Help me bathe. No wait. Help me have enough hot water. Yea, that.

December 30, 2009 10:39 AM

2 days to decide on a tankless water heater. Help!

So we just bought a house, and everything in it is ultra high efficiency minus the water heater...which is 25 years old and can barely heat enough water to take a 7 minute shower.

Natural Gas, plenty of pressure, 1" ID supply line, horizontal vent, indoor application.

So...between our $8,000 cash back and the 30% efficiency rebate + state incentives, we want to go tankless. Last night we went to Lowe's and grabbed the Bosch 1600H. It's on lowes credit, so no payments for 6 months (and the rebate check will be in before then, so no interest, plus we got a 10% off coupon from Lowes for moving, so $649-10%= like $589 or whatever.)(30% rebate = ~$165, so $424 total cost to us in the long run.)

We will be venting horizontally. The 1600H requires a fan assisted horizontal vent kit that costs *cough* $450, or available online for $379-$450. The vent kit is NOT eligible for the tax cut. We considered moving up to the next model (which is self vented), for like $1200, but the exterior vent mechanism is another $220 for that.

The amazon reviews on the bosch say in cold weather we'll be lucky to get 3gpm @ 120 degrees. The only thing that TOUCHES that kind of draw is the shower, and we can put on a new head. It uses a hydrostatic piezo ignition which is cool, (no energy use at all when not running), but the stinking vent will have to be wired anyway.

HomeDepot did NOT send us a coupon, but they have this Rheem for $999, and it's self vented and doesn't require anything extra, AND its 63,000 btu's bigger and seems to have better overall ratings. No interest free credit, but I think we can afford 1-2 months of $40 a month until the rebate check rolls in.

SO we've got choices:
1. Buy the vent kit for the little Bosch. (~$900 total cost to us.)
2. Upgrade to the bigger Bosch. ($1200 total cost to us.)
3. Return the Bosch and get the Rheem. ($999 total cost to us.)
4. Something else as suggested by metafilter.

Obviously, decision has to be made by tomorrow night b/c that's the expiration for the tax credit.

I'm leaning towards the Rheem, but I'd like to hear your input.

(Oh, our house is a 1920 4bed 1 bath brick. DW uses 4.9 gallons per load, washer uses none to speak of, 1 bathroom, 2 total sinks. No plans for more water-using stuff.)

Oh, and yes, I'm aware we could go tanked for cheaper and/or improve the one we have. We'll be vacating this house probably w/i about 5 years, so this kind of capital improvement should serve to improve our value while making it so we can fill a cast-iron clawfoot tub with hot water enough to cover my junk. (right now we can't.))

posted by TomMelee to home & garden (27 answers total)

Well, ok, $219 for the horiz vent kit for the Rheem. Amazon reviews not so hot...but I wonder at peoples levels of proficiency.
posted by TomMelee at 10:45 AM on December 30, 2009

I replaced a tanked water heater for a tank-less unit and was able to use the existing vent. My vent was vertical through the roof. Is your current system horizontally vented?

I had the Rheem model. My experience with hot water in the winter was to turn up the burner on the heater, in the summer I lowered it. We had 2 teenagers in the house along with my husband and never ran out of hot water. I was very happy with the Rheem model. I will never have a "tank" water heater again!
posted by JujuB at 10:59 AM on December 30, 2009

I'd still encourage you to think about a tanked heater. True, the shower is the only use you've got that wants that much hot water at the one time. But what if you want to use more than one shower at once? Or take a shower while someone washes dishes? You may well find that your capacity goes down to the point that there just isn't enough to go around. If you've got more than one or two people in the household, I'd say this is a real consideration.

The other thing to consider is that the energy savings for tankless v. tanked heaters can be pretty minimal. Like $50 or so a year, if you get one of the new efficient tanked heaters. This is especially true for gas tankless, like yours, which aren't actually as efficient as electric in this application, and require electricity for venting anyways, so it could take quite a while to make up that cost in utility savings. If you're going to leave within five years, you may wind up in the red on the deal.

Finally, check this link. The author points out, wisely I judge, that if you're in a cold climate and/or an area prone to utility outages, a tanked hot water heater can be a real life saver. Not only does it ensure hot water longer, but it avoids expensive repairs should a pipe burst in your tankless heater.

All in all, I'm just not sold on the concept of a tankless heater. Yeah, they're cool, but I'm not sure they're worth it.
posted by valkyryn at 11:00 AM on December 30, 2009 [2 favorites]

Call your local Home Depot and see if they will honor competitors coupons. That may help your decision.
posted by TooFewShoes at 11:07 AM on December 30, 2009 [1 favorite]

Valkryn's analysis is correct.
posted by dfriedman at 11:07 AM on December 30, 2009

Re: tanked/tankless, I have to say I'm less than fully impressed with our tankless heater. With a tank heater, as soon as the hot water is flowing, there's hot water coming. With the tankless if you haven't used the hot water in a while you have to wait for it to get hot. In short, in our kitchen (near the water heater) we used to get hot water in 8 seconds on turning on hot water. Now it's about 22 seconds. Similar for the shower, used to be 6, now it's 22. Even worse for the upstairs bathroom, it used to be 45 seconds, now it's over a minute.

Granted, I didn't time before we had the switch, so I could just be horribly misremembering. But at least the impression is that we're running the water a lot longer waiting for heat.

There are mini-tanks that one can get in front of tankless heaters, but I seem to recall they're silly for the price. If we ever move, a tankless hot water heater would be a negative point for the house for me.
posted by nobeagle at 11:07 AM on December 30, 2009

10% coupon at Home Depot if you sign up for the "Home Depot moving club" (see the "Get 10% off box on the left for more info). I don't know what the sign-up entails, or how quickly you get your coupon, but it's worth checking out.
posted by runningwithscissors at 11:10 AM on December 30, 2009

I realize that this advice might be too late for you now, but in the future, if you are having problems running out of hot water with a tank heater, turn up the thermostat all the way on the heater. You'll use less hot water to get the same desired temp and thus it goes farther. Of course, this is not good advice if you have young children in the house.
posted by marsha56 at 11:18 AM on December 30, 2009

I used to install hot water heaters, though I have never installed a tankless one. I have, however, removed several.

I agree with valkyrn. The tankless heater is a great concept, but I'm not convinced that they're cost-effective or better than a well-insulated gas-fired tradtional hot water heater.
posted by BitterOldPunk at 11:20 AM on December 30, 2009

Have you looked at online sources? I got my Stiebel Eltron tankless for less than half what my local distributor wanted. My online price was less than his cost. I got it two years ago & the energy savings (it's electric - not gas) have already paid for it.
posted by torquemaniac at 11:26 AM on December 30, 2009

runningwithscissors, nice find. I did sign up and it does look like they have the 0 payments for 6 months thing.

Re: tanked versus tankless...I'm aware of the pros and cons. Part of my job earlier on with a well known non-profit housing organization was cost/benefit analysis for tankless versus tanked water heaters.

I don't get power outages, I have one shower (even so, it's 2.7gpm or lower, and it's not 100% hot water), we wash dishes when nobody is home or we are asleep, and the difference btw 5 and 20 seconds for hot water isn't especially a consideration that we're worried about. Our basement area is conditioned...but nothing like the rest of the house. The benefits of an $800 highly insulated and timer-ed hot water tank are still, to my greatest estimation, not enough to consider them at this point.

The vent has to be horizontal. I'm not shooting pipe through 3 floors and an attic worth of space. ;-)

I hadn't especially considered electric. Both electricity and gas are pretty cheap here, a couple years ago I know people had had bad experiences w/ electric units. I can look at that angle too.

Keep 'em coming.
posted by TomMelee at 11:28 AM on December 30, 2009

I'm also happy to buy online. Thrilled even. Stories are useless w/o links though, feel free to memail them if you don't want to advertise for someone. Please?
posted by TomMelee at 11:33 AM on December 30, 2009

I had a tankless water heater installed in my two-story house in Michigan about eight years ago. I bought it at Home Depot, it is a Bosch Aquastar. It is the smartest thing I have ever done for my house. I love it, it has been problem free for me.

My unit is natural gas, and I put it in the basement where the old tanked water heater was. It is vented out the side wall, at ground level. I had to buy a new vent for this. The whole system and installation was initially expensive, but not really that bad. The bathroom with the shower is on the second floor, so the water has to travel two stories, but it isn't a problem.

Long story short---it has saved us tons of money on natural gas. Our natural gas bill dropped by 12% the first year. I have scalding hot water whenever I need it, and our outside temps here in Michigan can be very cold, at times below zero. I have never had a problem with the water heater ever. One issue though, was the water flow restrictor in the shower head, I had to tear that out. The velocity of the water flowing trips the pilot, and with a low flow shower head it defeats that. And you do have to wait for the water to heat up, but in my house it is about the same as it always was.
posted by chocolatetiara at 11:50 AM on December 30, 2009 [1 favorite]

We picked up th Bosch 27000ES last fall. It's an LP model, and it cost $1099 plus $220 for the vent kit . It is rated for 7.2 GPM, and we have had no regrets whatsoever. It was good for a $300 credit so the total comes to ~$1020. We did NOT get it at Lowes though, they wanted ~ $1500 for that model. Try calling around some Mom and Pop places.When it comes to hot water, Go BIGger or stay home. This is in Maine too, although we have a backup generator for power outages.
posted by lobstah at 11:54 AM on December 30, 2009

Or...I could do like, say, this (thanks for the insight to look at Stiebel Eltron, btw). 3, 60A breakers won't be cheap, but no venting and no exhaust gasses to think about, and the GPM flow on the thing is a little ridiculous.

Again, thoughts? Feel free to tell me I'm silly.
posted by TomMelee at 11:55 AM on December 30, 2009

Keep in mind that more efficient does not necessarily mean cheaper. Electric resistance heat is certainly more efficient, but it'll bleed you dry.

Also, if a larger unit is only marginally more expensive, do that.
posted by electroboy at 11:57 AM on December 30, 2009

Go for the larger tankless unit and enjoy it! I am infinitely jealous - we had to replace our hot water heater two years ago, and against my better judgment, I let my husband win the argument, so we went with a new tank instead of the tankless unit I really wanted.

We already run the dishwasher overnight, and can't have two showers going because we'll be out of hot water (or warm water, or anything but cold water) in 5-10 minutes. Most laundry is done in cold, and I generally do it during the day when no one else is home. Turning up the thermostat on the hot water tank is not an option, because we do have small kids and it's already at the upper safe limit for them.

And even with the new, bigger, "more efficient" hot water tank, I *still* can't get enough hot water to enjoy a bath in my jetted oversize bathtub. It's a quantity issue - doesn't matter that I have to wait 15 fewer seconds for hot water when I cannot, as you so eloquently put it, get enough hot water to cover my junk. Once the hot water tank is empty, it's empty, and will take some time to refill and heat up. Meanwhile, I'm frozen and mostly dry, and bitter about giving in to my husband's penny-wise, enjoyment-deficient argument.
posted by Lulu's Pink Converse at 12:35 PM on December 30, 2009

Part of my job earlier on with a well known non-profit housing organization was cost/benefit analysis for tankless versus tanked water heaters.

That's great. Were you evaluating them for other people to have or to freeze your own rear in the shower?

There's a previous AskMe I used when debating the same subject. The one thing I can say for sure, if you do look at a non-vented option, is do not even think about a Bosch ProTankless GWH 425 HN. We have one (professionally installed) and it's terrible, even with just two people in the house. It's slow to deliver hot water and it's been weird enough that our plumber (a sweetheart of a guy) spent a couple of days fooling with it months after install (on his own dime) and had to have the Bosch factory reps out a couple of times to figure out some thing that could never go wrong did.
posted by yerfatma at 12:40 PM on December 30, 2009

I have a Rinnai 75lsi and it has performed flawlessly for us for over a year now.

I live in a northern climate and our incoming water is very, very cold. I've never had a problem with the water not getting hot enough. I have no problem hopping in the shower while the dishwasher or washing machine is running (the temperature fluctuates, of course, when the appliances are using water, but it never gets cool).

It doesn't take too long to warm up.

If I were you, I'd go with the Rheem.
posted by davey_darling at 3:10 PM on December 30, 2009

I put two tankless heaters into my house. The smaller is 117 kbtu/hr and has a standing pilot - this is about the size of the Bosch you linked to. On a cold morning with 40 degree incoming water you can shower with this, no problem. The larger is 165 kbtu/hr and two showers work at the same time - no tricks with restrictors, either, these showers make you feel as though you're being hosed down.

Both heaters are Bosch, went in in 2003, and have been pretty good though not completely trouble-free.

When the time comes to replace them I will opt for very simple water heaters like the Paloma legacy series. These control the mixture with a device like a Zenith-Stromberg carburetor and are easy to fix, but don't need much fixing. Computer-controlled water heaters are not happy with the garbage electrical power we have.
posted by jet_silver at 3:56 PM on December 30, 2009

A small but potentially important point: I have never had a problem getting Home Depot to take Lowe's coupons. It is their policy at least locally, and from what I have seen online it seems to be pretty widespread if not universal.
posted by RikiTikiTavi at 4:39 PM on December 30, 2009

Thanks everyone for your input. I *think* we're going to order the large electric I linked to earlier, based on the temp of our incoming water, the fact that it doesn't require a vent, and the fact that our large panel has more than enough room for 3, 2 pole 60A breakers.

Again, thanks everyone for your opinions pro and con.
posted by TomMelee at 4:50 PM on December 30, 2009

A larger, possibly important point:

The Energy Star site says that the tax credit expires December 31, 2010. I looked 'cause I was bummed at missing it.
posted by RikiTikiTavi at 4:56 PM on December 30, 2009

not sure if this is applicable to your situation but one point worth mentioning - you can set the hot water temp of the tankless to a lower temperature (about 114 deg F) than that required for tank heaters (no need to heat the water to a temp that will kill bugs etc with a tankless because the water is not standing around). this is a useful feature if you have small kids and want avoid any bathtime scaldings...
posted by SueDenim at 5:04 PM on December 30, 2009

I purchased a Palmoa, which became Rheem, back in 2006 when I bought my house. Recently, the control board on it failed, and I had to call them for support. Support was excellent, they took the make & model, and mailed me the new part overnight with no cost or hassle. It came with instructions to install it myself, although I had a service contract with my HVAC vendor, so I asked them to pop it in for me to be sure, and check everything else out while they were there.

Good support is key for me. When you lose your hot wated in the middle of late fall / early winter, you do NOT want to get stymied by poor support from your vendor. Rheem held up for me. I can't comment on Bosch, however.
posted by GJSchaller at 9:00 AM on December 31, 2009

you can set the hot water temp of the tankless to a lower temperature (about 114 deg F) than that required for tank heaters

This will affect how well your dishwasher works. Assuming you haven't out-sourced the washing of dishes to some fair trade organization that mails them back.
posted by yerfatma at 12:51 PM on December 31, 2009 [1 favorite]

I LOVE my Rinnai (gas, don't know the model) -- been about 4 or 5 years now, and I shudder to remember the days when we couldn't fill our tub with hot water. (Not claw-foot or jetted, just a boring smallish bathtub.) And our tanked heater wasn't all that old, maybe 10 years?

I did some research on gas v electric, and the cost of gas was enough less to stick with it. We had ours put on the outside of the house under the eaves, so all the venting was directly outside; with brick you might not be able to do that. We had it installed because no way do I screw around with gas stuff. I wouldn't go with Lowes for that, though; we almost had a tanked heater installed by them, and it was such a lousy experience that we just had them take the water heater back uninstalled.

As for doing things at the same time, I've found that, no, you can't generally run the washer (if hot) or do dishes at the same time as you take a shower. Then again, that hasn't been much of a problem. The slow heating thing has been more obnoxious, but we manage. If we redo the bathrooms/kitchen we'll be looking into minitanks or something, just for that first minute. The wasting water irritates me more than the waiting.
posted by epersonae at 4:17 PM on December 31, 2009