To get email notification when someone adds to a thread you're following, click on the star in the thread's header and it will turn yellow; click again to turn it off. To edit your profile, click on the gear.
The Wall has a powerful search engine that will go all the way back to 2002. Use "quotation marks" around multiple-word searches. RIGHT-CLICK on the results and choose Open Link In New Window so you'll be able to get back to your results. Happy searching!
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit

grit in system

I have a radiant heat system using 3/8" Onix tubing - ten 200' loops, single zone, currently fired by a Crown Bimini boiler. For the last seven years , whenever I've purged the system because of circulation problems I get a gritty substance in the water - it's mostly grey , white and tan with some magnetic particles . There's usually a couple teaspoons to a couple tablespoons per three gallons of water. So the questions are: What is this stuff? Where is it coming from? How can I stop it? Why me?


  • kcoppkcopp Member Posts: 2,522
    Pretty good....

    bet its Rubber. The Onix starts to break down... whatever you do NOT add gycol. That will kill the tubing. I would however flush it out , clean it w/ a good product and add a inhibitor. Rhomar has these products.
This discussion has been closed.


It looks like you're new here. If you want to get involved, click one of these buttons!