domestic hot water and heating piping

Asked December 26, 2014, 1:43 AM EST

We are installing 3" schedule 40 black steel pipe in our domestic and hot water mechanical rooms. My question is can we use threaded pipe with the proper unions, tee"s etc. Or must we use welded flanges? 150 psi pressure and 180° temp. Nothing high pressure or high temperature.

Can you please provide an OMA standard that proves we do n9t have to use welded flanges?

Thank you very much.

Outside United States

1 Response

I'm sorry that your question is outside my expertise as an Extension housing specialist. Still, connection requirements vary according to local code, not just the national standards, so it may be best to check with your local building code official. Also, national codes can be viewed online for free a few layers deep into