Thanks for the reply.
  • Techman
    Techman Member Posts: 2,144
    On a 2t AC I removed an 083 FD , put in a Sporlan C303-HH w/ SGMI and today I changed the FD a 2nd time, and w/ the MI showing a very, very light green mixed w/ a wonderful hint of yellow I think I might have to change the drier a 3rd time.