Using PEK with black iron
Howdy;
I’m having a garage/bedroom added to my 1930 house. The existing dwelling has a hotwater heating system that utilizes free-standing radiators. My contractor suggested using PEX to connect up the new radiators.
When I spoke to my HVAC guru he told me he thought that PEX allowed oxygen molecules to enter the hot water system, which, from a corrosion isue, would be bad news for the old “black iron” pipe. He suggests using copper tubing instead, because the tight floor joist spaciing makes black iron unfeasible.
The heating extension consists of adding two vintage 1920’s radiators in the new bedrooms. Connecting with the existing black iron supply line requires adding approx 60 ft of new distribution tubing.
The plumbing sub hired by the contractor to handle extension of the domestic water system knows nothing about the oxygen transfer issue. He also has very little experience with heating systems. Can somebody out there help?
Thanks in advance
Replies
You can inform your circle of contractors that the oxygen issue sprung its head in the 70's and was resolved shortly thereafter - in Europe that is...in North America we seem to like to repeat OPM (other peoples mistakes)...anyways to make a long story short PEX has been available with or without an air barrier since the late 70's early 80's. Regardless, your application is better suited to PEX-Al-PEX, which has considerably less expansion than PEX and is perfect for your application. Uponor Wirsbo's MultiCor is a good choice.
RBean
web: http://www.healthyheating.com
blog: http://wonderfulwombs.typepad.com
Dear RBean;
Thanks very much for your reply. This will help me a bunch with my project.
Best Regards,
ultimatewarmth