Heating not working in the floor where the distribution system was changed

mbyregow

The distribution circuit system was replaced after a leak was found at one of the joints in the old system. Before removing the old system, the entire circuit was flushed and then refilled once the new system was installed.

However, the floor where the new distribution system was installed isn’t getting any hot water circulation. It's as if the boiler can't detect any radiators on that floor. I've already tried re-flushing and refilling the system, and bled all the radiators and the boiler, but the issue persists.

The other floor, where the distribution system wasn’t changed, is functioning normally, and all the radiators there heat up properly. I'm a bit stumped on what else to try and am currently waiting for a plumber to inspect the distribution system installation. I have a new Intergas Xtreme boiler. Any advice or suggestions on what I could try in the meantime would be greatly appreciated.

EdTheHeaterMan

Are the grey PEX lined purged?

When you purged all the white PEX lines and you got water to flow thru each one, did you do it at the opposite end of the gray tubes? If there is still some air in the other grey PEX line (the one you didn't use to purge the white ones) then the circulator may be pulling at air in the line.

mbyregow

Thanks for responding. If by purging you mean bleeding the grey tubes, then yes, I’ve done that several times. Water flows out almost immediately from the bleed valve each time.

Alan (California Radiant) Forbes

Unfortunately, those manifolds don't allow you to purge loop by loop as there are no individual valves on the loops. And you can't use the little bleed valves at the manifold to purge air in the piping. You need a high volume of water to purge both the grey tubing and all the white tubes and it should be done with the proper valving at the boiler.

hot_rod

You might hook a garden hose and blast all the loops with high Flow/ pressure

Isolate the manifold from the boiler if you do, it cannot handle over 30 psi

mbyregow

Thank you all for the helpful suggestions—they made a huge difference. I was able to restore circulation by closing the radiators on the other floors, forcing water through the boiler input, and using the emergency exhaust valve at the boiler output. The issue was indeed air trapped in the distributor, and I could hear a lot of air being released. Now, all the radiators on that floor are heating up properly. It was quite a learning experience for me, and I really appreciate all your help!

Alan (California Radiant) Forbes

https://forum.heatinghelp.com/discussion/comment/1812569#Comment_1812569

Releasing trapped air is one of the high points in my day. So satisfying.

EdTheHeaterMan

I wonder what an emergency exhaust valve is? I'm thinking Pressure Relief Valve…. If so, that is quite an interesting way to purge air. and we know that the relief valve was operated per the manufacturer's recommendation. You know , that tag on every relief valve that says Operate relief valve at least once a year to insure passage ways are clear. That important instruction that more than half of our industry's technicians were taught to never touch because it might leak.

hot_rod

on some fire tube boiler designs, that upper relief is about the only way to quickly evacuate air. The small float vent can take days to get a big air bubble out.

Assuming there is one and its open😯