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New Main Vent Setup, New Gauges. Odd question.

Finally got all my pieces and parts together for my new main vents and gauge setup. This is all for my Weil-McClain EG-35 on a single pipe, parallel flow system.

The first picture is my new Marsh 0-32 oz/in gauge on the pigtail with the 0-30PSI. I found them mis-listed on Ebay, and got them for song.

Picture 2 is the old 'main" vents, which as you can tell are not main vents, they are convector vents from Home Depot, which I will admit that I installed when I first got the house to replace the ones that looked exactly like them, but were failed. I admit it, I knew little.

Picture 3 is the new setup. A Gorton No.1 on the bathroom loop, 45 feet out of 1 inch, with a 45 foot, return in 3/4", I mounted it up a few inches help keep it from being hammered with crap coming down the pipe. It is not at the very end of the mains, but why not try to keep my investment working. The Gorton No.2 is for the Main loop, a 50~ foot run of 2" with the rest of the radiators on it.  I mounted it up a few inches off the main, and it is on a T- with another matching pressure gauge on its own 2 loop pigtail.  i am not sure if the gauge is going to live there, but I thought it would be nice to have while I try to work the kinks out of this system. And if I need to add more vents on that main, its a port to start to antler from.

I closed up all the radiator valves and fired the system up from a warm start. From the time I could feel steam at the first elbow of the mains, to the time the Gorton No.2 closed on the big main 2 min 30 seconds. The small loop to the bathroom took just over 4 min 30 seconds.  Which is an amazing improvement from the 35 minutes it used to take I got no pressure on the gauges, until the Gorton no 2 closed and then it jumped to .75 oz/in until the other main closed and then rose rapidly. On the small loop the return piping is un-insulated, and I did get a faint water hammer from that end of the house. So I think with insulation I can get the time a little shorter on that run, and the closing times closer together.

But overall a heck of an improvement. And I should have a chance of getting the radiators on the end of the big main to warm up before the thermostat shuts the system down.

Though I did notice that the gauge on end of my mains, did always read slightly higher then the one on the boiler pigtail? Any ideas?



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  • Toymotorhead
    Toymotorhead Member Posts: 54
    Happy with upgrade.

    After doing these main vent upgrades, I am very happy. I start to get heat at the same time on all my radiators, I would not say they are perfectly balanced, but my kitchen, which is currently the last take off on the large main actually gets heat every cycle now. Which has lessened the 10 degree temperature difference down to about a 5 degree difference. (I am still working on some small construction projects in that room so there is much air sealing to be done)

    Though I did notice when I drained a little water off the bottom of the boiler last night, it had washed a whole lot of gunk out of the mains. Not the typical dirty brown water, it had a lot more solids in it. I would guess it just fast steam stripping out years of junk. I will check it in another week or two and see how it looks.

    Ever forward.


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