Electric Water Heater Piping

I am working on my pre-licensing classes for Florida and have a question about the picture here. This is a picture of the water heater in my house. It is electric and the plumbing system is PEX. My question is, what is the topmost pipe, coming from the top of the cold water supply pipe? It goes into the wall, wiggles a little, but seems to be secured to something.

I also see, not pictured, that the circuit breaker for the water heater is 2 30 amp breakers clipped together, which makes it a 60 amp breaker. We just had the electric panel redone a few months ago and it passed code. I thought water heaters were supposed to be on 30 amp breakers.

You would want to provide a photo of that as well. 2 -30 amp breakers clipped together does not equal 60 amps. You will also want to research the water heater min and max breaker requirements from the manufacturer.

1 Like

Hi Brian,
Thanks for your quick response. I included photos of the breakers, which is actually 3 (#11, 13 & 15), and the legend. Two groups of double poled breakers but one of the four is a different appliance, yet clipped together? I also included a pic from the user’s manual of the circuit sizing guide and the label with wattages.

Sorry for the newbie questions, but if I can’t understand my own house when I have no time limits and no pressure, I feel like I’ll be doomed in the real world.


Branch Circuit Sizing Guide

Your water heater is using 2 - 120 volt circuits to obtain the 240V needed to operate (hence the connected breakers). Based on your chart, the max fuse would be 25 amp. But, you must look at the manufacturers installation instructions as well. Which can be found online.

However, in my opinion, the 5 amp upsize to 30 is negligible and is something I see often. It may be intended to reduce nuisance tripping. I am sure an electrician will come yell at me, but it is not something I call out.



Now, for homework. Go find out what this is connected to and where is discharges. Take pictures. Also, any markings on the device at the top.

1 Like

Yeah, I am going to make it a mission to figure out what’s going on here. Thanks for all your help!

1 Like

Good luck, that is how it is done. There are no shortcuts. This desire to understand will help you be a notch above.


Also, post a pic of the TPRV and drain pipe.


There you go Jeff. Too bad the drainpipe discharges into the pan.

1 Like

And where does this go? Water heaters are fun…and always more than people bargain for.

1 Like

Exactly. It goes into the pan and then onto the garage floor, probably into the living area of the house and not down and out to the driveway, cause, you know, luck. Pretty lazy homeowner to not fix it even when he knows it’s wrong. Oh wait, that’s me.


The panel directory is incorrect 9&11 are one 240 volt circuit and 13&15 are another 240 volt circuit. Both circuits are 30 amps, 240 volts. A 30 amp branch circuit is permitted for a 4500 watt HWH at 240 volts.


Good advice from everyone above. I’ll add: Is an expansion tank required in your area?


@msmith104 - Did the previous seller attempt to have some sort of a recirculation pump installed? In other words, you get hot water quickly at a faucet and do not have to wait for the water to heat the pipes?
This is not how one is traditionally done or connected, but people do things uniquely all of the time. You may see some sort of smaller softball sized pump under a sink or in a crawlspace or attic. It would generally pull off of the heated side of the water heater, but that may be a return loop from the recirculation pump that is remotely mounted and pulling water from a hot supply at the far end of the house…to reiterate, not how I normally see them installed, but a possible answer. There is an install sticker at the top. If you cannot figure it out, call them and ask!

Thanks for the suggestion. I will be checking it out this weekend.

Good question Burt. I hope not, I don’t have one!

Great questions and answers here from the best. Love to read these to get meaningful info.

1 Like

Here’s the applicable NEC sections and calculations related to sizing the branch circuit for this HWH.

Minimum Branch Circuit Size:
4500 watts/240 volts = 18.75 amps*125% (for continuous load {422.13}) = 23.4 amps, 25 amp minimum branch circuit size.

Maximum Branch Circuit Size:
18.75*150% = 28.1 amps, next standard OCPD size 30 amps {422.10.(E)(3)}

422.10(E) Single Non–Motor-Operated Appliance. If the branch circuit supplies a single non–motor operated appliance, the rating of overcurrent protection shall comply with the following:
(1) Not exceed that marked on the appliance.
(2) Not exceed 20 amperes if the overcurrent protection rating is not marked and the appliance is rated13.3 amperes or less; or
(3) Not exceed 150 percent of the appliance rated current if the overcurrent protection rating is not marked and the appliance is rated over 13.3 amperes. Where 150 percent of the appliance rating does not correspond to a standard overcurrent device ampere rating, the next higher standard rating shall be permitted.


A thermal expansion tank or device is required in most jurisdictions for a “closed water system”. Determining if the subject home is on a closed system is sometimes not possible. One way devices such as back-flow preventers and pressure regulators will create a one way or “closed water system”.

I have this narrative to share.

Water heater did not have a visible thermal expansion tank or device which is recommended for a “closed water system”. I was unable to conclusively determine if the water supply was an “open or closed” system and such determination is outside our standards of practice. Thermal expansion can create a rapid and dangerous pressure increase in the water. Recommend further evaluation and the installation of a thermal expansion tank or device as needed by a qualified plumbing contractor.

Here is a good article explaining thermal expansion and thermal expansion devices.



Hi everyone,
Thanks for all the great insight. I can tell I have chosen a great group of people to be affiliated with. I have been checking into the mystery in my OP. I checked my attic and bathrooms for a recirculation pump and found nothing. No sign of an expansion tank anywhere either. My real mystery is the seemingly extra cold water pipe running into the wall.

I have included some photos with labels if anyone wants to have a look and chime in again. Luckily, this is my house. I would hate to have to stand in front of a client and be totally clueless as to what is going on here.