Tankless waterheaters??????

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Chance9768

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Has anyone made the switch to a tankless watterheater? Are they all that they are cracked up to be? With three kids and a ton of cloths being washed our 40 gal. tank is just not enough, been thinking about eather going with a 50 gal or going tankless. Any feedback yall?
 
i've wired for several electric on demand water heaters, they are very nice. they take a lot of juice so make sure you've got about 90 amps free in ur electrical service, or room for a subpanel somewhere. with the fluctuating prices of natural gas, i'd go the electric route, but it kinda depends on what your original tank is plumbd for... if it's gas, stick with gas. if u got the xtra money for tankless, it's very well worth it, and the xtra 10 gallons u get from the 50 really isn't gonna make too much of a difference i wouldn't think. plus you'll free up some good storage space and use the spot from ur old heater for beer ;)
those lil remote thermostats are nice too.. u can install it right next to your AC/HEAT thermostat (if convenience of installation allows)
 
main things youll want to be sure of is enough electric and gas and water supply. ive gone into several homes where piping was too small going into or out of the unit which can cause it to turn itself off. highly recomend tankless over tank. well worth the bit of extra cash it will cost. though there are a few units that cost just around the price of a standard tank water heater. good luck with what ever choice you make.
 
Here in germany, all of my hot water comes for an 'instant on' tank-less water heater. Mine is gas powered and it does not take very long to get hot water to the shower, Heater in the basement, shower on 2nd floor(right over the heater) and i have great hot water in under 20 seconds. I love it. It does not cost all that much to run, my heating bill (house/floor/water all gas heated) only runs ~75 euros a month.
 
The tankless heaters are rated by temp rise at a certain GPM. IMHO (I'm not a plumber) to beat a 40 gallon tanked heater, you're going to spend over $1000 and require at least a 3/4" gas supply.

What is the temperature of your hot water output right now? If you have the thermostat set to something like 120F or lower you're going to run out fast. I run mine at 145F and we can take 2 showers at a time and 2 more back to back. Hotter water in the tank means less in the mix so it lasts longer. The downside is that your kids need to understand not to turn only the hot water on because it's a bit hot. My daughter is 4 and she knows to turn on the cold first, then add a little hot.
 
Which kind are you considering, on-demand or single whole house tankless? I got the single whole house tankless unit to replace my old tank unit. I still have to wait for the hot water but once it's hot it never runs out. I liked the fact I wasn't heating water in a tank all the time. It's only on when you want hot water.
 
I've got a whole-house propane tankless water heater. Love it. Hands-down some of the best money I spent on the new house a couple years ago.
 
The tankless heaters are rated by temp rise at a certain GPM. IMHO (I'm not a plumber) to beat a 40 gallon tanked heater, you're going to spend over $1000 and require at least a 3/4" gas supply.

My water heater recently sprung a leak, and I looked very hard into replacing it with a tankless model. It didn't take long to find out that my gas supply was inadequate, and also discovered that I'd need to replace the vent pipe with a larger, stainless steel one. (I'm not sure why stainless is required, but that's the code.) I really wanted to DIY the job, but the necessary upgrades knocked it out of that realm.

I ended up swapping in a conventional heater, 10 gallons larger than the old, for about half the price of the tankless. And that's without including the price of the gas/vent upgrades. Took me about four hours, start to finish.

FWIW, my parents recently remodeled and installed an electric tankless heater for their new master bath. They're not real happy with it, and say it's extremely hard to adjust for a stable temp in the shower.
 
I've got the big natural gas tankless whole house unit. It is rated to run at least 2 showers. It does that even with our winter ground water temps around 50F. I can fill a regular bath tub hot water full on.

I think they are great units. They last much longer than tanks, take up much less space, use less energy and you never run out of hot water.

Just a couple of downsides.
First we have a large whirlpool tub with an extra large tap. Full on exceeds the capacity of the heater and the water coming out is cool. However previously with a tank the tank was empty before the tub was full so that was not a good solution either. Instead we just fill the tub with the valve only partial open.

Second you can't dribble the hot water like you might when washing dishes. The tank shuts off when the volume drops below a certain amount. It basically requires the valve on a sink be half open to operate.

Third if you do a dumb thing like leave the hot water running while you leave the house it will keep the water running hot the entire time, spending much more in gas costs that a regular tank.
The city had shut the water off to the house for some water main repairs one day. When my wife couldn't get hot water for a shower, she left the valve open instead of shutting it off. We left for the day and came back hours later to a hot steamy shower still running.

to Mike Flynn: The unit we have would heat your water up enough for a shower even with 38F input. However you wouldn't be able to run two showers like we can down here in temperate climates. :)


Craig
 
My parents have one and they have the same problem with trying to trickle hot water. That's what happens in the summer when the ground water is 85F and want to take a shower. The hot water requirement is so low at that point that the burner shuts off. They have to run the sink hot water valve at about 1/4 open while they're taking a shower. So much for saving. They have to waste water and energy in the process.
 
Any unit i get will be electric. Geting enough power to the unit will not be a problem. I'v thought about turning up our heater that we have but we allways have little kids around the house and I would hate fore someones kid to get burn there hands. Even with the temp turned up I dont think it would help with the dishwasher going and washing cloths in hot water. There are some mornings that its not uncomon for there to be 5 or 6 showers taking in a row.(and cant forget about the teenage daughter who camps out in the shower, some times I have to close the hot water valve off just to get here to stop taking a shower.) Is there anyone who has swaped over to a tankless? I was wondering if there elect. bill has gone up or down. at $450 it would be nice to save a little bit.
 
When we bought our house , the first thing to go was the bathroom followed by the 40 gal electric water heater. The SWMBO "Needed" a 60 gallon jacuzzi "bathtub/whirlpool " A Takagi tankless water heater was a necessity at that point, also freed up an entire closet, and when you've got only a 1,000 sq foot house every closet counts. And since we were redoing all the wiring , gas & plumbing anyway it wasn't that big of a deal to install.
Never having to take a cold 2nd shower is priceless. Think about it: 40 gal hot water heater + wife washing & conditioning hair , shaving and all that crap - 30 min MINIMUM and a 1-2 gpm shower head = Cold shower for you
I'd never go back to a tank type heater

Jens
 
Anyone know what the amp draw on these units is? I'm kinda wondering what would happen if I were welding while it was running and the well pump kicked on, all at the same time (on a 200 Amp service).

It sounds like they operate pretty well under consistent flow, which would make one perfect for the radiant heating in my garage. I'd love not to have to give up a corner of my basement to another water heater and I'd probably only need a small reservoir instead of 30-40 gallons.
 
I've built homes with both Rinnai and Noritz tankless LP Gas (propane) water heaters. They're both great and worth every penny. My own house has a Rinnai and I love it. I think it takes a few extra seconds to get hot water than a tank, but it's no big deal and is more than made up for in the cost savings, especially if you're on a well and water cost is nominal.

Last I checked (couple years), they don't make an electric tankless water heater that can handle heating water for a whole house (realistically). You'd only have enough energy to heat water enough for one, maybe 1.5, fixture(s) at a time. So, for example, you couldn't take a shower while running the dishwasher or washer machine. The best you could do for electric is have multiple heaters for different parts of the house, which could get sort of ridiculous.

Gas tankless water heaters are the only viable option. One of the somewhat unforseen costs is venting the water heater. If you can mount it near an exterior wall, venting isn't a big deal. The manufacturers will only allow so many feet/elbows of vent pipe and the more the plumber/gas tech. has to run, the more it will cost.
 
I am in the Plumbing Wholesale business and am asked this question almost every day. Things to consider; gas/electrical requirements, venting, indoor or outdoor. I know many have already responded with good info but I wanted to chime in on something I actually know something about.:mug:

You need a minimum 3/4" dedicated gas line. Most require 4" ss vent pipe, although some use a concentric vent pipe which minimizes your clearence from combustables. Stainless is required because of the exhaust heat.

I live in southern california where a 50 gallon heater cost about $500 plus install and a tankless runs a bit shy of $900 plus install. If you can do an exterior heater you will save a lot of money on vent pipe.

I hope this helps.

Cheers
:mug:
 
I think they're great, at least the NG and propane ones. It's worth the extra money to get one where you can set the output temperature. Look for one designed to operate with solar, they can take just about any input temperature and still give you a constant output.
 
Any unit i get will be electric. Geting enough power to the unit will not be a problem. I'v thought about turning up our heater that we have but we allways have little kids around the house and I would hate fore someones kid to get burn there hands. Even with the temp turned up I dont think it would help with the dishwasher going and washing cloths in hot water. There are some mornings that its not uncomon for there to be 5 or 6 showers taking in a row.(and cant forget about the teenage daughter who camps out in the shower, some times I have to close the hot water valve off just to get here to stop taking a shower.) Is there anyone who has swaped over to a tankless? I was wondering if there elect. bill has gone up or down. at $450 it would be nice to save a little bit.

Not really going to work for you. First to get the kind of temperate and volume you need for multiple fixtures you will need multiple units. I havn't seen a single electric unit with enough power. Thats going to cost big bucks in the units and upgraded service. Plus you won't save much money. Electric water heaters with extra insulation are extremely efficient, gas water heaters lose alot of heat through the exhaust pipe. The heating elements are very similar so no real savings. The only advantage in your case is the space savings. Just get a bigger tank and/or replace the shower heads with ultra low flow ones.

Craig
 
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