Randy in Maine
Well-known member
I will never go back to a tank water heater. I can run my little Baxi whole house boiler/water heater using my camping battery even when the power goes out. Takes up almost no space and very cost effective heat.
Tankless Water heaters, yeah or nah?
- Thread starter joseywales
- Start date
Spiritwalker2222
Member
I have a tankless water heater. It's a big waste of money. A $3700 heater that replaces a $600 tank. To save $10 a month in natural gas, but waste $15 in water cause I have to run the water so much longer for it to heat up.
Just wait until it breaks and those regular maintenance cleanings.......then your really going to be unhappy
My electric tankless also takes for ever to get hot water to the distance faucets.
what heater did you pay $3700 for? a 199k 96% Rinnai (my opinion - the top of the line) is $1800 delivered.
Just wait until it breaks and those regular maintenance cleanings.......then your really going to be unhappy
My electric tankless also takes for ever to get hot water to the distance faucets.
how's that work? the issue there is pipe length, not the heater. I have a tank, and a single line that snakes around the whole house. takes a real 4 minutes to get hot water upstairs just running the sink. it's not the fault of the waterheater.
Depends on how your determine the fault as poor design or poor performance or poor install or limitations of tankless or combination of all the above.
My regular home with the NAT gas tank has a gravity return system which has instant hot water at every faucet ( 60’ long ranch 4 bath) and as stated prior my hot water costs are $8 per month.
The electric tankless is a pipe problem and location issue To solve purchasing multiple tankless and wiring costs is not cost effective. This a vacation condo on the top floor of a 5 floor unit. Running 220v 3 50 amp circuits across the condo is out of the question. The current unit is with in two feet of the service entrance and water meter. Positive this was done for cost. This is a three bath unit even the close bath has a considerable wait for hot water and the distant bath is measured in minutes. Multiple units is not an option. Tank unit in a vacation condo is not a real choice since condo space. Tankless works good enough in this situation and we live wit(the delay. If it was full time Home knowing what know now I would have done a different layout. Even the delay to the wash machine and dishwasher causes issues.
The condo building itself is 100% electric no propane no NAT gas.
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My Old Tools
Well-known member
I have a couple of tankless, and both are recirculators that provide instant hot water at all locations. Mine are Navien. Cost about $1100.
200mph
Member
Yea, tankless all the way.
Our prior home (5BR 6 BA) had two 50 gallon conventional units, and the electric bill was through the roof.
We now have a Rinnai tankless, it runs on propane, and the overall energy savings are very significant. So much so, I'm looking to pull the 30 gallon electric water heater out of the workshop and replace with an electric tankless, likely a Rheem.
No point in keeping that big pot of water hot when its only going to be used occasionally.
Our prior home (5BR 6 BA) had two 50 gallon conventional units, and the electric bill was through the roof.
We now have a Rinnai tankless, it runs on propane, and the overall energy savings are very significant. So much so, I'm looking to pull the 30 gallon electric water heater out of the workshop and replace with an electric tankless, likely a Rheem.
No point in keeping that big pot of water hot when its only going to be used occasionally.
How much do you think it costs per year to keep 30 gallons of water hot in a modern well-insulated tank water heater?
Hpozzuoli
Well-known member
I have a Rheem and I think it’s the same one that TTA89 has. I think it’s one of the better rated units. It has performed great. Takes a minute for the hot water to come, but once it does, it doesn’t stop. Intstall was simple and straightforward. I don’t pay attention to energy efficiency. I pay attention to life efficiency and unlimited hot water helps the cause. I couldn’t see how it couldn’t be cheaper than storing 60gallons of water around the clock.
about 40% of the bill - so if you use $9 a month for gas, that's not much. multiply that by a city of 60k people, and all of the sudden it's near a quarter mil/year.
per .gov:
https://www.nrel.gov/docs/fy15osti/63880.pdf
The average gas storage heater is <60% efficient - so 40% of the fuel burned doesn't contribute to providing hot water.
How much does it cost ?.........Almost 100 posts the topic time to revisit the math again:
If you save $4.00 per month. 40% of the $10 gas bill.
Tankless install is $2000 it takes 500 months to break even or 41 years.
If the install is simple with no gas line and meter upgrades and you get by for $1000 up charge then the payback is 250 months 20.8 years.
There are posts where the tankless install are $2500 to $3500.
Then there is the pesky maintenance issues.
If you save $4.00 per month. 40% of the $10 gas bill.
Tankless install is $2000 it takes 500 months to break even or 41 years.
If the install is simple with no gas line and meter upgrades and you get by for $1000 up charge then the payback is 250 months 20.8 years.
There are posts where the tankless install are $2500 to $3500.
Then there is the pesky maintenance issues.
ripperd
Well-known member
Install one of these guys, and set your water heater up near its max temp. Problem solved! I did this when I installed a whirlpool tub. Worked perfect, and as a side benefit, the hot water was a perfectly consistent temp. No more temperature variation based on when the water heater last cycled (stacking effect).
https://www.homedepot.com/p/Cash-Ac...PIPHorizontal2_rr-_-203721329-_-206945096-_-N
sleek98
Well-known member
Never seen that before, but I like it. Going to order one and see if it lets me fill the tub up.
TheEquineFencer
Well-known member
I'll put my $0.02 worth in...I considered a tankless...I spoke with the people at a Greenville Utilities in their energy conservation section. It went something like this...about a 50 gallon heater would cost less than $5-$10 a month to just sit and maintain, a Tankless $0, when the usage goes into play, the 50 gallon tank heater only has (2) 2500-3500W elements that come on, only one at the time. and might be on for maybe an hour to recover. The tankless pulls 50KW the entire time. He told me with electric it was crazy. With LPG or NG it was close to even....unless you have kids...they'll run the water bill out of sight and gas usage goes up the same. If you had a large complex like condos and such with intermittent high usage, Tankless made sense. He told me he's personally been out and checked sites after people went from both Electric to tankless and also from LPG and NG to tankless to investigate the reason for their high water and gas usage. Some switched back after looking at the increased usage of water and gas. A long hot shower with endless water sounds nice...until it's time to pay the bill. Conservation is key.
I don't think you would be saving $10/month, the minimum you can pay is about $18-19 for Centerpoint. My bill for last month was $21.26, $16.45 of that was the standard fee and approximately $3 was for actual gas usage (5 CCF), with the rest taxes.
All that said, I still want to do tankless simply to get the water heater out of the laundry room and free up the space.
Haha I don't think he was using gas to run his electric hot water tanks. Those electric units pass on something like 99.x% of their energy to the hot water and typically have a UEF of between 92% (super cheap tank) and 95%. That means that you're losing between 7% and 4% of the energy to standby loss. That's not much at all.
With a traditional gas tank you do have a flu up the middle. I think that is what hurts standby efficiency. Step out of traditional to this:
20 gallon gas water tank heater with modulating 50k/100k BTU burner. Burner is up to 95% efficient and UEF is .87. A small well-insulated tank keeps the standby losses down and the 50/100k BTU heat exchanger can run a shower forever (and multiple showers for a while) and it needs no annual descaling maintenance. You get the best of both worlds: immediate low flow hot water, no annual maintenance, very competitive efficiency, cheap fuel source, less complexity than a tankless, can run a hot shower indefinitely (and multiple showers for quite a while), compact size, stainless steel tank and heat exchanger, and 20 gallons of hot water if the power goes out. It also comes with a pre-installed mixing valve so you can keep the 20 gallons at up to 167*F and still have an output temp set to your liking (usually 120-140*F.)
http://westinghousewaterheating.com/residential-gas-floor-hybrid.html
Seriously. We need to see more companies making these. This Westinghouse is a rebranded HTP unit. I have one sitting in my garage right now. I can't wait to put it in!
That was an interesting read. If only the people that built homes/buildings cared about this stuff.
With a traditional gas tank you do have a flu up the middle. I think that is what hurts standby efficiency. Step out of traditional to this:
20 gallon gas water tank heater with modulating 50k/100k BTU burner. Burner is up to 95% efficient and UEF is .87. A small well-insulated tank keeps the standby losses down and the 50/100k BTU heat exchanger can run a shower forever (and multiple showers for a while) and it needs no annual descaling maintenance. You get the best of both worlds: immediate low flow hot water, no annual maintenance, very competitive efficiency, cheap fuel source, less complexity than a tankless, can run a hot shower indefinitely (and multiple showers for quite a while), compact size, stainless steel tank and heat exchanger, and 20 gallons of hot water if the power goes out. It also comes with a pre-installed mixing valve so you can keep the 20 gallons at up to 167*F and still have an output temp set to your liking (usually 120-140*F.)
http://westinghousewaterheating.com/residential-gas-floor-hybrid.html
Seriously. We need to see more companies making these. This Westinghouse is a rebranded HTP unit. I have one sitting in my garage right now. I can't wait to put it in!
That was an interesting read. If only the people that built homes/buildings cared about this stuff.
like2wheel
Well-known member
Haha I don't think he was using gas to run his electric hot water tanks. Those electric units pass on something like 99.x% of their energy to the hot water and typically have a UEF of between 92% (super cheap tank) and 95%. That means that you're losing between 7% and 4% of the energy to standby loss. That's not much at all.
With a traditional gas tank you do have a flu up the middle. I think that is what hurts standby efficiency. Step out of traditional to this:
20 gallon gas water tank heater with modulating 50k/100k BTU burner. Burner is up to 95% efficient and UEF is .87. A small well-insulated tank keeps the standby losses down and the 50/100k BTU heat exchanger can run a shower forever (and multiple showers for a while) and it needs no annual descaling maintenance. You get the best of both worlds: immediate low flow hot water, no annual maintenance, very competitive efficiency, cheap fuel source, less complexity than a tankless, can run a hot shower indefinitely (and multiple showers for quite a while), compact size, stainless steel tank and heat exchanger, and 20 gallons of hot water if the power goes out. It also comes with a pre-installed mixing valve so you can keep the 20 gallons at up to 167*F and still have an output temp set to your liking (usually 120-140*F.)
http://westinghousewaterheating.com/residential-gas-floor-hybrid.html
Seriously. We need to see more companies making these. This Westinghouse is a rebranded HTP unit. I have one sitting in my garage right now. I can't wait to put it in!
That was an interesting read. If only the people that built homes/buildings cared about this stuff.
That's a very interesting product.
Thanks for posting
There are commercial tank heaters that have flue dampers - they close when not in use. probably buys a point or two of efficiency. I doubt they'd put them on if they accomplished nothing.
tankless water heater: $2000
being able to fill your 80 gallon tub with hot water: priceless
new tank water heater: $500
tankless water heater: $2000
being able to fill your 80 gallon tub with hot water: priceless
mixing valves are a great idea for any water heater - even if you don't tweak the heater super hot. keeps kids from getting burned.
Now that we have concluded filling the tub is priceless ...........and some purchase decisions are not related to price or payback ............irrational purchases should be more fun than a tankless heater like:
Buying $125k RV to ............save money on hotels
Buying a $30k motorcycle to .............save money on gas.
Buying $50k bass boat to...........................save money on fish at Sam’s club
Saving the planet by buying a Tesla for $60k.............telling the wife we are going to save so much on gasoline..........when we really just wanted a new coolest car on the market and becoming a member of the Tesla club.
Buying $125k RV to ............save money on hotels
Buying a $30k motorcycle to .............save money on gas.
Buying $50k bass boat to...........................save money on fish at Sam’s club
Saving the planet by buying a Tesla for $60k.............telling the wife we are going to save so much on gasoline..........when we really just wanted a new coolest car on the market and becoming a member of the Tesla club.
TheEquineFencer
Well-known member
I'll stick with my '92 Geo to save on gas...for a while...until the price of the Tesla's come down...
Streetbu
Well-known member
Wow, not sure where you guys buy your water heaters but you're getting screwed. I bought a Bosch on demand propane water heater. Smaller one, we only have one bathroom. Between plumbing fittings, moving the propane line, exhaust pipe, and the heater I had 1k into it total. I consider my labor free. Unfortunately my basement is horrible, walls leak, so it's often wet, and always damp. Plus well water with a higher level of minerals, and at the time I didn't know the above. But for the 9 years I had it it saved me quite a bit on my propane bill. I recently switched back to a standard 40 gallon style tank, tankless had issues with mineral buildup, and my propane usage has gone way up. Only reason I went back was because we're tearing the house down next year and rebuilding. Didn't want to invest in a tankless that would get ruined in a short time until we rebuild.
^^^^^^^^^^^ 4 or 5 bedroom 4000 sqft home might have a 200,000 btu tankless 11gpm. So one size does not fit all needs. So $1500 for the unit and “simple install” might be $1500. Add new larger gas line and meter etc can double the install price.
GJ is often all about DIY. That’s why many of us are here. The toilet flapper topic and getting plumber seems to indicate a few GJ guys are not doing DIY. ( likely a minority on simple stuff).
On a major install..........
Water heaters in general have been a topic on the DIY topic prior on do you get permit ? Do you do your gas line install ? Do you solder ? Do you do own electrical work ?
Tankless do you get permit ?
Tankless do you DIY and how does that effect warranty service and parts ?
Do all tankless manufacturers sell to the public ? Do the sell parts to the public ?
DIY HVAC was be a hot topic prior and tankless have many of the same install issues.
GJ is often all about DIY. That’s why many of us are here. The toilet flapper topic and getting plumber seems to indicate a few GJ guys are not doing DIY. ( likely a minority on simple stuff).
On a major install..........
Water heaters in general have been a topic on the DIY topic prior on do you get permit ? Do you do your gas line install ? Do you solder ? Do you do own electrical work ?
Tankless do you get permit ?
Tankless do you DIY and how does that effect warranty service and parts ?
Do all tankless manufacturers sell to the public ? Do the sell parts to the public ?
DIY HVAC was be a hot topic prior and tankless have many of the same install issues.
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ManOnTheCouch
Well-known member
- Joined
- Apr 23, 2018
- Messages
- 130
We love our tankless LP water heater - particularly with 3 teenagers and a wife that likes hot baths. We would never go back to a tank. Zero maintenance issues either. From a cost and efficiency standpoint, it ends up being enough of a wash either way that the lifestyle choice should drive the decision. We can have three people shower at the same time indefinitely still have unlimited hot water.
OP
joseywales
Well-known member
The heater is what, 20" round I guess. So stand that up in the middle of a wall. Now what can you do with the rest of the wall, in a finished basement? "Box" it in? Our plan was build a large, 2 foot deep closet for storage on one side. and maybe a closet on the other. Instead, I retained a finished space that's nearly 3 feet deep and almost 15 feet long.
6768rogues
Banned
In my primary residence in NY, I have a tank type water heater. I don't want to buy something as expensive as a tankless because then I am married to it and cannot waste money by throwing it away if it breaks. At our place in FL, we have a tankless because the house came with it. There they just hang the water heater on the outside of the house, so we don't have a convenient place to put a tank type. Last year it gave out and it cost dearly to have it replaced.
Milton Shaw
Well-known member
- Joined
- Feb 11, 2011
- Messages
- 4,844
I have a small electric tankless in my shop for the utility sink. Hot water is about 10 seconds from time you turn it on. One thing I have noticed is that if you run it, turn it off and run water again in just a few minutes. Because of heat soak that first water the second time will scald you. You have to run enough water for it to turn back on before you can depend on the water not to burn you. This is a problem with intermittent use of hot water like you would do washing and rinsing dishes for instance. I have a 30 gallon fast recovery gas water heater and it supplies plenty for us even when we have company.. Low flow shower heads just about throttle the water flow down until the water heater can keep up with the shower.
olytdi
Well-known member
I installed a Bosch tankless in about 2003 or 2004. I had the gas lines increased from 3/4" to 1-1/4" (my neighbor was a pipe fitter). It has worked flawlessly for the last 15 years without a single problem. I put a valve rebuild kit in once about 6 years ago.
Yes, it provides hot water when there is no power (provided you're on city water which is likely if you have natural gas).
I concur that it is a tad annoying that the water has to run a while to get hot to the faucet if it's at all a distance from the heater.
My gas bill dropped 60% when I installed it. Never made sense to me to heat 50 gallons of water 24 hours/day when I use it for less than 20 minutes a day...
Yes, it provides hot water when there is no power (provided you're on city water which is likely if you have natural gas).
I concur that it is a tad annoying that the water has to run a while to get hot to the faucet if it's at all a distance from the heater.
My gas bill dropped 60% when I installed it. Never made sense to me to heat 50 gallons of water 24 hours/day when I use it for less than 20 minutes a day...
TTA89
Well-known member
We've been more than happy with our LP Rheem tankless in our house. We have a 2 bed, 1 1/2 bath Townhouse that we rent out. The 40 gallon water heater just gave up and we are going to try this one, it's electric. There is no gas in the townhouse complex.
https://www.amazon.com/gp/product/B003N3NRY2/?tag=atomicindus08-20
https://www.amazon.com/gp/product/B003N3NRY2/?tag=atomicindus08-20
I have a Bosch Aquastar 125B that does not reduce volume. So do all of the new tankless reduce volume to meet temp or do only certain ones?
what do you mean by does not reduce volume?
volume is determined by how far you have the hot water valve at the faucet open, not the water heater. if the water heater can keep up with the BTU requirement of a given flow, then you get water at the setpoint. if not, it's colder.
if it didn't reduce the volume of gas being burned to match, it would eventually boil water and explode (or pop the T&P valve).
ripperd
Well-known member
He is meaning the opposite - IE when the demand for hot water surpasses the BTU capacity, it will restrict and slow down the flow of water so that it leaves the heater at the setpoint. Basically if you had that, combined with temperature compensating shower valves, you could run more appliances/showers, and the temperature wouldn't drop, the flow would just reduce.
Plumbermike
Member
Hey guys I'm a hot water specialist, I don't like tankless units, more things to go wrong ,parts if not stocked , have no hot water tell parts arrive.. water quality is a factor , most tankless manifcturers require water filter, for warranty . Deliming the units periodically. Have to wait for hot water,units are often relocated to different location,reason for waiting.. people are thinking they are the greatest.
If you don't need the current space where w\h is located, keep the tank type W\h I prefer them. But it's your choice your home..
That's what I have to say about that..
If you don't need the current space where w\h is located, keep the tank type W\h I prefer them. But it's your choice your home..
That's what I have to say about that..
Plumbermike
Member
Your suppose to get water heaters ,water softners,dish washers other appliances permitted depending on the state you live in.. what that does , properly installed, unit is up to current building codes, here in California. Water heaters inside the home must have drain pan,drain line must run to exterior (if possible) same with t&p ,a coated gas flex is required, working isolation valve,eq straps, expansion tank installed on cold supply, sediment trap installed on gas inlet to water heater. 3 screws per vent connection,bonding hot cold and gas lines, insullating hot and cold lines.. in garage must be on platform 18"min, if installed on drywall must have drain pan ,line run outside.. pulling permits brings your older home up to current building codes,. Get this guys, I had new heater with AC installed, pulled permits, upgraded elec main ,the county increased property tax 1000 bucks a year.
i wonder how that would work in practice.
what do you recommend for a high efficiency, sealed combustion water heater?
I don't know of any tankless unit that will modulate the water going through them -- automatically. What they do is modulate the BTU's going to that water.
In a cold climate the water going to the unit obviously is going to need more BUT's to bring up to a stable shower temp. The problem with the older units was they had a static rise -- the unit was on or off. Just like the new mini splits -- the better units match the BTUs to the water flowing through the unit.
The thing that must be matched -- flow needed throughout the house. Many of the units have minimum flow requirements that require the faucet to be opened all the way -- and the unit must be able to modulate down to run continuously when only one faucet is open ..or you get water fluctuation temps. That's why many have mixing valves to help them. On the other side -- you must have a unit that is large enough to supply all of the hot water that would be required at a given flow and rise.
The above is why you see more than one unit in many houses -- it's difficult to get to be able to do both in a large house. When you are only doing a single bathroom or even a single shower as I have at the beach -- it's easy to size and the units are very close to the outlet.
since they can not store the hot water -- you have to wait for the unit to start -- heat up and for that hot water to reach the outlet. Now some unit have small tanks and even recirculation -- sort of a hybrid.
In a cold climate the water going to the unit obviously is going to need more BUT's to bring up to a stable shower temp. The problem with the older units was they had a static rise -- the unit was on or off. Just like the new mini splits -- the better units match the BTUs to the water flowing through the unit.
The thing that must be matched -- flow needed throughout the house. Many of the units have minimum flow requirements that require the faucet to be opened all the way -- and the unit must be able to modulate down to run continuously when only one faucet is open ..or you get water fluctuation temps. That's why many have mixing valves to help them. On the other side -- you must have a unit that is large enough to supply all of the hot water that would be required at a given flow and rise.
The above is why you see more than one unit in many houses -- it's difficult to get to be able to do both in a large house. When you are only doing a single bathroom or even a single shower as I have at the beach -- it's easy to size and the units are very close to the outlet.
since they can not store the hot water -- you have to wait for the unit to start -- heat up and for that hot water to reach the outlet. Now some unit have small tanks and even recirculation -- sort of a hybrid.
I didn't know some tankless were only on or off. My old one regulates BTU based on water volume so I adjust it every fall and spring. Also, you need at least 1/2 gal/minute to activate on low flame.
I thought the new ones had electronic sensors and based BTU on temperature.
I thought the new ones had electronic sensors and based BTU on temperature.
That's how they worked .. they did not have modulating gas valves. There still is a min flow problem with some units. Stuff gets better ...
The one for my outdoor shower at the beach is perfect -- it's the smallest one I could get and with the set flow it's almost all hot for most people taking a shower. Simple on/off .. and it's about 4' from the shower on the wall of the garage. I drain it for the winter ... obviously never has really cold water going to it.
"I don't like tankless" Well, it is your business but you are in the hottest tankless market in America, so...? "To many things to go wrong..." I would suggest you contact Keyline Sales (Downey, 562 904-3910) for training on tankless. Water filter required? No, a water filter is built into the cold water inlet. If you have a lot of **** in the water supply I think it is sensible to have a filter. Don't you? I pulled the inlet filter on my unit for the first time after 4 yrs. Clean as a whistle. De-liming? I had one tankless in my home for 13 years and never touched it. It depends upon your water quality. If you have junk water your tank water heater will have the same thing happening. You just don't see it. "have to wait for hot water/Location?" You have to wait for hot water regardless of source. In some situations re-locating the new tankless is precisely what should be done to better provide comfort to the homeowner. I always look at the job and bid it where the existing system is. That is position "1". I will then look at the building lay-out in relation to the tank location. If I find a better position "2", to provide better comfort and economy to the homeowner I will quote it there. It is then a matter of features, benefits & cost as to the customers decision of 1 vs 2. I term this as not perpetuating the mistakes of the original low cost bidder. In CA everyone puts the water heater in the garage. That may be a million miles from the M BR or Kitchen. Tankless unlike tanks do not require expansion tanks. Your inspector may require it, but it is not necessary.
I've been using tankless for the last 20 yrs with nary a problem. Installed correctly, in the few tens of thousand units I've been responsible for they are excellent. Installed by someone who isn't properly trained, you have exposure. If you are having a tankless installed confirm the dealers factory training and ensure that the guy doing the work has been trained as well. If you are installing one yourself, read the damned manual and follow it. I am a hot water specialist and will have nothing but a tankless!
Oh, and btw, The National Fuel Gas Code's 2012 edition removed the requirement to elevate a tank water heater 18". In the mid-'00's the tank guys had to add the Flame Vapor Recovery equipment to keep from blowing up peoples houses. As they are sealed systems there is no longer a requirement for the elevation.
rjn2649
Well-known member
Didn't read through this all, but I will add. We have an older Bosch tank less, she had it before I meet her, and it was more installed as a space saver, than an energy saver. I come along and fix some old leaky faucets and such...suddenly NO hot water, WTF? Turns out some of these things don't like lo flow fixtures, so when it's time to upgrade/change fixtures I always got to check the flow rates