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Jell substance in bottom of hot water heater

WojoWojo Member Posts: 7
I am a plumber and work in the Chicago suburbs, almost every town has Lake Michigan water, I have noticed when I drain and clean out the bottom of the 100 gallon hot water heaters with my arm in the clean out whole there is very little mineral debris but a lot of this blue/grey jell substance. Everyone I have asked to explain what this is gives me a different answer, bacteria, diptube resin, byproduct of all the chemicals added to the water, etc.. Can anyone out there give me a firm answer as to what this jell stuff is?  Thanks in advance, Mark


  • Steve WhitbeckSteve Whitbeck Member Posts: 669

    Could it be resin from the water softener?
  • WojoWojo Member Posts: 7

    Lake Michigan water tends to be soft by nature and it is rare to find softners anymore. The job in question does not have a softner.
  • mark schofieldmark schofield Member Posts: 140
    gel in tank

    I found a similar situation. I'm using a 50 gallon Whirlpool electric water heater as a solar storage tank for DHW. The electric elements are not hooked up. The tank temperature gets to about 150 degrees during a sunny summer day. Town water. Plummed with copper. 
  • Jim BennettJim Bennett Member Posts: 607
    Blue Goo.....

    Try posting the question here.

    My guess is it is dissolved solids in the water coming out of solution.

    Good luck,

    Jim Bennett
  • Mark EathertonMark Eatherton Member Posts: 5,584
    edited October 2010
    This is the reason I refused do ever to a direct potable water heating RFH system...

    I had 3/4" poly suitelene in between the floor joists of my home, connected to a 40 gallon gas fired energy hog. It never really worked other than knocking the chill off of the floor. When it came time to put a real heating system in with aluminum extruded plates, I cut the 3/4" ploy out and a bluish green slime came rolling out of the pipe. Almost looked flourescent. My wife works for the water company here in town, and I bagged some samples of the goo and sent it to work to be looked at in their lab. They said it was a by product of the magnesium anode and the alum and other chemicals in the water. They said it was also harboring naturally occurring bacteria.

    Dave Yates later introduced me to some terms that caused the hair to stand up on the back of my neck, like pipe slime and legionella. Both found on the insides of our potable water pipes.

    I decided at THAT point, that I NEVER EVER wanted to expose my customers to the potential of un-necessary exposure to this deadly disease and haven't installed one since.

    Bad enough that it can survive in a regular plumbing system, much less one with ALL the IDEALS it needs to flourish.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • WojoWojo Member Posts: 7

    Thanks ME for your response. You confirmed what I thought it was, byproducts from added chemicals in the water and bacteria. SCARY isn't it? Wojo
  • JackJack Member Posts: 941
    This is a characteristic

    of a "Storage" tank with so little velocity of flow that it cannot flush itself out. Perhaps this is strong point in support of tankless water heaters.
  • Mark EathertonMark Eatherton Member Posts: 5,584
    Yeah, except...

    People are unwilling to wait for their 1 man, three woman Jacuzzi tubs to fill with hot water. (Major dump loads). 120 gallon fill load divided by 3 GPM = 40 minutes. They want it filled NOW!!!

    In most cases, there is not enough fuel line capacity or upfront money to handle the dump load needs of these monstrocities, hence buffer tanks. They are a fact of life.

    One way to avoid the anode slime is to not use a tank that requires an anode (all stainless steel). But you will still end up with plumbing slime in the system. It is unavoidable as long as you are using water.

    You will even have plumbing slime in a system that uses a tankless heater. Just probably not within the heat source.

    Just sayin'...

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
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