I am having a waterfall(small) installed in back of house. What I was looking to do is as follows. Already have a GFI outlet on back of house. I want to run a FLEX conduit underground and put a outlet on both ends. Then make a short 3ft cord to connect existing outlet on house with new one. Basically creating a long underground extension cord. Questions are, do I need to make sure the 3ft cord white/black wires are in certain positions or does it matter? Also, since I am running the FLEX conduit underground can I use regular indoor wire to run through it? What would the recommended Guage I use..14/2 or 12/2. And finally, do I need to make either end of the new run a GFI since the one on the side of the house already is?
Ah heck one more question. Since the underground wire will only have power when I connect the jumper, should it be ok to just burry the flex conduit 5-6 inches down.

Thanks

 

Most flex conduit is not approved for underground use. Make sure that whatever you use is.

You may not make an extension cord with a male plug on each end.

It always makes a difference what the positions of the black and white wires are in a 120-volt circuit.

You may never run indoor wire underground.

Gauge of wire depends on the amperage draw of the pump, the distance to it, and the size of the breaker.

If there is already a GFCI, there is no reason to put in a second one.

You need at least a 12" burial depth.

You appear to be trying to invent a creative solution. I strongly suggest you simply use a more conventional solution. It will not be any harder nor more costly to do it right. Many books on home wiring will show you how to add an outside receptacle properly.

 

John,

The flex conduit says on it outdoor direct burial. So I am assuming that it is ok to do so.

From what I read on the packages of electrical wiring, the outdoor wire was for running the wire by itself (no conduit) that is why I was wondering id it was ok to run indoor wiring through the conduit, because the conduit is actually protecting the wire.

If I make a direct run to my panel in the garage it would be approximately 100ft. I would assume that 14/2 would probably be out of the question?

Just trying to do what would be the simplest, yet still ok to do so.

 

The wires have to be rated for wet locations. There should be a marking on the wire's insulation with the letter W in it. W means rated for wet locations.

As for the flex, is it metallic with an outer jacket? Liquid Tight Flexible Metal Conduit can be buried if its manufacturer says so. You stated that it said on the flex that it's rated for direct burial. So bury it.

Is there a chance of any vehicle traffic where the LTFMC will be buried? The burial depth of the LTFMC is determined by some factors one of which is vehicle traffic.

I would venture to guess that burial depth will be 12"-18" deep from the top of the LTFMC to grade. This is barring any vehicle traffic over the LTFMC.

The burial depth table in the 2002 NEC doesn't list LTFMC, so I would connect it with the burial depth for PVC conduit. That's just my preference though.

 

kuma, to get the best advice from us, you need to provide more specific information. Exactly what kind of conduit is this? Exactly what kind of wire? What are the specs of the pump? Tell us what is says on the package of conduit, on the package of wire, on the nameplate of the pump.

It is never okay to run indoor wiring underground. Never.

 

Is the box that holds the gfci recept flush mounted or surface mounted. If it is surface you can pipe right out the bottom of it.

 

Well, I guess a trip back to home depot to get the outdoor wire is needed. I'm going to run a feed from the main panel in the garage into the basement to where I am going to drill a hole through the side of the house and connect in a splice box.
I'm not sure of the specs of the pump, the contractor is no where close to finishing that part yet. Still laying concrete pavers for patio & walkway. All I can say is that the pump is suppose to pump up to 3000 gallons an hour (I beleive).
If the total length of the run is approximately 100ft would I be better off running 12/2 or 14/2? I will have the pump running on that circuit and probably some low voltage accent lighting. Also, what size breaker should I install, 15amp or 20amp? This will be a dedicated circuit.

 

Most waterfall/pond pumps that size are only about 2 to five amps. So if you have another filter, pump for a skimmer, etc., the amperage is still not very high. I'd suggest a four plug GFCI fixture for possible expansion. the 15 amp sh be okay, but I'd bump it up to the 20 amp.
fred

 

I recommend 12-gauge THHN/THWN on a 15-amp breaker.