How to proceed with tankless water heater problem?

[secondcor521]

Hi all.

I have an electric tankless water heater in my house.  It's an ESI 2000, the company is out of business, but their product still works.

Well, mostly still works.  It stopped producing hot water the other day, which it does every 7-10 years because we have hard water and I have never installed a water softener like I probably should have.

The fix is to remove the flow sensor, clean it with vinegar / CLR, and reinstall.  I did that, and in the process of putting things back together, I have both (a) broken the flow sensor a bit, and (b) created a leak on the input line.  I think I have (a) solved, but I need to fix (b) as well to make sure.

There is a tiny hexagonal nut on the side of the input / supply line, and this has two small black wires going through the center of the nut into the supply line.  The hole through which the black wires run appears to be sealed with some sort of white paste.  I have disturbed this white paste and now it leaks through that hole when I open the water supply valve.

What is this white paste, and how do I fix this leak?  I'm assuming it's as simple as knowing what it is, buying some from the local plumbing supply store, and applying as directed.

It's about the color and consistency of that white diaper rash ointment we used when my kids were babies 20 years ago.

And whatever the stuff is, it was holding back my city water supply line, which is I think somewhere around 20-30 PSI, maybe more.  Now, however, even opening the supply valve a little, it's spraying water everywhere.

Thanks for any assistance!

[secondcor521]

Attached image.  You can actually see a water drop leaking out and pooling.

ETA:  Up is to the left.  I'm not sure why the picture is rotated counterclockwise 90 degrees from reality.

[Omy]

I think it's called plumber's dope (not plumber's putty). I'm not a plumber, but I've heard the term before.

[secondcor521]

Thanks!  That was one of Google's suggestions too.  I'll pick up some today and see what happens.

[secondcor521]

Update:

Ended up calling a professional plumber because I was concerned that my homeowner DIY repair might result in a leak in the middle of the night or on a weekend and flood the house.

They came out and analyzed the situation and said that the leak is probably due to the broken flow sensor, not due to missing white stuff.

The flow sensor manufacturer sells them, but only to distributors with a minimum quantity of 5, and the flow sensors are about $200 each.

I've considered my options and narrowed them down to two:

1.  Buy 5 x $200 flow sensors = $1000.  Fix my 20 year old water heater (probably).  Plus $125 for the plumber call, and I'm out $1,125 and have a probably working 20 year old electric tankless water heater.  Maybe sell the other four on Ebay or keep them for spares.

2.  Buy a new electric tankless and have it professionally installed.  The plumber who did the initial call thinks it's $3K to $4K.  I would get multiple quotes, I'm guessing I could get someone to do it for about the $3K number.  I'd have a new water heater that would work.  Again, plus the $125 for the initial plumber call.

As I write those out, I'm leaning towards option 2.

For completeness, options I've ruled out:

1.  Living without hot water.  I'm not keen on it, nor are the other current residents of my house.  Probably not reasonable to go without hot water for dishwashing and clothes laundering, and showers.

2.  Getting the distributor to buy 5 and sell me 1, even at a high price.  Distributor said they wouldn't do it.

3.  Buying a newer flow sensor and trying to get the old water heater to work with it.  Primarily I ruled this out because I don't have any specs on what the water heater expects on that sensor, and I think a mismatch would possibly cause serious problems.

4.  Installing a regular water heater.  House isn't plumbed / set up for this.

5.  Installing a gas tankless water heater.  House isn't plumbed / set up for this.

Thoughts and opinions welcome.

[daverobev]

Have you tried other places to get the flow sensor - like a larger plumber who might have a few of them? Or ebay? Refurbished one? Etc.

Seems a bit... much... to spend $3-4k to replace the unit if a part can be replaced.

[curious_george]

Option 3:

Go buy an eco smart electric tankless water heater off of Amazon for 200-400 dollars and install it yourself.

Electric tankless water heaters are dead simple to install. I even ran new circuits and breakers for mine and it's been running great for like 10 years or so.

You can do it. :)

[secondcor521]

Have you tried other places to get the flow sensor - like a larger plumber who might have a few of them? Or ebay? Refurbished one? Etc.

Seems a bit... much... to spend $3-4k to replace the unit if a part can be replaced.

Yes, I've tried several things.

The original manufacturer still technically manufactures them but hasn't sold any recently to any of their distributors.  The distributor for my region doesn't have any and refuses to buy 5 just to sell me one.  Ebay doesn't have the exact model.

The main problem is that the water heater doesn't provide any specifications as to what the flow sensor input needs to be.  All I have is the (broken) flow sensor with the part number on it, and I can see how big it is and what kind of connector it plugs into.

I suppose what I could try (and maybe will) is to call the manufacturer back and ask them if they have the spec sheet on the old part and if I could find any newer part in the series that could work as a substitute.

The key issue that concerns me is that the flow sensor appears to turn the flow rate in GPM into electric pulses at a certain rate.  I'm sure the water heater uses that pulse rate to learn the GPM and decide how much power to add to get the water to the correct target temperature.  If the GPM <-> pulse rate differs between the old sensor and the new one, then the power applied will be off, and the water will either be too cold or too hot.  There's probably some acceptable variability, but I'm not knowledgeable enough to know for sure.

Part of the price gets me a new vs 20 year old water heater.  Part of it gets me hot water again.  Part of it fixes the problem of having an existing water heater where the manufacturer has gone out of business.  Part of it saves me having to buy a $200 replacement part.  So there's value to the $3K compared to just the part.

[secondcor521]

Option 3:

Go buy an eco smart electric tankless water heater off of Amazon for 200-400 dollars and install it yourself.

Electric tankless water heaters are dead simple to install. I even ran new circuits and breakers for mine and it's been running great for like 10 years or so.

You can do it. :)

I've thought about that too.  I can do all of it except the electrical hookup part.  Electricity scares me though because I really don't understand it well.  I suppose I could just hire an electrician for that part.  (There is already existing wiring but it's only two, uh, branch circuits I think and I might want a model that uses three.)

I'm looking at the Eco Smart and the Stiebel Eltron brands.  Any ideas why the former is half the cost of the latter?

[curious_george]

Option 3:

Go buy an eco smart electric tankless water heater off of Amazon for 200-400 dollars and install it yourself.

Electric tankless water heaters are dead simple to install. I even ran new circuits and breakers for mine and it's been running great for like 10 years or so.

You can do it. :)

I've thought about that too.  I can do all of it except the electrical hookup part.  Electricity scares me though because I really don't understand it well.  I suppose I could just hire an electrician for that part.  (There is already existing wiring but it's only two, uh, branch circuits I think and I might want a model that uses three

I'm looking at the Eco Smart and the Stiebel Eltron brands.  Any ideas why the former is half the cost of the latter?

You know - that's a good question and I honestly have no idea why.

I took a chance on the eco smart about 10 years ago and it worked out great for me.

If you aren't comfortable with electricity then it might be a good idea to get a few different quotes for tankless electric water heater install. 3-4k sounds steep to me...

[ChpBstrd]

For completeness, options I've ruled out:
...
4.  Installing a regular water heater.  House isn't plumbed / set up for this.

I know you mentioned this as ruled out so people like me wouldn't ask questions, but can you explain this point more?

Was the house built without a full size water heater closet? Does it have an attic or basement? Could you just install a freestanding traditional $600 WH in a laundry room or something, at the cost of some storage space? Is it a tiny house we're talking about?

When we're talking the $3k range, you can generally move a standard WH anywhere it fits.

[secondcor521]

For completeness, options I've ruled out:
...
4.  Installing a regular water heater.  House isn't plumbed / set up for this.

I know you mentioned this as ruled out so people like me wouldn't ask questions, but can you explain this point more?

Was the house built without a full size water heater closet? Does it have an attic or basement? Could you just install a freestanding traditional $600 WH in a laundry room or something, at the cost of some storage space? Is it a tiny house we're talking about?

When we're talking the $3k range, you can generally move a standard WH anywhere it fits.

Mostly mentioned it just so people would be aware that I had at least thought about it.  Certainly a fair question and reasonable to discuss.

Around here it is very normal and typical to have the water heater and HVAC system in a corner of the garage.  My house is atypical in that it was built originally with the electric tankless designed into the build.  The tankless water heater is in a recessed area in the laundry room wall.  So there is (a) space in the garage that could be repurposed for a water heater but it's really intended to be for a water softener, and (b) the hot water side of the plumbing system is plumbed into the recessed cavity in the laundry room, which is also where the water supply line is plumbed to, plus (c) there is electrical wiring and circuit breakers already set up to that cavity.

I don't like the idea of an ordinary water heater in the attic, although I know that is done in parts of the country.  I could put it in the garage, but that would prevent me from having room for the water softener (which I do actually want to add at some point).  The laundry room is too small for a regular sized water heater.  And no basement, just a crawlspace which is too shallow and the access areas are too small to get a tank down there.

And in all cases, the plumbing would have to be rejiggered, which I realize is probably not that big of a deal.

[secondcor521]

I suppose what I could try (and maybe will) is to call the manufacturer back and ask them if they have the spec sheet on the old part and if I could find any newer part in the series that could work as a substitute.

I did send a message to technical sales requesting help on this.

In parallel am getting quotes from two to four plumbing places.

We'll see.

[ChpBstrd]

For completeness, options I've ruled out:
...
4.  Installing a regular water heater.  House isn't plumbed / set up for this.

I know you mentioned this as ruled out so people like me wouldn't ask questions, but can you explain this point more?

Was the house built without a full size water heater closet? Does it have an attic or basement? Could you just install a freestanding traditional $600 WH in a laundry room or something, at the cost of some storage space? Is it a tiny house we're talking about?

When we're talking the $3k range, you can generally move a standard WH anywhere it fits.

Mostly mentioned it just so people would be aware that I had at least thought about it.  Certainly a fair question and reasonable to discuss.

Around here it is very normal and typical to have the water heater and HVAC system in a corner of the garage.  My house is atypical in that it was built originally with the electric tankless designed into the build.  The tankless water heater is in a recessed area in the laundry room wall.  So there is (a) space in the garage that could be repurposed for a water heater but it's really intended to be for a water softener, and (b) the hot water side of the plumbing system is plumbed into the recessed cavity in the laundry room, which is also where the water supply line is plumbed to, plus (c) there is electrical wiring and circuit breakers already set up to that cavity.

I don't like the idea of an ordinary water heater in the attic, although I know that is done in parts of the country.  I could put it in the garage, but that would prevent me from having room for the water softener (which I do actually want to add at some point).  The laundry room is too small for a regular sized water heater.  And no basement, just a crawlspace which is too shallow and the access areas are too small to get a tank down there.

And in all cases, the plumbing would have to be rejiggered, which I realize is probably not that big of a deal.

Thanks for the reply. I was really curious about the layout.

I almost went tankless at my house until I read the reviews. LOTS of people have problems with these because the general idea is to concentrate a shitton of energy into a very small area of metal, thereby causing lots of metal flexing and fatigue. Then there are the high-wattage circuit boards which can toast. The stories of people getting only a year or two out of very expensive equipment are so common that I was persuaded to sacrifice storage space to go with a tanked WH. Your example of getting 20 years out of a tankless unit seems to be a real outlier. There are also people who get lots of years out of tanks, and this seems to involve changing the anode rod every 5 years or so.

In your situation, I'd be tempted to build a heavy-duty metal shelf in the garage and/or hang a short, tanked WH from the ceiling joists. The hood of the car could then somewhat tuck under the WH. I don't like the idea of attic plumbing anywhere it might freeze, but OTOH garage installations make the most sense to me because there's just a concrete floor for any leaks/overflow to land on. The downside of such a creative design is you'll want to leave a couple feet between the WH and ceiling so that you can access the anode rod every few years.

Or... you might trade places with the water softener going on the shelf and the WH going where the softener was.

[secondcor521]

Follow up:

Never heard back from technical sales on the flow meter.

Got tired of not having hot water in the house.

Bought a Stiebel Eltron Tempra Trend 29 off Amazon for about $650, then spent another obscene amount with a local, highly rated plumbing/electric company to remove the old one, install the new one, and also install an additional garage circuit for an unrelated project, and adding one outlet in the attic for an attic fan.

I was half tempted to go into the plumbing/electrical business as I think they must be doing ridiculously well based on their pricing structure, but will not because (a) it's work, and (b) there are arguably quite high and unknown overhead costs (fully stocked vans, a parts warehouse somewhere nearby, dispatchers, technicians).  Also, in the grand scheme of things, it is not much money and QOL is improved.

Thanks all for the suggestions and comments.