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lm921
Feb 14, 2009, 12:45 PM
Hi everyone, I am new to the board.
I find myself looking for a simple answer on wiring up a bunn sft-35 coffee maker.
Here is what I have.
120v house hold circuit on a 20amp breaker (nothing else on it)
Bunn stf 35 coffee maker. (google bunn stf 35) or C/P http://www.bunnomatic.com/pdfs/commercial/manuals/29251.0000. Pdf
When I opened the back of the coffee maker to hook up a cord I found a three wire ternmal, black/red/white.
After looking at the hookup instructions supplied I became confused for the 120v hookup.
Do I put a jumper from the red to the black wire to use is on 120v ?
I assume the red was for 220v but the book stated that it could be used for 120v 20 amp.
Thanks in advance.
Lee :)

stanfortyman
Feb 14, 2009, 01:24 PM
Right in the instructions:
Model 35 requires 3-wires plus ground service rated 120/240V, single phase, 60 Hz.

This is a 120/240v appliance and CANNOT under any circumstances be run at just 120v.

You need a #10 "4-wire" cord and plug and a 30A 120/240v receptacle and circuit.

Besides, it is 3900 watts. That would be 33 amps at 120v!

lm921
Feb 14, 2009, 01:58 PM
Thanks for the reply, I guess I will have to sell this one and get a smaller one :(
Thanks again.
Lee :D

stanfortyman
Feb 14, 2009, 02:48 PM
Bummer. That's a sweet machine. :(

Can't you just have a new circuit run?

lm921
Feb 14, 2009, 02:55 PM
I could do it myself but I'm too old and fat and lazy :p
There is a 20amp circuit already under the counter sink and I was going to use it but it would be easer to get a smaller machine.
I already posted it on C/L in lexington ky.
Thanks again for the help :) I really appreate it :)

lm921
Feb 15, 2009, 09:51 AM
I found another unit, stfp 15, 120v 15 amp, two wire with ground :)
It looks the same and has the water tap for hot water but is only 1800w.

I do have a question though.

The cheap and lazy side of me started kicking in, I could put in a 20amp 220V breaker and use the 12-2w/g wire that is already there and use the white wire as the other hot (marking it with black tape or sharpie).
The lengh of wire is about 30 feet from the breaker box to the gang box.

Here is what I have and what I was thinking.
I have another 20amp circuit (gang box) located right beside the 20amp gang box I was going to use for the coffee pot.
Could I use the Neutral wire from that gang box for the other circuit? (a common neutral?)
All of my neutrals and grounds are tied together in the breaker box anyway.

I have seen this setup in old buildings and from what I understand that made code.
The only problem was when the other breaker was turned off or tripped that would also kill the other circuit that shared the neutral.
Just wondering, lee :)
P.S I am buying the other coffee pot, LOL

stanfortyman
Feb 15, 2009, 10:02 AM
No, sorry, you absolutely cannot use the neutral from a different circuit. The fact that they all terminate at the same place is totally irrelevant. It's what happens once they all leave the panel that matters.

What you saw was a multi-wire circuit. This is a specific circuit where two hots share one neutral. Thing is they are all in the same cable and the neutral carries the imbalance of the current on the hots.

lm921
Feb 15, 2009, 10:18 AM
Thanks for the reply, I don't totally understand the difference in the imbalance since they all tie together in the breaker box but that's not important since I am not going to try it anyway. (I can look up that information later to get a better understanding.)
However that just brought up a new question about my breaker box.

My house is all electric, and was built in 1979.
All of my neutral/grounds are tied together.
Should they have been separate by today's standerds?
I noticed that new homes that are all electric have the grounds and neutrals separate.
What is the advantage to separate them? Does it save energy or is it just a safety feature?

stanfortyman
Feb 15, 2009, 10:26 AM
The neutrals and grounds are on the same bar in the MAIN panel. Any sub-panels down stream of the main must have the neutrals and ground separate.

If this is kind of foreign to you it's best left said that that is just how it is. This is a deep subject and can take quite a bit of typing to explain.
You can try a search if you want to read up. There have been many threads on this.

lm921
Feb 15, 2009, 10:32 AM
Thanks, I will read up.