Garage electrical - minimum distance between water source and junction box

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Posted by: from Edmonton
12/3/2015 at 10:33:04 AM

I am installing a 240V heater in my garage and have the Alberta simplified Electrical code book as a reference.

The problem is I can find no reference to the minimum distance between an existing hose bib, and the planned junction box.

My plan is to drill a new hole roughly 1 foot from a hose bib with a junction box, running armored cable up the wall to a ceiling mounted heater. I am unclear if I can use a standard metal junction box in this case due to the close proximity to an active water source. The armor cable will terminate in the junction, with standard NMD90 12/2 inside the house to the breaker box.

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Date/Time12/3/2015 at 11:46:57 AM

Hello and good morning. Believe it or not there is no minimum distance from a hose bib and an electrical junction box as long as there is not a wash basin attached. If this is the case then the junction box would have to be at least 1m away. You may use a standard surface mount metal box such as a 4x4 or 1110.

Also the electric heater will need a 2-pole disconnect switch if it is to be hard wired and not a plug in type.

Good luck with your electrical project!

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Robert from ElecTriLight Ltd. in Oakville
Date/Time12/3/2015 at 4:02:43 PM

Armoured cable cannot be run on the surface below 7', it is not considered to be protected against damage. The easiest way to cover code is to buy a piece of rigid pvc pipe and run it up the wall with the NMD inside of it. The outer sheath of AC-90 (armoured) is aluminum and is meant for steel stud use or other metal framed areas. NMD needs to be protected below 7' AFF.

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Date/Time12/3/2015 at 5:37:47 PM

That close to water would be safer to use PVC box and PVC on surface but you can use standard box and bx if you wish. Bx is already protected because of it's armor sheath. In Ontario all surface mounted cable needs protection 1.5 meters AFF.

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Date/Time12/3/2015 at 5:50:43 PM

You may need to look at GFCI protection on the circuit if you would like added safety for electrical near water.

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Robert from ElecTriLight Ltd. in Oakville
Date/Time12/3/2015 at 8:12:10 PM

Canadian code rule states: Where mineral-insulated cable, aluminum-sheathed cable, or copper-sheathed cable is installed on the face

of a wall, partition, ceiling, or structural member within 1.5 m of the floor, and in all locations where subject

to mechanical damage, as for instance from industrial tractors, other vehicles, equipment, stockpiling, or

excessive vibration, a suitable safeguard against such damage shall be provided. IE-rigid pvc conduit

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Date/Time12/3/2015 at 9:53:23 PM

Just to add to some of the confusing answers already posted...

Sounds like you know the wattage of the heater thus the 12/2;

Someone pointed out that you need a disconnect or the unit must be plugged;

Cable (NMD90 or AC90) cannot be run below 1.5 meters without mechanical protection;

GFCI protection is not required by code unless the receptacle is below 1.7 metres;

Cable (NMD90 or AC90) cannot be run inside a conduit system what does that mean?

You can use a section of conduit (or any type of pipe or fittings to mechanically protect the wire, but you cannot complete the system by having it end at a box / receptacle that is attached to the conduit / pipe.

However no one has mentioned that you cannot penetrate through the wall of the garage to the living space without using a properly sealed method. As soon as you drill the hole in the wall you have comprised the living space with potential carbon monoxide.

My recommendation would be to:

Use NMD90 wire;

Stub a short piece of PVC conduit through the wall with an LB fitting;

Run a short section of pvc conduit up the wall to 1.7 metres;

Exit the conduit with the wire to the receptacle box; and

Use a proper receptacle and approved connector for the NMD90 wire.

Be sure to seal the inside of the LB fitting with duct seal and drywall compound around the conduit to fill any gaps. Repair any issues with the vapour barrier.


John Kuehnl-Cadwell

Master Electrician

Datawise Solutions Inc

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