Look over father's plan to fix outdoor electrical circuit

Question

So to begin with, I am not a DIY'er when it comes to electricity. I prefer to allow the professionals to handle these matters as it's not something I'm confident in and not too knowledgeable about... my dad however has always been a DIY'er and I'll give him credit that throughout his years he's done many electrical projects not only at home but also for the community. Lately, his mind hasn't been as sharp due to age and the potential for maybe even dementia so of course I want to check what he's doing. At their house they had a subpanel that was ran power from the main breaker box. Inside the sub panel, there was 3 breakers, which led power to:

1. an outlet in the "pump house", a small 3x3 almost doghouse looking add on, which is used for a small heater in the winter for making sure the water line doesn't freeze up

2. a single light receptacle which is used as a back porch light

3. a single gang receptacle which sits right next to the subpanel and is only used occasionally for maybe plugging in a shop vac when vacuuming out cars.

For some reason my father stated he needed to replace the subpanel and what not. He took it off and then decided that he would use a junction box instead of subpanel for this circuit. His plan is to simply connect the 4 hot wires with a wire nut, the 4 neutral wires with a wire nut, and I'm assuming the 4 grounds with a wire nut and place them in a junction box. I'm not too sure on exactly what works and what doesn't, I even recommended that I pay someone to do it for him, but he's always been stubborn and refused it of course. So I simply ask, is what he's doing even technically the correct thing or is it something that I need to make sure doesn't happen? Is there any method that I can at least tell him to do if his idea doesn't work because I am certain he will do something to hook it all up within the next two weeks. Thanks!

Answer 1

With an appropriate breaker feeding it, this is fine.

Typical subpanel is fed by a double-pole (240V) breaker in the USA/Canada.

The feed would (per circuit descriptions) EITHER need to be a double-pole set up as a MultiWire Branch Circuit (one or two hots out on each hot in, all neutrals, all grounds conjoined) or as a single-pole if conjoining all hots. The double-pole (if used) will need handle-tie at minimum, single handle preferred.

The amperage will need to be 15 amps if there is ANY 14Ga wire on ANY of these circuits, or can be 20A if ALL wire is minimum 12Ga. That's probably going to be a smaller breaker than was feeding the sub-panel before.

The circuit will need GFCI protection given the loads served. If an MWBC, the only way to do that is with a GFCI double-pole breaker. If run as a single-pole feed, the first outlet can be the GFCI, which would then be the only thing fed directly from the breaker (on its Line terminals) and would feed everythng else (from its Load terminals.) Or that can also be a GFCI breaker, of course.

The "pump house" requires a local disconnect - that can be a 20A (or 15A if the breaker is 15A) switch.

Answer 2

As noted in Ecnerwal's answer, this is probably fine, if implemented as a proper MWBC with proper GFCI protection.

However, there may be one additional issue: hardwired loads. Normally, a circuit with hardwired loads using > 50% of capacity can't have any regular receptacles (i.e., plug-in loads) on the same circuit. In this case, the lighting is a non-issue (likely 1 Amp or less), but the heater might be an issue. The heater could be any of:

• 120V plug-in heater, presumably 1500W = 12A = max. for a 120V 15A circuit and well over 50% of a 20A circuit.
• 120V hardwired heater
• 240V hardwired heater

If it is a 120V plug-in heater, then there is no real issue. From a practical standpoint, best to put the heater part of the circuit on the opposite leg from the convenience receptacle, but no other problem.

If it is a 120V or 240V hardwired heater then you need to check the current requirements. If it is > 6 Amps on a 15A circuit (6A = 1/2 of 12A continuous) or > 8 Amps on a 20A circuit (8A = 1/2 of 16A continuous) then you have a problem. If it is a 120V circuit > 6A/8A, you must put it on the opposite leg from the convenience receptacle. If it is a 240V circuit > 6A/8A then this entire "everything on one circuit instead of subpanel" change does not work.