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Restorations => General => Topic started by: vendo81d on August 26, 2014, 02:26:27 pm



Title: S-47 wiring
Post by: vendo81d on August 26, 2014, 02:26:27 pm
I am trying to fix some problems on one of my earlier restorations.  It is a 7up S-47 machine.  I need to know exactly how this machine is wired.  It is a little unusual in that it has a switch on the door and a valve on the Blissfield refrigeration system that when activated recirculates warm freon to defrost the evaporator. If you have one of these machines and can send me some pictures of the wiring I might be able to figure out the rest.  I specifically need to know which wires go to the switch in the front and which wires go to the valve.  I might also help to see a picture of the junction strip at the rear of the machine on the right side.


Title: Re: S-47 wiring
Post by: johnieG on August 26, 2014, 09:05:51 pm
Wow...hot gas defrost on a soda machine, pretty fancy for a medium temperature application, you'd expect it on a freezer / low temp unit, not a soda cooler...


Title: Re: S-47 wiring
Post by: vendo81d on August 30, 2014, 02:10:41 pm
What's confusing me on this machine is the switch.  It has four contacts.  What seems logical to me is that two contacts would have continuity when the button was released and the other two would have continuity when the button was pushed.  That way I would connect the evaporator fan to the contacts that work when the button is pushed and I would connect the hot gas valve to the contacts that work when the button is released.  However, when I checked the contacts, I found that there is only continuity when the button is pushed (one pair on each side of the switch).  I know that the machine won't cool if the valve is released.  I could just skip wiring the valve since it isn't really necessary, but I was trying to make everything work as originally intended.  I guess I could also try getting a different switch.


Title: Re: S-47 wiring
Post by: johnieG on August 31, 2014, 08:14:22 am
What's confusing me on this machine is the switch.  It has four contacts.  What seems logical to me is that two contacts would have continuity when the button was released and the other two would have continuity when the button was pushed.  That way I would connect the evaporator fan to the contacts that work when the button is pushed and I would connect the hot gas valve to the contacts that work when the button is released.  However, when I checked the contacts, I found that there is only continuity when the button is pushed (one pair on each side of the switch).  I know that the machine won't cool if the valve is released.  I could just skip wiring the valve since it isn't really necessary, but I was trying to make everything work as originally intended.  I guess I could also try getting a different switch.

that sounds almost like you're describing an old manual push-to-start florescent lamp switch.... :oh:  one set of wires is a momentary/normally open ( push to "strike" the lamps filaments) & when you release it, it would "make" the second switch to keep the current flowing to the lamp via the ballast...

But yeah, you don't really need it unless you're in a high humidity environment, these machines were designed to "air-defrost" between cooling cycles ( which is one reason why the Evaporator fans running constantly even in modern coolers.)


Title: Re: S-47 wiring
Post by: vendo81d on August 31, 2014, 06:03:56 pm
I think you may be onto something.  The switch does "click" when you push it.


Title: Re: S-47 wiring
Post by: johnieG on August 31, 2014, 08:46:23 pm
it would have a total of four wires, two of one color ( typically blue) & two of another ( typically black) to identify the corresponding switch functions...