Tankless Water Heaters

[lowell holmes]

Is there a knowlege base here about tankless water heater maintenance?

Thanks,

Lowell Holmes

[Bill Cunningham]

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]

Thanks for responding.

[Dave Beauchesne]

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]

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]

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]

http://www.rinnai.us/documentation/d...RFA_Manual.pdf
This may not be your unit but I'm sure you can find it here.

[Mike Hollingsworth]

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]

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]

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]

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]

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]

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]

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]

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