Inspecting the wiring to electric water heaters
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- เผยแพร่เมื่อ 9 ก.ย. 2024
- As a home inspector, I look for three main things when I inspect the wiring to an electric water heater: protection of the wires, a service disconnect, and proper circuit size. Today I'll explain all three.
Thank you Mr inspector 🤠👍
So, just to clarify... The conduit only has to cover the vertical drop of the wire from the water heater to the ceiling, or does it need to travel a certain distance covering the wire? Also, I was told it is not ok to have romex type wire in conduit due to possible heat? Lastly, sorry, can other types of conduit be used - say, some CPVC or PVC pipe large enough, or does it need to be metal or typical conduit bought specifically for conduit covering?
Thank you for sharing. Speaking of means of disconnect, whether that be the breaker box within sight or a separate switch, it is required to be double pole, I was once shocked while changing an element because it was an older panel and if I remember correctly there was two single pole 30 amp breakers instead of a two pole, and after testing across the upper thermostat with my wiggy , the circuit was dead, or rather appeared to be dead, but one leg was still hot, never thought to test each terminal to ground as I was 17 at the time. Something to keep in mind.
Home Depot &/or Lowes sell Siemens, Square-D, Eaton & GE brands of dual-pole 25 Amp breakers for ~$13 to $17. Not necessarily "in store" available, but can be ordered on-line & shipped to store for pickup.
I have seen many older homes feeding water heater from 20A 2 pole breaker and #12 wire. Home owners have never had the breaker trip. That is with 4500W elements. As a side note, #12 wire is rated for 25A, but limited to 20A on receptacle circuit.
A 4500 watt element @ 240 volt draws 18.75A. If you live in a large apartment building or condo you might have 208 volts in which case that element will draw 16.25A and produce 3,380 watts. But the NEC considers a water heater to be a continuous load, and the wire and breaker/fuse must be sized 125% of the nameplate rating, which means 10 gauge and minimum 25 amp breaker.
Question. I’m renting a townhouse that has bare wire to the HW tank from a hole in the wall. No conduit. It’s in the open with things around, where we move things and also cats in garage. Owner not willing to do it correctly. Cats beginning to chew on wire. For temp solution, I bought some corrugated plastic wire organizer that’s split in half to push wires into. I put it around the wire to keep the cats from biting it
Is this safe? If not, outside of the owner reinstalling correctly, is there any material I can cover it while connected?
Bx cable does not need to be protected, the metal casing is the protection
For your typical 4500 water heater, it could be on a 25 amp breaker and meet code, but that size is not as common as the 30, and since you must use 10AWG conductors it's a standard practice to install 30 amp overcurrent protection. Some water heaters have 5500 watt elements and requires 30 amp protection.
In some older installations, like I found in my step fathers 1973 rambler, the 40 gallon electric water heater was plugged into a 30 amp 240 volt receptacle like you might find on a kiln or arc welder, the breaker panel was located in a bedroom closet, water heater in the laundry/utility area. Today this would never be permitted, but perhaps a cord and plug connection was a means of disconnect for a water heater many years ago?? Anyone ever ran across something like this? Feel free to comment.
Can I run a direct wire from my service panel to my water heater, It would be about a 40 ft run through my attic and down from the ceiling to the water heater
Yes. You need 10-2 NM, a two pole 25 or 30 amp breaker, and a disconnect switch must be installed near the water heater since the service panel is not within sight. The white conductor must be re-identified as a hot conductor at all termination points with black or red tape, paint or heat shrink. As shown in the video a lockout at the breaker box is an acceptable substitute for the disconnect switch per the NEC, but some local codes could require a disconnect switch anyway. A 30 amp double pole toggle switch is also acceptable. Cord and plug connection is NOT acceptable, although you may run across a 3 wire dryer or range cord, or a length of NM with a 3 wire dryer/range/NEMA 6-30P on the end plugged into a receptacle to serve the disconnect means in older homes. The NM from the disconnecting means to the water heater must be ran in flexible conduit.
I was hoping I didn't have to get more parts I got about 45 ft of 10-3 and I was hoping just to run it through some 1/2-in steel flexible conduit and put a box in the ceiling right above the water heater
@@johnh9507 you can also use 10-3 if you already have some laying around the house, you'd simply cap off the neutral with a wirenut since a water heater is a straight 240V load and doesn't use a neutral. You still need a means of disconnect to be code compliant, a lockout at the breaker is probably the cheapest way to meet code if the local inspector allows it. If not a 30 amp double pole toggle switch is the next cheapest option and they are readily available at Lowe's, Home Deopt and probably many hardware stores. Hope this helps.
@@Sparky-ww5re no I had some 10-3 laying around I'm just not going to use one of the wires but I didn't know I have to use a disconnect at the water heater, like I said I was hoping I could make a direct run put a box in the ceiling and then flexible steel conduit to the water heater
Is shielding code ??
Are you trying to kill people? You say you need a cut off for the hot water heater and you show a basic light switch? You do know that's not rated for 240, right? You also should know that if you're running that on 240 and people use such a switch, they're only shutting off part of the power to it? I rarely complain, well I do, but I don't say that's dangerous, but that's dangerous.
You cannot use a regular light switch like that as a cut off for a hot water tank. People see that and will try it. Then they will get a nasty shock... if they're lucky.-
It's a motor rated switch, not a normal switch