Old House = No Grounding

[bizzle]

I'm in the process of setting up the electric brewery using my dryer plug, splitting the 240v into two 120s then powering two heating elements which plug into two separate GFCI Plugs that I have installed in the panel. My question is: my old dryer plug has no ground. What would be a cheap easy way to achieve this or am I adequately protected by the two GFCI plugs I have on my panel.

Thanks in advance for helping me not accidentally kill myself!

 

[dyqik]

I'd suggest using 240V elements with a power controller and switches, unless you are doing a small (2.5 gal or smaller) batch size system.

You can use a spa panel with GFCI breaker to provide 240V protection and a four wire output allowing two 120V circuits to be used after that point - there are many diagrams around here, although a lot of the links to images seem to be dead.
This one seems to still work: https://www.homebrewtalk.com/showthread.php?t=266751&page=5

The second post on this thread gives a pretty fair overview of the pros and cons, I think, and you should read it first before going this route.
https://www.homebrewtalk.com/showthread.php?t=372667

The "best" long-term cost-no-barrier option is to get a four wire run to the dryer socket installed. Then you can either go to a GFCI breaker in the main panel or in a spa panel. It may be worth checking that you don't already have 4 wires to the outlet, with the ground disconnected inside the outlet box (hey, there's a chance...). Then four wire is just a change of outlet.

Personally I run my kettle off a simple 240V power controller box with a GFCI breaker in the main panel, and run my pumps and RIMS tube off a separate 120V GFCI circuit, even with four wires to the dryer outlet. This is because I use the pump and RIMS controller in a separate water bath system for cheesemaking (could also be used for sous-vide I guess), and because the GFCI breaker for my particular panel (BR type) was as cheap as a spa panel.

 

[bizzle]

I had the box assembled some time ago and I don't remember what I was thinking at that time. Possible wanted to power at pump and and element out of the same box but my thinking has changed and while there may be a better/different way out there I am pretty set on this method.

That said with both elements being connected to a GFCI my thought is that I am protected (obviously could be better with a ground). Is that true? Thanks for your thoughtful reply.

 

[doug293cz]

You are not completely protected with your GFCI arrangement. Your element wiring, elements, and kettles (anything downstream of the GFCI's) are protected, but your control panel itself is not protected, because everything inside the panel is upstream of the GFCI's. Since the panel will be in a wet area, it needs to be GFCI protected as well.

Also, how are you grounding your elements and control panel enclosure?

Brew on

 

[bizzle]

Unfortunately unless I come up with another solution the box itself would not be grounded. I built the box with ground wires and a bus that when plugged into a grounded dryer outlet would ground everything.

 

[doug293cz]

Unfortunately unless I come up with another solution the box itself would not be grounded. I built the box with ground wires and a bus that when plugged into a grounded dryer outlet would ground everything.

Your elements and kettles also appear to be ungrounded, if I understand your wiring correctly.

Brew on

 

[beermanpete]

The older houses I have worked on have the neutral connected to earth at the panel. The boxes and metal conduit are usually connected to ground/earth. Does your dryer plug have three wires? If so, one should be neutral and/or earth.

You can add an earth ground near your brewing system if there is no other reliable ground available. A cold water pipe is a common ground point in many homes. If that is not an option drive an 8 foot copper rod into the ground and connect the ground wire to it.

 

[z-bob]

I'm in the process of setting up the electric brewery using my dryer plug, splitting the 240v into two 120s then powering two heating elements which plug into two separate GFCI Plugs that I have installed in the panel. My question is: my old dryer plug has no ground. What would be a cheap easy way to achieve this or am I adequately protected by the two GFCI plugs I have on my panel.

Thanks in advance for helping me not accidentally kill myself!

If the dryer plug is installed properly, the neutral wire goes all the way to the main breaker panel (not a subpanel), and in the main panel the neutral is bonded to ground; that's the only place it's supposed to be bonded. What that means is you can safely use the third wire as a ground or a neutral (but with only a few very specific exceptions, not both at the same time.)

So if you can set up your system so everything is 240V and no 120V loads, you can pretend the dryer outlet is pure 240V, like a NEMA 6-30. I don't know if you get a GFCI to work like that...

You could also run a separate ground wire to the outlet box and install a 4-wire receptacle (I think it's called a NEMA 14-30). The grounding wire does not have to be run with the current-carrying wires when you are updating old work. If you have an electric dryer, you'll also have to get a 4-conductor cord for it.