New deep well wiring question

[Bill Rogers]

Have a 1hp 10gpm well pump 200' down, and will be pulling power from 220 feet away. All the charts I have looked at say 10 gauge will easily handle that load and distance.

The pressure tank, filters and and piping will be in an insulated 6x6 pump house so will need a heat source for winter time. Not sure yet if it will be a heat lamp, heat tape, or what so want a little built in cushion on wire size.

Without knowing the exact heating requirements do you think 8 gauge would be sufficient or should I drop down to 6 gauge?

Once again it will be in a small insulated shed, and our winters rarely get below 20 degrees.

 

[2stupid2fixit]

Have a 1hp 10gpm well pump 200' down, and will be pulling power from 220 feet away. All the charts I have looked at say 10 gauge will easily handle that load and distance.

The pressure tank, filters and and piping will be in an insulated 6x6 pump house so will need a heat source for winter time. Not sure yet if it will be a heat lamp, heat tape, or what so want a little built in cushion on wire size.

Without knowing the exact heating requirements do you think 8 gauge would be sufficient or should I drop down to 6 gauge?

Once again it will be in a small insulated shed, and our winters rarely get below 20 degrees.

I think you are saying a lot when you mention that you don't know what heating source will go in there. 6 gauge wire is suitable for a 55 amp sub panel, your pump will probably dead start draw around 18 amps (I AM ONLY GUESSING) and that leaves leftover around 35 continuous amps for your heating apparatus. We have really not solved anything, though. In my opinion, the only way you can get a clear picture of what materials are appropriate is after you know what equipment you will be using. Reasonably priced "smart" heat tape could cover every water part of your install while drawing less than an amp in -5 fahrenheit situations. I don't think you will be ahead of the game if you choose to work within the confines of wiring that is going in now, just because you want to or can do it n0w. Hell why not just provision your pump house to have a 200 amp sub panel? Its prob wasted resources but I'm confident y0u will have plenty. Or... you could do some serious homework on self regulating heat tape, you might save thousands if you engineer your solution that way.

 

[Sponsor]

 

[Valveman]

No matter what size wire you end up running to the well house, you should run 250' of #14 wire down the well to the pump. Using the longest length of the smallest wire possible for the 1HP pump will give you a reduced voltage soft start. No fancy soft starters needed if you don't oversize the wire to the pump. The small wire will reduce the start torque by 36% all by itself. Then using a Cycle Stop Valve to limit the number of on/off cycles will greatly increase the life of the pump.

 

[Bill Rogers]

No matter what size wire you end up running to the well house, you should run 250' of #14 wire down the well to the pump. Using the longest length of the smallest wire possible for the 1HP pump will give you a reduced voltage soft start. No fancy soft starters needed if you don't oversize the wire to the pump. The small wire will reduce the start torque by 36% all by itself. Then using a Cycle Stop Valve to limit the number of on/off cycles will greatly increase the life of the pump.

Wire to the pump was run by the well company who dug the well and installed the pump. They ran as far as the pressure switch, I will be running the rest.

 

[Bill Rogers]

I think you are saying a lot when you mention that you don't know what heating source will go in there. 6 gauge wire is suitable for a 55 amp sub panel, your pump will probably dead start draw around 18 amps (I AM ONLY GUESSING) and that leaves leftover around 35 continuous amps for your heating apparatus. We have really not solved anything, though. In my opinion, the only way you can get a clear picture of what materials are appropriate is after you know what equipment you will be using. Reasonably priced "smart" heat tape could cover every water part of your install while drawing less than an amp in -5 fahrenheit situations. I don't think you will be ahead of the game if you choose to work within the confines of wiring that is going in now, just because you want to or can do it n0w. Hell why not just provision your pump house to have a 200 amp sub panel? Its prob wasted resources but I'm confident y0u will have plenty. Or... you could do some serious homework on self regulating heat tape, you might save thousands if you engineer your solution that way.

Yeah I know I can't really decide what wire size I need without knowing the heating load. My thoughts were worst case I have a 1500 watt space heater running (actually plan on heat tape) then it seems the 8 gauge running to a 30 amp sub panel should be enough. Just looking for educated guesses really, as they are trenching now and will be running wire on Monday. We were originally running 10 gauge wire with no thoughts on heating, so kind of last minute scramble. Why I joined here, seems like a lot of experienced people in this group.

 

[Valveman]

Yeah I know I can't really decide what wire size I need without knowing the heating load. My thoughts were worst case I have a 1500 watt space heater running (actually plan on heat tape) then it seems the 8 gauge running to a 30 amp sub panel should be enough. Just looking for educated guesses really, as they are trenching now and will be running wire on Monday. We were originally running 10 gauge wire with no thoughts on heating, so kind of last minute scramble. Why I joined here, seems like a lot of experienced people in this group.

I think with most things you can't get too large of wire. Just not so with submersible pumps.

 

[Reach4]

Are you thinking of putting a subpanel into the well house? You should.

Do you intend to have 120 volt heater in the well house? It is possible to only have 240 volt outlets in the well house, and save a buried wire, but you would find the convenience of having 120 volts available to be handy. Also consider putting an outdoor outlet on the well house, protected by GFCI, of course. Nice for yard stuff. Maybe even put in an outlet for that new welder.

Add some XPS or EPS insulation into the well house, and you won't need 1500 watt heater. Something much smaller would be enough.

 

[Bill Rogers]

Add some XPS or EPS insulation into the well house, and you won't need 1500 watt heater. Something much smaller would be enough.

I understand that's overkill, was a worst case scenario when figuring wire size

 

[Reach4]

I understand that's overkill, was a worst case scenario when figuring wire size

If you intend to have 120 volt outlets, you can feed heaters through outlets on opposite legs.

Even a 4o amp subpanel could easily power your pump and a couple of 1500 watt heaters, and some lights.

I would avoid heat lamps, since they are more likely to fail than a milkhouse heater.

 

[Bill Rogers]

Thanks for everyones input. Went ahead and bought the 6 gauge, only $100 difference and that was worth it for peace of mind.

 

[Boycedrilling]

I normally install a 60 amp service to a sub panel in a domestic well pump house. Unless the pump is 3 hp or larger. You have to pull 4 wires to a sub panel. Two current carrying conductors, a neutral, and a ground conductor. To be NEC code compliant, you need the branch circuit for the pump, another for heat, another for at least one 120 volt outlet, and a circuit for interior and exterior lights. If you have more than 6 circuits, then you have to have a main disconnect in the sub panel.