Tankless hot water heaters?
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I have one and like it a lot. Mine is a propane model and will supply enough hot water for 2 showers at the same time. It is nice when all four of us can take showers and not run out of hot water. One thing I didn't account for when choosing a tankless one was that we use more water now because we take longer showers. :|
Some things to keep in mind when replacing a tank model with a tankless is that the tankless one will need more electricity/gas than the tank model so you will most likely need to run new wiring or gas pipes to it. I think some people who replace their tank model with a tankless don't supply it with enough amps or BTU's and then complain that it doesn't perform like it should.
Some things to keep in mind when replacing a tank model with a tankless is that the tankless one will need more electricity/gas than the tank model so you will most likely need to run new wiring or gas pipes to it. I think some people who replace their tank model with a tankless don't supply it with enough amps or BTU's and then complain that it doesn't perform like it should.
Tekno_Cowboy
Flashlight Enthusiast
While tankless may use more gas/electricity while in use, it should use less overall, due to the fact it's not keeping the water hot all day.
When replacing a water heater, one of the primary decisions should be the fuel type, electricity or gas (lp or natural gas.)
Generally, it is more costly to produce hot water with an electric water heater than a gas (lp or natural gas) water heater. The cost difference can be so dramatic as to overcome the cost of retro-fitting a total electric house (remember those from the 70's) with gas.
Tankless Water Heaters seem to follow the same fuel effiency as the tank type. The savings are, as Techno Cowboy has stated, in that the hot water is produced only upon demand.
Generally, it is more costly to produce hot water with an electric water heater than a gas (lp or natural gas) water heater. The cost difference can be so dramatic as to overcome the cost of retro-fitting a total electric house (remember those from the 70's) with gas.
Tankless Water Heaters seem to follow the same fuel effiency as the tank type. The savings are, as Techno Cowboy has stated, in that the hot water is produced only upon demand.
They will both use less gas or electricity overall because they use the fuel more efficiently but the immediate and rapid heating of the water takes a higher volume supply line to the unit ie: larger gas line or larger electrical conductors.
I've been in two houses now a total of 5 years on tankless fed by natural gas. As others said, be sure to calculate up how many gallons per minute of hot water you want to use at the same time ie: two showers @ 2.5 gallons per minute each, kitchen faucet for washing dishes - 1.5 gallons per minute, 1 bathroom faucet at 1 gallon per minute etc. etc. This is the absolute minimum size (GPM or gallons per minute capacity) you will want to buy. This is not to be confused with how many POTENTIAL uses you COULD have on at the same time. Only the worst case scenario - what could I be using at the same time. Many plumbers will quote a small unit to keep the costs down but you will not be happy. If you don't do this and buy one with too small a capacity, you will end up getting luke warm or cool water if all of the calculated uses are in use at the same time. I believe mine have been in the order of 6 gallons per minute but there are only two of us in the house.
I've been in two houses now a total of 5 years on tankless fed by natural gas. As others said, be sure to calculate up how many gallons per minute of hot water you want to use at the same time ie: two showers @ 2.5 gallons per minute each, kitchen faucet for washing dishes - 1.5 gallons per minute, 1 bathroom faucet at 1 gallon per minute etc. etc. This is the absolute minimum size (GPM or gallons per minute capacity) you will want to buy. This is not to be confused with how many POTENTIAL uses you COULD have on at the same time. Only the worst case scenario - what could I be using at the same time. Many plumbers will quote a small unit to keep the costs down but you will not be happy. If you don't do this and buy one with too small a capacity, you will end up getting luke warm or cool water if all of the calculated uses are in use at the same time. I believe mine have been in the order of 6 gallons per minute but there are only two of us in the house.
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Launch Mini
Flashlight Enthusiast
Have one at the cabin, works great.
I think in the home it would work better, as our water source always has varying water temps. So one day you get a perfect shower, then if the temp goes up, you get a smoking hot shower.
BUT overall ,really like it.
I think in the home it would work better, as our water source always has varying water temps. So one day you get a perfect shower, then if the temp goes up, you get a smoking hot shower.
BUT overall ,really like it.
Sgt. LED
Flashaholic
Thought about getting one but due to the larger up-front cost of the unit and proper mounting uncertainty I said screw it and went for another tank. I KNOW how to properly install a tank!
Our old one was so crazy old the new one is saving us money and cost way less than an on demand system. Win - win.
I have no clue how long the on demand systems last either. :shrug:
Our old one was so crazy old the new one is saving us money and cost way less than an on demand system. Win - win.
I have no clue how long the on demand systems last either. :shrug:
gt40
Enlightened
I have had a takagi for 7 years and it works great. You do need to descale the valve once a year if your water is hard. You put some descaling agent in and let it sit off for a bit and then flush it. The other thing is placement matters. If you have a large house or 2 story, consider getting a second one for faster hot water or recirculation pump. Good luck with it but they are definitely the way to go...
ironhorse
Enlightened
We had one before moving. It was an electric one. It worked okay most of the time for showers and doing dishes, but it wouldn't make enough hot water to have the faucet on very fast to fill the bathtub.
Appreciate the input. Spent the better part of today surfing and making calls. From what I gathered I was in the 6-7 GPM range with the extra headroom allowed. There are 3 of us but seldom do we overlap in taking showers or using other water appliances. The tankless would allow that though.
A 7.1 gpm Noritz will get ~$1,200 and the install roughly another $1,200. With 30% tax rebate, it would roughly shave it $700 off, for $1,700 ball park. I also priced a modest tanked system and come in at ~$800.
I'm kinda between. Two tank units with a lifespan of 10-16 years or tankless...I need to dig through my utility statements. For those on natural gas...did you see an obvious drop in your gas bill at the end of year?
A 7.1 gpm Noritz will get ~$1,200 and the install roughly another $1,200. With 30% tax rebate, it would roughly shave it $700 off, for $1,700 ball park. I also priced a modest tanked system and come in at ~$800.
I'm kinda between. Two tank units with a lifespan of 10-16 years or tankless...I need to dig through my utility statements. For those on natural gas...did you see an obvious drop in your gas bill at the end of year?
ICUDoc
Enlightened
We have had tankless for a few years. There was a small saving in gas use initially, then the little ones became teenagers....
Discipline in water use is paramount: then you save, otherwise it's MORE expensive as you can enjoy "water hot down the back" for long, long time!
Our saving was of the order of 15% on a storage system. We have a 24 litre (6-odd gallons) system.
Overall, I'd do it again- I especially like the dial-a-shower-temperature option!
Discipline in water use is paramount: then you save, otherwise it's MORE expensive as you can enjoy "water hot down the back" for long, long time!
Our saving was of the order of 15% on a storage system. We have a 24 litre (6-odd gallons) system.
Overall, I'd do it again- I especially like the dial-a-shower-temperature option!
Linger
Flashlight Enthusiast
We put a Renai (sp?) tankless in the vacation property. It wins for a few reasons - its more efficient then a tank for simply heating water for use, additionally it doesn't waste heat keeping a tank-ful at tempurature. Best of all is the high flow-rate.
We've got 5 full bathrooms, and the 'unlimited' hot water is fantatsic.
We've got 5 full bathrooms, and the 'unlimited' hot water is fantatsic.
We and other family members have Bosch instantaneous water heaters complete with wall mounted temperature controls, very convenient set the temp you like and just turn on the hot tap only for a perfectly regulated shower. If a cold tap is turned on or a toilet is flushed the change in temp is barely perceivable, great safety feature for the kids too. http://www.bosch.com.au/content/language1/html/1220.htm
Norm
Norm
Illum
Flashaholic
matrixshaman
Flashlight Enthusiast
Not sure where you are pricing hot water heaters but Lowe's has both electric and gas regular 40 gallon units for right around $400. If you turn these down a bit - especially in the warmer months they really don't use a lot of energy to keep water warm especially if they are protected in some way from extreme cold. I personally am energy conservative but I still prefer a regular hot water heaters over tankless. There are also a number of things that can be done to help regular water heaters be more fuel efficient. And if you do have to get an electric tankless they will take a huge amount of current when they turn on. So depending on the rest of your house wiring can mean a dip in power (think computer voltage dip/spike) which can be hard on electronic devices - again depending on your house wiring. Many houses will require replacing the main electric panel and possible even the incoming wire from the electric pole/transformer. Done right it can get expensive. Sorry but I'm 'thumbs down' on tankless units for most common replacement situations.
Sgt. LED
Flashaholic
:twothumbs I got mine from Lowes. Maybe being cheap was a better decision than I thought!
HarryN
Flashlight Enthusiast
I looked at the tankless types when I did the last water heater replacement. Electricity is crazy expensive in California, so that version was out.
As noted above, the tankless needs a high capacity gas feed (and exhaust) to keep up with its rating, and my house was plumbed for neither, making the gas retroft version rather expensive.
One approach I did consider, was to put in a standard gas fired tank heater, and then run this hot water through a smaller tankless electric type. The idea was to do the primary heating with gas, and then assist with the temperature slump with the tankless. This was to help overcome the "teenager shower" problem, as we did in fact run a lot of showers in short order.
We found ways aroud the general shower problem - a clock in the bathroom.
BTW - as noted above, all of the newer high efficiency water heaters use thin walls to improve heat conduction, so they don't last nearly as long anymore.
As noted above, the tankless needs a high capacity gas feed (and exhaust) to keep up with its rating, and my house was plumbed for neither, making the gas retroft version rather expensive.
One approach I did consider, was to put in a standard gas fired tank heater, and then run this hot water through a smaller tankless electric type. The idea was to do the primary heating with gas, and then assist with the temperature slump with the tankless. This was to help overcome the "teenager shower" problem, as we did in fact run a lot of showers in short order.
We found ways aroud the general shower problem - a clock in the bathroom.
BTW - as noted above, all of the newer high efficiency water heaters use thin walls to improve heat conduction, so they don't last nearly as long anymore.
Appreciate the input.
The overall initial costs of tankless eat me though the various financing makes it a bit easier. This is still an outlay more than desired. I'm thinking at this point, put in a tank, if it goes 8 years, re-evaluate how the tankless technology is then. I'm so wishy-washy who knows what I think in an hour.
:shrug:
As for the other water heater...I was very pleased with the longevity. Our plumber friend commented that some cities water is very nice so he's seen some in the 15-20 years with frequency. The new water heaters he stated aren't that good, every 8 years expect to do the routine, if it goes longer...lucky.
I've got a few calls I'm waiting on, by Friday providing the old heater doesn't drop out, I'll have to conclude this. As always, Murphy happens on weekends when it becomes very tough to schedule work and with X-mas so close...ugh.
Update
Two calls came through on the tanked water heater...$900 and $1K for a 40 gallon replacement. Ugh...this is more than anticipated.
The overall initial costs of tankless eat me though the various financing makes it a bit easier. This is still an outlay more than desired. I'm thinking at this point, put in a tank, if it goes 8 years, re-evaluate how the tankless technology is then. I'm so wishy-washy who knows what I think in an hour.
:shrug:As for the other water heater...I was very pleased with the longevity. Our plumber friend commented that some cities water is very nice so he's seen some in the 15-20 years with frequency. The new water heaters he stated aren't that good, every 8 years expect to do the routine, if it goes longer...lucky.
I've got a few calls I'm waiting on, by Friday providing the old heater doesn't drop out, I'll have to conclude this. As always, Murphy happens on weekends when it becomes very tough to schedule work and with X-mas so close...ugh.
Update
Two calls came through on the tanked water heater...$900 and $1K for a 40 gallon replacement. Ugh...this is more than anticipated.
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Sgt. LED
Flashaholic
IS SOMEONE ELSE INSTALLING THIS FOR YOU?
Way too much for a tank. $450 tank and parts tops.
Way too much for a tank. $450 tank and parts tops.
