Just finished a tankless water heater install

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Alexb2000

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Alexb2000
I just finished up a tankless hot water heater install this weekend. For once the timing worked out well and I was able to do the roof work on the last semi-warm day and then finished the plumbing just before we had a little freezing rain.

Good points: I gained a nice little closet to store some tools and pool supplies. The wife is ecstatic never worrying about running out of water. The temperature is always consistent vs. tempered in a tank heater. We are on natural gas so I don't expect a world of savings, but it's nice to use zero when we are away for three weeks.

Bad points: Cost will never pay back unless natural gas prices go crazy. The heater and venting was $1100, misc. piping $400, and another $30 in hardware. Nothing from your old heater is reuseable, this isn't a rip and replace by any means. In my case it also took about 15 hours of labor vs. about an hour for a normal heater.

This is one of two, I will definetly replace the other tank heater with a tankless when the time comes.

Anyway I thought it might be interesting to discuss in case anyone is considering it.

Here is a picture just after startup, still have to insulate and button everything up.
 

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I like it! A 'normal' water heater works fine in our house, but I want something to use down in the shop. Right now, the shop isn't heated or insulated and average winter temps are in the high 20's.

We are all electric here and only pay 3 cents per kw/h.

I wonder if this would be an option for hot water in the shop?
 
DeeG said:
I like it! A 'normal' water heater works fine in our house, but I want something to use down in the shop. Right now, the shop isn't heated or insulated and average winter temps are in the high 20's.

We are all electric here and only pay 3 cents per kw/h.

I wonder if this would be an option for hot water in the shop?
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I have an electric tankless on my shop sink. Cost me $120 10 years ago. The shop in winter goes well below freezing. No problems and nice hot water anytime. The electrics are super easy and quick to put in.
 
We also have a tankless in the bathroom at the yard. Very low cost and easy install.

Alex, mark your calendar to give us a follow up in late Feb or March after we are done with the winter freezer. I'd hope to hear if any "boy it was nice to have..." stories offset your "never will pay us back unless NG price go crazy" statement.
 
I have a similar Rinai (also the same FIOS battery backup). I would strongly suggest you install an additional duplex receptacle there rather than relying on the bogus cube tap. If this is in an area exposed to whether you should use an "in use" style cover. Otherwise, you can just remove that bogus cover that's getting in the way.
 
AggieMike88 said:
We also have a tankless in the bathroom at the yard. Very low cost and easy install.

Alex, mark your calendar to give us a follow up in late Feb or March after we are done with the winter freezer. I'd hope to hear if any "boy it was nice to have..." stories offset your "never will pay us back unless NG price go crazy" statement.
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Oh I'm already really glad I did it. Our master has a LARGE tub with granite surround on an exterior wall under a window. The thermal mass when it's cold takes a lot to heat up. It was almost like you had to fill the tub twice during a bath which is my wife's Sunday ritual. Anyway, problem solved you can run hot water forever now and keep the tub really hot. No more turning on the hot only to get tepid water out. Not to mention this heater should last well over 20 years vs. 9 I got from the one I replaced.
 
flyingron said:
I have a similar Rinai (also the same FIOS battery backup). I would strongly suggest you install an additional duplex receptacle there rather than relying on the bogus cube tap. If this is in an area exposed to whether you should use an "in use" style cover. Otherwise, you can just remove that bogus cover that's getting in the way.
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Already working on it. That was just to get some hot water going. threading black pipe by hand for two days gave me all I wanted at that point.
 
How is the water heat level and water pressure? I am considering one but like my shower HOT and coming out like a fire hose.

Screw the low flow heads and saving the fish...I want a good shower!
 
I looked into tankless before I replaced one of my commercial water heaters a few years back. For high yield applications one may require multiple tankless water heaters in series. Just like regular water heaters there are many different units with differing capabilities. You need to look at rated flow rate and temp rise. In some parts of the country and some times of the year incoming water temp will be very low.

I did install a propane tankless water heater in our 5th wheel. It works great when it works. We have seen a couple occasions where the flowmeter failed to sense water flow and thus failed to turn on the heat. For the most part though, we see endless hot water and at a temperature higher than one would ever want or need.
 
Shawn said:
How is the water heat level and water pressure? I am considering one but like my shower HOT and coming out like a fire hose.

Screw the low flow heads and saving the fish...I want a good shower!
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No difference in pressure. IMO a lot of this is making sure you have the right sized heater. Mine is 7.5 GPM at a 60 degree rise servicing only two bathrooms. Showers have to flow less than 2.2 GPM (most are 1.5ish) so even with both going I have plenty of reserve. These complaints are usually due to under sizing by contractors trying to be low price.

Temp is perfect, mine is set to 120 (default 110)and the water is exactly 120 as long as you run it. We're all so use to the hot water tempering during a long shower, or spiking after a toilet flush, or... That it seems impossible for the hot tap to run all day with zero fluctuation.

The other thing that doesn't make sense in a tanked heater is heating the water to ~140-160 and then mixing it with cold at the faucet. Lots of wasted energy there. Tankless can be set wherever and it stays without the chance of scalding. Not a big risk in our house, but a plus if there were kids around.
 
We have a condo in Hawaii that I put one in. 2 years later had to pull it out. It was great for water saving and especially space savings, but the mistake I made was not putting a filter on the inlet side. Over time, the mineral deposits build up in the heating elements and render the heater ineffective.
 
WoooPigSooie said:
We have a condo in Hawaii that I put one in. 2 years later had to pull it out. It was great for water saving and especially space savings, but the mistake I made was not putting a filter on the inlet side. Over time, the mineral deposits build up in the heating elements and render the heater ineffective.
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If you look at the picture I have flush valves installed so I can recirc. Some vinegar through every so often. Did your install not have those?
 
Smart man. No I didn't install flush valves either.

All's not lost though. I kept the unit and filled it with CLR, let it sit for a day, flushed it out, and the elements looked good as new on the inside. So I put it in our little hunting cabin in Arkansas. Put a filter on the front side and keep it changed a couple times/year and it's worked like a charm for a year now.

But yes, I highly recommend anyone that DIY's this to use a good filter/flush valve (combo even) because they do not tolerate mineral deposit the way a water tank heater will.
 
Shawn said:
How is the water heat level and water pressure? I am considering one but like my shower HOT and coming out like a fire hose.

Screw the low flow heads and saving the fish...I want a good shower!
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My Rinnai works great. Yes you must size it so that all the potential simoultaneous users are handled. That has not been a problem with my unit even with two using showers and the washer running (and who knwos what else).

The temperature is adjustable on the front panel (I even have a remote). I like my showers hotter too so I jack mine above the default setting as I do with the tanked hot water heaters as well.

The nice thing is it NEVER RUNS OUT. You can shower all afternoon and it will still be as hot as it was when you started.
 
On our regular water heater we have to pull the anode rod so they don't last as long as they should. I've thought about installing a tankless but wasn't sure if our very irony water would destroy it too. We already filter but quite a bit gets through anyway. I love the idea but would hate to replace it every few years.
 
My uncle has one, and the one beef I have is that low flow rates will not enough to allow the heater to turn on. Like, using the spray head in the kitchen to rinse, you either get warm water with a harsh spray that bounces everywhere off the dishes (so much for water conservation), or a gentle rinsing spray with cold water.
 
We have a lot of iron in our water and in five years we've not had a problem. It's propane fired so heating elements aren't an issue. I do have an iron filter ahead of it.
 
I looked into this a while ago, and since we do not have natural gas to our neighborhood quickly dismissed the idea. I think it is a good solution however, especially if you use a lot of hot water.
 
Alexb2000 said:
The other thing that doesn't make sense in a tanked heater is heating the water to ~140-160 and then mixing it with cold at the faucet. Lots of wasted energy there. Tankless can be set wherever and it stays without the chance of scalding. Not a big risk in our house, but a plus if there were kids around.
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I believe you're using some flawed logic there. You're not wasting energy by tempering the hot water with cold, you're simply using less hot water to achieve the desired temperature.

Besides, traditional water heaters don't have to be run that hot. Mine's set on 125 and we have plenty of hot water, but ere are only two of us.

The waste comes with keeping 40 or 60 gallons of water hot all the time...kinda like not putting your furnace on night set-back is more expensive than setting back and throwing an extra blanket on the bed.

Re: instantaneous heaters, as some have already addressed, many of them are quite sensitive to hard water issues. O'Reilly puts instantaneous in all their stores. In hard water regions the WHs typically don't even last through the warranty period (i.e. one year). They'd replace it once. Then, when the second one failed shortly thereafter, they'd replace it with a 5 gal electric WH. They went though about 4 or 5 different brands while I was building for them, every new mfgr promising better performance, none delivering.
 
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Anthony said:
I looked into this a while ago, and since we do not have natural gas to our neighborhood quickly dismissed the idea. I think it is a good solution however, especially if you use a lot of hot water.
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Ours runs on propane and a tankful runs a good long time (the only thing we use it for is domestic hot water, the cooktop, the bbq, and the backup generator).
 
When I was growing up, I lived in the Netherlands for a year. They had a small tankless heater at every tap. It worked REALLY well - And no more running-two-supply-lines-to-every-faucet-in-the-house - One water supply line, split at the faucet with half going to the heater. And not only was the hot water endless, it was also instantaneous and there was no heat loss in the pipes.

I really wish it was possible to do that here - Even with tankless we still use a central water heater and have some heat loss in the pipes as well as using a bunch of water in the process of getting the hot water from point A (heater) to point B (faucet). And whoever built my house seems to have managed to put the water heater in a spot where hot water doesn't get to ANY of the faucets quickly... Even the one that's almost directly above it.
 
Tankless water heaters have their benefits..

Gas fired ones are better.. For those who want to go the electric route... Keep in mind you will need a HUGE service leading to them... Last customer wanted one and it needed 100 amps..... So... 3 leads of 1/0 THHN, 1 #2 ground and a 100 Square D double pole breaker later, it worked.. But the power meter spun so fast while the unit was running you needed a strobe light to see it..:hairraise::hairraise:..

To put it in perspective... His heater used more power then my TIG welder, DC225 Lincoln welder, Milling machine and Plasma cutter all running at once...

Take away message.... Electric tankless heater = DEAD short..;) YMMV.
 
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