Due to the incomplete label, I offer a word of caution.
If the power rating is associated with the current wiring, and you do as suggested, you could be in for a big surprise. I recommend measuring the resistance of the elements before making any commitments. I would also be looking for the appropriate certifications

 

I would imagine after 4 years, if there was a problem, the OP would have come back?
What is the problem with the current recommendations??

 

How do you mean, "how will it react"?
It should trip on a GND fault.

I am curious if wiring it as In the diagram above will cause the GFCI to trip. If it trips on a fault it will not be a problem.

Looking at the diagram again, Could I just not connect anything to L-3? in other words connect 1 phase (red wire) to L1 on the contactor, connect the other phase (black wire) to L-2 on the contractor. Leave L-3 unoccupied. Connect neutral(white wire) to the common point of the Star, and bare ground wire to gnd.

It appears to me that I would lose 1/3 of the heating capacity, but for my application, that's no problem.

 

Missed the dates.

If the data plate is indicating the wattage and voltage wired wye, then paralleling the elements would produce a substantially different wattage.

 

Missed the dates.

If the data plate is indicating the wattage and voltage wired wye, then paralleling the elements would produce a substantially different wattage.

I checked the heater elements and they are definitely wired in a star configuration.

 

So do you want to feed them from 1ph as did the OP?
It will be the same heating effect connecting to 1ph as it was in the 3ph configuration.
The label shows single or three phase.
On the three phase and neutral, you effectively have three single phase heaters in parallel

 

If you calculate the element resistance with given total wattage and volts, in a wye configuration, then parallel those elements with the given voltage...

 

Essentially what I said.
In the star connected 3 ph, you essentially have three 1ph loads for each of the elements. Each phase to neutral.
The only thing I would correct is that each of the 1ph conductors should be switched by the contactor, L1 & L2.

 

Howdy, I need to clarify what I mean:

To the best of my knowledge (which isn't saying much) the GFCI measures the difference between current flowing between live or hot wires and the neutral wire. When there is a difference the GFCI trips breaking the circuit. So as far as "how will the GFCI react", the GFCI will operate properly regardless if I wire the heater 3 phase or single phase, it will only trip in the above scenario if there is a difference between current flowing through any leg and the neutral leg. So at least I'm clear on that part (I hope).

There has been a reference to current flow if I wire it as a single-phase where one of the live wires is connected to all three terminals on the contactor. In that configuration, the 3 heater elements are in parallel, and as such, the total resistance in the circuit is about one-third of the resistance in each single heater element. As a result of the lower resistance, the current flow in the wire will increase requiring a larger wire to avoid overheating the wires carrying the current to the heater.

The heater elements are wired in a star pattern meaning that when wired as 3-phase each of the live wires is connected to their respective heater element and the other end of the heater elements are connected to the neutral wire. In this configuration, the voltage drop across each element is approximately 120 vac.

Measured between the terminals of the contactor the voltage will be 220 vac. So one question is, will there be current flow between the legs of the circuit? In other words, will there be current flow through the heater element on one leg and the heater element of both the other legs as a result of the voltage difference between one leg and another?

Also, If I wire the contactor as if I had three-phase power, but only connect two of the legs to their respective terminals (two-phase?) the heating element of the third leg will not be passing current at all, in effect electrically, not be a part of the circuit. Resulting in a resistance that is two-thirds of the total resistance if the heater was wired properly as a three-phase. In that case, a larger feed wire will still be needed but not as large as if wired as single phase. And if I'm not mistaken, the heater should operate properly and safely, but instead of being an 11kw heater, it should only be a little over a 7kw heater, which will be quite adequate for my application.

How close am I to reality??
Thanks

 

Essentially what I said.
In the star connected 3 ph, you essentially have three 1ph loads for each of the elements. Each phase to neutral.
The only thing I would correct is that each of the 1ph conductors should be switched by the contactor, L1 & L2.

I didn't see this until after I posted my long post. But if I read it correctly, I should be okay to wire it like you are saying, L1 & L2 wired at the contactor and neutral wired to the center of the star?

 

No neutral if you are wiring it to 1phase 240v. (it is not 2 phase)
The star neutral only applies to the 3ph installation. so no neutral needed.
The GFI detects an unbalance between two conductors, what ever they are.
The contactor should switch both conductors and be rated with the required current rating.
On 1ph, the resistance of the load is the total of all three elements.
In the 3ph installation, each phase is 220v to the star neutral point, the supply connection of each element in this case is 220v across each element. IOW, effectively 3 x 1ph loads.

 

I’m going to bow out, as my response was to the OP of this thread, in an untimely manner.
But, for anyone that chances across the thread and wonders what that was about,
The equipment label indicated 5.5k watts at 220vac and shipped wired in a 3 phase, Y configuration. Calculations would put the individual elements at ~8.8 ohms. The suggestions were, as I believe to have read, was to parallel those elements on a 2 pole breaker, on a #10 wire. I cautioned to review that approach. It would ultimately be up to the Electrician doing the installation, and in that case, in my view, the label indicates a non compliant device.

 

No neutral if you are wiring it to 1phase 240v. (it is not 2 phase)
The star neutral only applies to the 3ph installation. so no neutral needed.
The GFI detects an unbalance between two conductors, what ever they are.
The contactor should switch both conductors and be rated with the required current rating.
On 1ph, the resistance of the load is the total of all three elements.
In the 3ph installation, each phase is 220v to the star neutral point, the supply connection of each element in this case is 220v across each element. IOW, effectively 3 x 1ph loads.

Heres where we differ.
A Y connection reduces the phase voltage. You are basically suggesting going from a Y to a delta, and dropping a phase. That will have a substantial impact on current, and total wattage.
Think delta/Y soft start. The Y is soft, because of the reduced voltage.

 

Who mentioned Delta?
I was referring to the original star connected element to each phase WRT neutral,
The issue is the conversion to 1ph 240v, at least that was the original OP's intention.
All that is happening in this case is that all three elements are fed from the L1 L2 1ph line.
The heater label, denotes 1ph or 3ph.
The proper sizing of 1ph conductors and contactor is all that is needed.
Assumably the OP's installation worked OK as installed by his electrician.

 

Howdy, Here is what I have:

So what I am proposing is connecting the black wire to L1 of the heater, the red wire to L2 of the heater, and the white to the center of the star. I'm not sure what the center of the star is called, Common, Neutral or what.

 

What are you feeding the neutral with?
It is not needed for 1ph 240v.
The elements connected will only operate on 120v that way!

 

"What are you feeding the neutral with?"

Sorry for my ignorance, but I don't understand what you mean by "feeding the neutral"

"The elements connected will only operate on 120v that way!"

That is acceptable to me as long as it's safe and I get at least 5Kw of heat.

 

Who mentioned Delta?
I was referring to the original star connected element to each phase WRT neutral,
The issue is the conversion to 1ph 240v, at least that was the original OP's intention.
All that is happening in this case is that all three elements are fed from the L1 L2 1ph line.
The heater label, denotes 1ph or 3ph.
The proper sizing of 1ph conductors and contactor is all that is needed.
Assumably the OP's installation worked OK as installed by his electrician.

I mentioned delta as a perspective.
The label indicates 5.5k watts at 220 vac, and delivered 3 phase Y. That calculates to a 8.8 ohm element. Paralleled results in an approx 3 ohm element. At 240vac you’ll draw 80 amps and deliver 19k Watts.
Is that what is wanted? I suppose it could be, but we can see that the label fails miserably. To that, I raise a caution.

 

Howdy, Just for informational purposes the wires feeding the circuit breaker is 10/3, and each of the heater elements read 15.6 ohms. I don't know if that helps anything

 

Howdy, Just for informational purposes the wires feeding the circuit breaker is 10/3, and each of the heater elements read 15.6 ohms. I don't know if that helps anything

Interested to see what your label says, for interest sake. Knowing the element resistance allows you to make some decisions.