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Republic Gyroscopic Boiler

dbruening Member Posts: 2
I am posting this message as I found, based on a old post, that you may have a manual for my Republic Gyroscopic Balance boiler made by Autogas (sometime in the 50's presumably). This forum has been a wealth of information regarding old boilers and I am thankful to learn. I've never had a boiler before and this is all new.

Know that while I have installed many gas forced air furnaces, I have no intention to service or repair, this boiler-i just want to understand it! And as its my daughters (new to her) house I want to make sure its safe. the model is "SW-4'" and the serial is "4127" btu 160,000. Based on reading your various excellent answers I have determined that its a gravity system.

I basically have two questions:

1. The main gas valve has a dual pilot tube connection. I understand that one of these is or may be a "bleed" valve but I still haven't grasped what it actually does. I will say that when the pilot light is lit, when this valve is closed it doesn't affect the pilot light.
2. The pilot light and valve. This is the most perplexing part. I turned off the main gas to hook up a stove and when turned back on, I was surprised to note that their was gas coming from this furnace. It appears that there is no thermocouple to keep the gas from flowing should the pilot light go out. Also there is no pilot position on the valve (honeywell VR83404M 1141). How could this be? of course my concern is should the pilot light get blown out there is nothing stopping it from seeping gas. I also wonder if the pilot light is out and gas is called for, without a thermocouple would the gas come on? Perhaps there is a different type of safety mechanism on it which would allay my fears, and I'm hoping you could shed some light for me.
Thank you in advance, your collective expertise is much appreciated.

oh, and 3- I'd love to have a manual should you have one to download!



  • Larry Weingarten
    Larry Weingarten Member Posts: 2,291
    Hello, Your system predates the 100% safety shutoff gas valve in use today. There are modern gas valves made that you can replace the existing setup with though it will take redoing the piping and tubing a bit.
    No doubt others here will want you to see if the boiler is even worth working on. First things first!

    Yours, Larry
  • mattmia2
    mattmia2 Member Posts: 3,991
    I'm sure someone here can identify it immediately, but there is some sort of pilot safety on there, maybe a thermopile based system. The pilot is always on, but the main valve won't open unless it proves pilot. Is there a transformer somewhere or is it run off the current from a thermopile(so if the pilot isn't heating the thermopile there is no current to open the main valve)?
  • dbruening
    dbruening Member Posts: 2
    Thanks guys, I'll trace it to see if there is transformer; I thought that a thermopile system has a device that (resembles a thermocouple, but larger) energizes the valve through the pilot and maybe it there but out of sight. Mattmia2-thats reassuring about the main valve...The furnace has been working fine, its really the safety and if I need to have it improved upon. Larry- I like the idea of having a modern valve and having the piping reworked..
  • mattmia2
    mattmia2 Member Posts: 3,991
    edited September 2020
    You could try bumping it to the top tomorrow morning when more of the trade people will see it too.

    The coil voltage of the valve will tell you if it is a 24vac system with a transformer or a milivolt system with a thermopile. Whatever that device with the window I think is part of it, just not up on 1950's gas components.
  • Mike_Sheppard
    Mike_Sheppard Member Posts: 680
    edited September 2020
    Looks like a VR8204M1141 gas valve. Which is a 24v gas valve. So there has to be a transformer somewhere. And possibly a baso switch or something with a thermocouple attached to it to sense the pilot flame, or some sort of similar device that passes voltage to the aquastat when flame is sensed. Can’t see anything in the pictures.
    Never stop learning.
  • mattmia2
    mattmia2 Member Posts: 3,991
    Maybe this is a @Tim McElwain level question.
  • Tim McElwain
    Tim McElwain Member Posts: 4,481
    A lot of older systems had what is called a "Wild Pilot" that if it went off it relied on the natural gas escaping would go up the gas vent as natural gas is lighter than air.

    It looks like this Republic Gyroscopic has been upgraded at some point with a more modern what appears to be a Honeywell valve.

    You are not getting pilot gas from the valve as the pilot tubing connection on the valve is plugged off so I am sure you have a wild pilot getting its gas from the combination "B" valve (pilot) and "A" valve main gas.

    I have a manual for Republic Gyroscopic which I can have printed up and mail to you. Contact me at [email protected] and I will give you the particulars on receiving the manual.