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lowell holmes
01-01-2011, 6:01 PM
Is there a knowlege base here about tankless water heater maintenance?

Thanks,

Lowell Holmes

Bill Cunningham
01-01-2011, 9:50 PM
There was some talk about them a while ago.. I have one, and I think the only maintenance is to de-lime them by shutting down the main valves, and pumping a descaler through the bypass valves into the system (CLR might work well).. If you live in a hard water area, or draw from a well you may have to do this quite often. Our town water source is lake based, so it's really soft water, and we don't even have to descale the coffee maker..

lowell holmes
01-01-2011, 10:32 PM
Thanks for responding.

Dave Beauchesne
01-01-2011, 10:49 PM
Lowell:

I am a gas fitter and have worked on quite a few, albeit never in areas with really hard water.

The beauty of them is that due to the fact they do not store water ' hot ' , the minerals that usually percipitate out in the form
of scale is not nearly as much of a problem as a tank style storage type water heater.

Hope that makes sense.

Dave Beauchesne

Bryan Rocker
01-02-2011, 12:54 AM
I have been looking into tankless water heaters as well. Here in my area of Ohio, the water is extremely hard. I have looked at the whole house variety and it looks to me like propane will be the only real option for me. Gas is not run up the streeet and electric just won't cut the mustard. I wonder how well these run on softened water?

Chuck Stewart
01-02-2011, 8:54 AM
Thanks for the reminder Lowell, I remember my Rinnai owners manual said to flush the lines once a year and I'm just over that ,something about taking a couple buckets, one with the descaler and re-circulating thru the lines for about an hour....now where's that darn manual?

John Shuk
01-02-2011, 11:50 AM
http://www.rinnai.us/documentation/downloads/ES38_1004RFA_Manual.pdf
This may not be your unit but I'm sure you can find it here.

Mike Hollingsworth
01-02-2011, 12:04 PM
Every time I've ever replaced a water heater, it's been at least 15 years old with no maintenance. That WILL NOT happen with a tankless. At half the price, I'll stick with the old technology.

Bill Cunningham
01-02-2011, 1:32 PM
I also have a Rinnai; Yes, they are expensive but the advantages of tankless are never running out of hot water, and cheap cheap cheap to run.. Mine supplies ALL our hot water needs burning only 1/2 cubic meter of gas a day. (about $0.17 worth) My old oil fired tank heater was also very fast, but burned $1200.00 in oil a year for the same amount of hot water. That's more than 1100.00 a year savings, and pays for the Rinnai in less than 3 years. Keeping 40-50 gal of water at 120 degF 24/7 is not cheap no matter what your tank burns..
Even if you live in a hardwater area, the occasional flush is not much of a problem. After 15 years a tank in a hard water area probably has 50-100 lbs of crud in it sucking up your heat energy and taking the place of usable water.. Old technology may be cheap to buy, but you pay more in the long run..

Mark Bolton
01-02-2011, 2:44 PM
Every time I've ever replaced a water heater, it's been at least 15 years old with no maintenance. That WILL NOT happen with a tankless. At half the price, I'll stick with the old technology.

Where is your data to back that up? On demand water heaters, even those of old, commonly exceed the life cycle of a tank type water heater for dozens of common sense reasons. Cycle times are minimal in comparison, component usage is minimal in comparison, and as has been stated mineral precipitation and scale buildup is minimal in comparison. This is all couples with fractional fuel consumption costs.

Would be interesting to see your data...

Mark

Mark Bolton
01-02-2011, 2:57 PM
I also have a Rinnai; Yes, they are expensive but the advantages of tankless are never running out of hot water, and cheap cheap cheap to run.. Mine supplies ALL our hot water needs burning only 1/2 cubic meter of gas a day. (about $0.17 worth) My old oil fired tank heater was also very fast, but burned $1200.00 in oil a year for the same amount of hot water. That's more than 1100.00 a year savings, and pays for the Rinnai in less than 3 years.

And you are talking about a high priced unit that requires a proprietary installer. Not to say Rinnai is not a top of the line unit, it absolutely is. We have installed Rheem units, which are made by Paloma for Rheem, and have one in our own home. Speaking from our personal experience, we have a Rheem RGT53P, propane unit. There are only two of us in the house but we are running this unit of a pair of 100LB propane tanks. Our DHW costs are less than $50 per year. This is from a unit that does NOT require certified installation and is about 1/2 the cost of a Rinnai (not slamming the Rinnai in any way). We payed $600+ for our unit and then an additional $150 or so for the venting components.

There is simply no way a tank style water heater could touch the performance of one of these units. A 40 gallon Nat. Gas water heater (just purchased a 40 and 50 for a job) are approximately 385.00 plus tax in our area. If you purchase from a home center they will be more like 450.00 and up. Add the flue components to our cost and you are in the 450.00 range. The fuel consumption will offset the 200-300 dollar difference in up front costs in short order and the lifespan of a tankless vs. tank type is not even in the same ball park.

Mark

Paul Grant
01-02-2011, 4:51 PM
I have a Rinnai tankless also. Be very wary of the cleaning of these units, they DO need to be flushed routinely and are VERY sensitive to scale build up. Get in the habit of an annual flush or better and if the "clean" signal flashes on the unit get on it right away and you'll have a couple decades of trouble free operation.

Bill Cunningham
01-06-2011, 11:29 PM
I had my Rinnai installed with a full package (3 stg furnace, 2stg 19.5 sear ac/hp, and the Rinnai) I think the Rinnai lists for about 3k here.. My whole setup was 18k (fully installed, you don't mess around with gas yourself)and I got 5500 back in rebates, and dropped my heating & hot water costs for both the house (1 story 1200 sqft) and the shop (two story 1200 sq ft) from 3000+ a year total to about 1000 +/- total for gas(shop) & gas/elec. (house) Which gives me about a 6year payback, and it has a 10 year parts and labour warranty.

Colin Giersberg
01-07-2011, 12:02 AM
We had a Rinnai whole house unit installed this past summer. It wouldn't hurt to check with your utility company to see if they offer tankless units for a significant discount. Our utility sells them for $775 for the unit that we have, which is roughly half price. The only stipulation to getting it was to have city water, which we do (we live just outside the city limits). The problems we had with getting it installed was that the guy that hung the unit would not vent it. We had to get another plumber to install the gas line and yet another one to install the vent after we found out that the guy doing the gas line didn't install vents. Then there were the two guys to swap out the meter. It turned out that we had to have a bigger meter to supply the unit , as well as our gas log fireplace. All in all, it took six men to get our installation done. Had we checked around, we would have found out that the plumber who installed the vent could have done it all. Total cost was around $1400.

Regards, Colin

Mike Cutler
01-07-2011, 3:04 PM
Every time I've ever replaced a water heater, it's been at least 15 years old with no maintenance. That WILL NOT happen with a tankless. At half the price, I'll stick with the old technology.

Mike

The payback is more than just the price of the heater. For us, here in Connecticut with the 2nd highest electric rates in the country, the payback is the overall savings on total utilities.
Now that the state has found a creative way to add an additional tax, via the electric bill this, anything that decreases the electric bill decreases my total taxes.
Currently I have an electric hot water heater, but it will be replaced in the next few months with either a propane on demand unit, or a propane storage unit

Jim Becker
01-08-2011, 6:22 PM
I'm a believer. Our addition has a tankless water heater--a big Bosch in our case. It's been steller having essentially "unlimited" hot water. I'd put one in the other side of the house, but as I've explained here in the past, the nature of that part of the building prohibits venting in the required way at the current time, so we have a high-efficiency "shortie" 50 gallon tank type in use over there. The only issue we've run into with our tankless unit is with the guest shower head...it doesn't flow enough water to keep the heating element running. The minium flow rate for the particular unit we have is .8 GPM. In my copious free time, I'm going to "adjust" the shower head (which is rarely used) by drilling it out. In the mean time, a guest or one of our daughters using the shower just has to turn on the hot water in the sink at the same time. A little wasted water, but that's the way it is.

Bill Cunningham
01-08-2011, 8:33 PM
I'm a believer. Our addition has a tankless water heater--a big Bosch in our case. It's been steller having essentially "unlimited" hot water. I'd put one in the other side of the house, but as I've explained here in the past, the nature of that part of the building prohibits venting in the required way at the current time, so we have a high-efficiency "shortie" 50 gallon tank type in use over there. The only issue we've run into with our tankless unit is with the guest shower head...it doesn't flow enough water to keep the heating element running. The minium flow rate for the particular unit we have is .8 GPM. In my copious free time, I'm going to "adjust" the shower head (which is rarely used) by drilling it out. In the mean time, a guest or one of our daughters using the shower just has to turn on the hot water in the sink at the same time. A little wasted water, but that's the way it is.

My 'guess' is that the shower head is one of those water conservation type heads.. The local utility came by and offered to install them in our house for free.. Well, 'free' is a pretty good price so I said go ahead.. The following day, my wife and 'last at home' daughter, demanded that I remove it.. The problem seems to be, a woman with long hair, (they both have long hair) cannot seemed to get it rinsed properly with one of those 'watersaver' heads.. One of those nice big 'rain', sunflower, or flow adjustable type heads works better for them. The water saver heads are now just in a drawer, and I guess the planet is a little worse off because of 'me'

Mark Bolton
01-08-2011, 9:22 PM
My 'guess' is that the shower head is one of those water conservation type heads.. The local utility came by and offered to install them in our house for free.. Well, 'free' is a pretty good price so I said go ahead.. The following day, my wife and 'last at home' daughter, demanded that I remove it.. The problem seems to be, a woman with long hair, (they both have long hair) cannot seemed to get it rinsed properly with one of those 'watersaver' heads.. One of those nice big 'rain', sunflower, or flow adjustable type heads works better for them. The water saver heads are now just in a drawer, and I guess the planet is a little worse off because of 'me'

I think it actually depends on which low flow head you use. We had a similar problem with a tankless unit as Jim and just removed a "widget" from the head which made it a little higher flow head but still a water saver head. It allowed enough flow to kick on the tankless but is still far less than one of the guzzler sunflower heads you mention. The heads we install most are the (think they are called) miracle heads. Little chrome head on a card at the hardware store. Oddly they are very low flow but very few people have ever commented to us that they feel jipped of water when they shower. My feeling is a lot has to do with the water velocity and concentration as opposed to volume especially when it comes to rinsing your hair. Just imagine your wife/daughter rinsing hair under a garden hose with no nozzle, wide open, bubbling on their head, perhaps 5 gpm. Then imagine putting a nozzle on their and blasting it at their head in a jet or concentrated spray pattern (conjures up a funny visual) perhaps 1 gpm. I bet they would rinse their hair faster, and better, with the nozzle.

There are actually some interesting studies that have been done on water saver heads in the hotel industry. It has been the common argument that if you install a water saver head you will take longer showers because you are getting less water and it will take longer to get clean and rinse. The majority of the studies showed this to be untrue in blind tests in that people who had no idea if they were showering with a water saver or a water waster took shorter showers when using a water saving head. This meant not only did they use less water while showering, they took a shorter shower as well.

That said, my wife too has long hair and arguing with her about the time it takes to rinse it is basically pointless.

As a side note, I watched an interesting show on History channel the other night where they had I think six guys who were all round tabling what the worlds biggest threats are, nuclear terror, financial collapse, peak oil, and so on. What was interesting is that by the end of the show there was pretty much a consensus that it wasnt going to be oil, power, terror, and the other commonly thought of threats that would be confronting us in the future. The consensus was that water was going to likely be one of the major hurdles we will face. Interesting to hear these guys talk about things that many of us have been talking about for years, water conservations, growing food nearer to where its consumed, producing things closer to where they are purchased/used, and so on.

Something we all take for granted in this country, water, could likely be as big a player as foreign oil.

Mark

Mike Cutler
01-09-2011, 7:52 AM
I used to take a shower head, crescent wrench, channel locks and teflon tape with me, when I travelled. First thing I did in the room was remove that "water saver" head from the shower in the hotel room and install my "real one".

Jerome Stanek
01-09-2011, 7:56 AM
I'm a believer. Our addition has a tankless water heater--a big Bosch in our case. It's been steller having essentially "unlimited" hot water. I'd put one in the other side of the house, but as I've explained here in the past, the nature of that part of the building prohibits venting in the required way at the current time, so we have a high-efficiency "shortie" 50 gallon tank type in use over there. The only issue we've run into with our tankless unit is with the guest shower head...it doesn't flow enough water to keep the heating element running. The minium flow rate for the particular unit we have is .8 GPM. In my copious free time, I'm going to "adjust" the shower head (which is rarely used) by drilling it out. In the mean time, a guest or one of our daughters using the shower just has to turn on the hot water in the sink at the same time. A little wasted water, but that's the way it is.



In other words you have to turn the water all the way up to to get hot water so what you save in gas you pay for in water.

Mark Bolton
01-09-2011, 10:26 AM
In other words you have to turn the water all the way up to to get hot water so what you save in gas you pay for in water.

I think reaching 0.8GPM for the heater cut-in is far from "turning the water all the way up". While it would of course be better not to be running water down the drain in the sink to be able to shower, I have had more temporary fixes for a intermittently used something or another than I care to count so I can sympathize. Maybe Jim will hustle up and swap that shower head now.... ;) Our unit has a slightly lower cut in of .5GPM.

Mark

Phil Thien
01-09-2011, 12:24 PM
I used to have one of these shower heads:

http://www.alsons.com/classic/economy_showerheads/products/654.aspx

2.5-GPM is a lot of water. But the thing actually felt like you were getting hit with a fire hose. I had people stay here and stay in the shower until all the hot water was gone. Repeatedly. And they'd say things like, "wow, that shower kinda hurts, in a good way." My friend got one and declared it was like "sandblasting for the body."

In any event, when the kids got older and I got tired of their 30-minute showers I removed it and replace it with a lower GPM shower head. The alternative was installing a tankless. And I didn't see the point in spending that money so they could live in the shower. What is the old saying, "when you're clean, get out of the shower?"

Greg Peterson
01-09-2011, 1:36 PM
My Takai unit kicks in at 0.6 GPM. And yes, it may take and extra second or two to get hot water versus a water tank unit, but after sitting still all night, the water pipes (or PEX lines in my case) need to be flushed of the cold water they hold anyway. I had to wait several seconds to get hot water in the shower with a tank, a few more seconds is not that big of a deal.

I am more than happy with our tankless unit.

Scott Shepherd
01-09-2011, 1:46 PM
I don't have one, but I do listen to a local home improvement show on the radio fairly often and the guy is a plumber by trade and he's answered the questions about 1000 times that I have heard. One thing he frequently tells people is to spend the extra money (not a lot extra) to have some "kit" installed that allows for easy flushing. Apparently it just adds a couple of points to the system you can freely access and makes life easier for those that have to flush them (which he also says is a must).

I don't know if that means anything to anyone (it means nothing to me), but maybe it's something to ask about (the flushing part of it) when you are shopping for them.

Jim Becker
01-09-2011, 7:40 PM
My 'guess' is that the shower head is one of those water conservation type heads..

It's actually a somewhat expensive Kohler setup and a low-flow design as is pretty much normal these days. Apparently, it's a "too low flow" model. LOL The problem is fixable as long as I eventually remember to actually deal with it. ;)

Jim Becker
01-09-2011, 7:43 PM
In other words you have to turn the water all the way up to to get hot water so what you save in gas you pay for in water.

Nope. We don't "pay" for water, per se, as it comes out of our well, outside of electricity to run the pump. And in actually, this particular shower only gets used, perhaps, a dozen times per year. And don't forget I mentioned running the sink tap is just an accommodation until I remember to fix the shower head to add a little more flow to it.