Tankless hot water heater install/conversion advice

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doc1623

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Advice on temporary install of a tank-less hot water heater please. It's temporary, because I'm going to leave the drywall off for sometime so I can do electrical and more later and I think I need to braze copper long term to come out of the wall (let me know any non-brazing solutions). I have a filter (pic below) that's supposed to help reduce hardness and braided hoses. I have two of the compression shutoff valves that you see.

The shutoff in there now is sort of wrong. Sort of, because I can use it but I think I need to have copper on both sides instead of just one to use these. I was hoping to go compression on the copper side to NPT but I didn't do right, and bought compression to compression shutoffs (online). I have several hoses one of which has male npt on one side and female on the other. I think, I just need two female compression to male NPT adapters but if it's best, I can buy new shutoffs, if they come like that. I've seen "kits" but they seem kind of high.

This says "vent-less" but again lmk what you guys think.
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My house is a 77 and it was a small/cheap house. It has a "water wall" (I stole this term from the Matrix movie). All the water is in one wall and that wall has a gap you can see in the attic. One side is my kitchen sink dishwasher then the washer/dryer and on the other is the guest bath then my bathroom. I'm putting in a tank-less I bought years ago (I hope it works). I'm going to find a curtain to go over the "closet/washroom" (I hate the harmonica type doors that were on there).


What it was:
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Reach4

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Advice on temporary install of a tank-less hot water heater please. It's temporary, because I'm going to leave the drywall off for sometime so I can do electrical and more later and I think I need to braze copper long term to come out of the wall (let me know any non-brazing solutions). I have a filter (pic below) that's supposed to help reduce hardness and braided hoses. I have two of the compression shutoff valves that you see.
1. Soldering (sweating) is easier than brazing, and is much more common. Also, press connections are becoming even more common. They need a tool, but there are advantages including no fire.

2. Braided hoses are really a metal braid over a rubber-like tube. Some of these produce black stuff into the water. Corrugated copper or stainless flex lines do not have that problem. https://www.plumbingsupply.com/flexes.html https://www.supplyhouse.com/sh/control/search/~SEARCH_STRING=falcon corrugated

3. I think compression fittings take more torque than a lot of people expect. Use longer wrenches and always use two wrenches. Also, lube the ferrule and threads with silicone grease or pipe compound. That makes it easier to tighten things down, and for the metal to flow as you compress the ferrule.
 
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doc1623

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Electric tankless? You must have a large electrical panel?
It requires a 50 amp CB. I put it in but am waiting on the 6/2 electrical cable I ordered. Thankfully, it won't require much length. You can see in the pick all the wires going directly to the CB panel on the other side of the wall (outside)
 

John Gayewski

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It requires a 50 amp CB. I put it in but am waiting on the 6/2 electrical cable I ordered. Thankfully, it won't require much length. You can see in the pick all the wires going directly to the CB panel on the other side of the wall (outside)
I don't think your gonna get much hot water from 50amps. There's some math one can do to figure it out. Luckily in Texas the water temp coming in is probably above 50.
 

doc1623

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1. Soldering (sweating) is easier than brazing, and is much more common. Also, press connections are becoming even more common. They need a tool, but there are advantages including no fire.

2. Braided hoses are really a metal braid over a rubber-like tube. Some of these produce black stuff into the water. Corrugated copper or stainless flex lines do not have that problem. https://www.plumbingsupply.com/flexes.html https://www.supplyhouse.com/sh/control/search/~SEARCH_STRING=falcon corrugated

3. I think compression fittings take more torque than a lot of people expect. Use longer wrenches and always use two wrenches. Also, lube the ferrule and threads with silicone grease or pipe compound. That makes it easier to tighten things down, and for the metal to flow as you compress the ferrule.
Wow, thank You!
That's a lot of great information.

1. I'll try the soldering when the time comes. The braided hoses are more temporary and the hot water won't be consumed but I will plan on changing them out. At this point, I need hot water, and I need to make sure the unit works. Also, I plan on leaving the drywall off for some time because of the electrical access and the access to my tubs old fashioned hot, cold, and shower valves with those rubber seats that I hate.

2. I do have one copper corrugated line from the habitat-restore (new). Would you preference between stainless and copper?

3. I need to save your advice for the future. I had to re-tighten some of these until they stopped leaking before I saw this.

The only issue I have left (for the temp plumbing setup) is the filter housing T. I may try once more before buying new teflon tape. I remember (too long ago), in the military, making a hydraulic hose and it kept leaking even though I thought I had it down. I had a senior come in and try with the same results. He then said we need to try new tape. I did it with new tape that stretched better and it worked (didn't leak). This was a 3k psi hose; so, not normal plumbing. Does old tape effect normal plumbing?

Lastly, I don't mind using this "filter" for now but it's rather odd. The T doesn't force all water through the filter. I'm guessing there are better filters for protecting hot water heaters. Recommendations?

Again, thank you for all the great info!
 

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Fitter30

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It requires a 50 amp CB. I put it in but am waiting on the 6/2 electrical cable I ordered. Thankfully, it won't require much length. You can see in the pick all the wires going directly to the CB panel on the other side of the wall (outside)
50 amps x240 vac = 12,000 watts x 3.41 btu per watt= 40,920 btu' s
Not much even for a shower.
 

doc1623

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First,
50 amps x240 vac = 12,000 watts x 3.41 btu per watt= 40,920 btu' s
Not much even for a shower.
I had it wrong. I did post this, but it's two 50 amp double-pole breakers. well, I said dual instead of double pole
 

doc1623

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I got it installed and it's leak checked!

Again, this is a temporary measure, for a while, until I do other work e.g. electrical and can redo the drywall and copper later. Plus, I need to ensure the unit works.
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doc1623

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This breaker box seems a bit different the top half is normal, but the bottom half is feed via two 50 amp circuit breakers from the top (the bottom right of the top set). That's most clear in the second pic, I think. I moved the 30 amp one you now see in the top left of the lower set from the top left of the upper. I think when they installed the new A/C a few years ago they put that there; I don't know why as it's two the clothes dryer, but I guess they were moving stuff. You can see the two dual 50 amp breakers that will be for the hot water heater on the top left (first two on that left upper side).

The old sticker is long gone. I need to map it but I haven't. All the outlets and lights are on the bottom. The top is A/C, Electric stove. I don't know offhand what the right upper dual-pole 30 is for; maybe the clothes washer?

Anyway, I appreciate all thoughts and advice. Eventually, I want to redo this breaker box completely but I don't have the funds right now. So, it's what I have.

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I tried to search for the breaker box model but search engines seem more worthless now. I think I've found it in the past, but I had trouble this time.


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Reach4

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I think the upper breakers are 1 inch wide regular breakers.

I think the lower breakers might be THQP tandem breakers. The breaker to the left of the "Push to test" breaker confuses me a tad if the two handles are tied together. If the two handles are not tied together, then one white is being used as an independent hot. Those tandem breakers are space savers, putting two breakers into a 1 inch space.

The breaker with "Push to test" has a GFCI built in.
 

doc1623

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Finding room here seems like it will not be fun but you can see some concrete I can try and remove in the first pic.

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Fitter30

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5)0 amp breaker #6 wire. Last pic with wires going through that ruff edge hole a accident waiting to happen. Post 15 pic left side large black wire that insulation looks funny like a snake losing it skin. Your electric.panel looks to be a split buss they been obsolete for years. With a tankless water heater your going to need 400 amp panel.
 

doc1623

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5)0 amp breaker #6 wire. Last pic with wires going through that ruff edge hole a accident waiting to happen. Post 15 pic left side large black wire that insulation looks funny like a snake losing it skin. Your electric.panel looks to be a split buss they been obsolete for years. With a tankless water heater your going to need 400 amp panel.
I think your right but for now, I may have to make do. I simply can't afford that now. At least, I'm within the manufactures minimum recommendations. I grant you that they are very low and don't seem to consider much. I chipped away at that concrete and found the conduit that I could see from the inside. Unfortunately, the house builder's didn't align the conduit with the box well. I'll post a pic later. I think that's why they added the cement i.e. just to cover their screw up. I did remove some of that (paper?) insulation as well. For now, running those cables through the wall is my biggest challenge; I hope I have room without either moving the box up like half an inch, or having to cut/widen the hole in the box itself.

You can see my units information in the installation manual https://www.stiebel-eltron-usa.com/sites/default/files/pdf/install-tempra-tempra-plus.pdf
I have the 24B. I believe, the only difference between mine and the plus, is the digital display (mine doesn't have it).
 
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doc1623

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I have a 20 year old home with a 30 gallon standard electric water heater. I want to change to a tankless electric water heater. Can I just select any tankless and have it installed or do I need to plan on significant plumbing and electric service modifications? Will the existing electric connections be adequate? Understand there will be minor plumbing necessary. Hoping to gain space where the tank is located. What kind of costs are likely? Two person home.
I bought my tankless years ago, and I didn't do it right. You might call for a quote and see what they have to say. In my case, I hated to it, simply because I don't have the money to pay for it being professionally done now, but my existing hot water heater went out and I thought, I could "just" switch over. At this point, it's my only alternative to get hot water without a very large delay. I thought this would work before researching or starting but even if it does, it'll be "hacky", at least for a while but like @Filtter30 has mentioned, most of us probably need to upgrade our main breaker box, at least for a whole house solution, but maybe even just for the shower (from what people have said). You will need more than 50 amps and it will most likely require TWO dual-pole circuit breakers (which take up two spaces each) and two very large wires. From what I understand you want the wire to exceed the CB capacity e.g. 6/2 is rated for 55 amps while 8/2 is only rated at 40 amps. My house is very small with very short distances from the heater to all water outlets (the furthest is like 10ft), even for it's small size (all on either side of one short wall ~16ft) and I live in an area which has high ground water temperature (in theory, I haven't measured), which may be ideal, and it's been anything but simple (at least for me). The hot water does go back in the slab for the furthest outlets. If I stated anything incorrectly, please correct me.

If you just read through mine you will see, it won't be that simple. I know there probably some very qualified electricians here, but I might try to find an electrical forum as well. Please let me know anyone knows a good one.

Personally, if you need to check yourself without a professional estimate. I would first check your main circuit breaker panel (and any sub-panels for ratings). I can't seem to find mine anywhere, but yours is younger and you might have better luck. I wish I had checked first. Second, if you have enough spare capacity (I'm just trying and it might not be great) both in power and in CB slots. I barely have enough space and I'm not sure how well it will work. My tank was a 40 gallon. As far as which unit you need you can check the brands recommendations. Mine is like this. Hopefully, I have more than enough even in the coldest of winters. I think so, but it seems to depend on your baseline temperature and GPM usage. Again, feel free to correct me if needed.
 
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doc1623

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I think the upper breakers are 1 inch wide regular breakers.

I think the lower breakers might be THQP tandem breakers. The breaker to the left of the "Push to test" breaker confuses me a tad if the two handles are tied together. If the two handles are not tied together, then one white is being used as an independent hot. Those tandem breakers are space savers, putting two breakers into a 1 inch space.

The breaker with "Push to test" has a GFCI built in.

The upper are dual-pole (2 inches each), unless I'm very much mistaken. They are for the largest voltage and amperage requirements all require 240v i.e. electric stove, internal and external heat pump units, and the dryer. In the pic on the bottom of the left is the stove (dual-pole 50), then on the top of the right side is the external heat pump unit (dual pole 30), then next on the right side is the internal heat pump unit (dual-pole 50), then the bottom right of the upper is the CB for the lower portion (dual pole 50). So, as I understand it, the bottom acts like a 100 amp sub-panel

You can basically ignore the gfi breaker, it's for nothing special. Who knows who put that in or why. It's to a spare bedroom light and probably at least one socket.

I believe, I only have one tandem breaker. I think the A/C guys used that for my dryer while shuffling things around. It's the 30 amp (on the bottom upper left in this pic). I had it in wrong. I don't know if it's wrong but it was taking up two one inch slots on the upper left side (but not fully, as it left a .5 space above and below). I had to move it from where I put it in this pic to go across two 1 inch spots on the bottom (leaving .5 above and below as before), so it could get the full 240v the dryer needs. This is where I may run into capacity problems, but worse comes to worse, I can turn off other CBs to run the dryer. I ran it the other day without issue, but we'll see. I do need to replace it with a dual pole 30, I think, as it seems hacky as it is, but I'm not sure. Please let me know, if someone knows better.

Apart from the dryer CB and the GFI the bottom are all single .5 inch breakers.
 
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Reach4

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The upper are dual-pole (2 inches each), unless I'm very much mistaken. They are for the largest voltage and amperage requirements all require 240v i.e. electric stove, internal and external heat pump units, and the dryer.
You are right... I was thinking about the one inch space per pole. Alternate 1-inch positions connect to different hots, and a 2-pole breaker takes up two spaces.

I was right about the tandem breakers... that is what they call them. Two independent breakers for independent 120 volt circuits fit into one 1-inch space.
 
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