Boiler wire up

[brad d]

Im just about finished with the wires fro my garage,, but need to run wires for radiant floor boiler. The boiler is a 12KW unit.

So i need a 70amp breaker with a 3 gauge 2 wire? or 3 wire.

14 gauge wire for 110v circulating pump

low voltage 3 wire for the thermostat??


Now would you do a plug in for the heater and pump?? or wire it up direct??

this is the heater

http://www.conceptmfginc.com/Canadian%20Brochure.pdf

[Charles (in GA)]

You don't say. Are you in Canada? NEC requires a disconnect at or close to the device, if it is more than 50 ft from, or not in direct line of sight from the circuit breaker panel. NEC 422.30 says that if the appliance is over 300 volt/amps it must have a disconnecting means if it is "hardwired", again within sight and within 50 ft.

I think you will find that a 70 amp rated receptacle and plug and cord will be very expensive (cord will have to be rated as a flexible cord). A 70 amp disconnect will be cheaper.

NEC 424.70 thru 424.86 discusses specifics of electric boilers also.

Charles

[brad d]

So hook it up to a 70 amp disconnect? Its only 4ft from the breaker panel.

And yes im in Canada, thanks for the info.

[tfi racing]

If you can get to the panel without the boiler obstructing your path,the breaker is ok as the disconnect ,if they are in the same room.
You can use #4 if you like,but #3 is easier to find,3/3 NMD can be used ,you need two hots and a ground,depending on how the boiler is mounted the wires will need to be run in conduit or flex,NMD must be protected below 5'.
T-stat wiring can be 18/2 LVT,14/2 AC90 for 120v controls and pump will do,install a service switch to shut off the 120V

[brad d]

Wired it up today, turns out the boiler has its own feed for the pump. Used 4 gauge 3 wire.. good thing it was not 3 gauge the white wire just fit in the bar.

How should this armored wire come out of the wall?

http://i44.photobucket.com/albums/f43/leyanh/Shop6/power003.jpg

http://i44.photobucket.com/albums/f43/leyanh/Shop6/power002.jpg

[79firebird]

For the armored cable you are missing the little sleave that goes inside the end. It stops the metal from cutting the cables. Last time i forgot to put one of thoes in at my work the inspector failed us.

[tfi racing]

Yes,you need the little red plastic anti-short as its called.Also that connector is the wrong type,you need one for AC90,not NMD.You may get away with it if you insert the anti-short and make sure the flex is not showing past the connector.

[brad d]

OH yeah thats right not the right connector.. Thanks for the tips guys