installing tankless hot water heater

s.brown

Jack, can I email you or you email me back? I have an installation that I just inherited and could use some of your expertise.7,000 sq. ft. house and there are 3- C85i-1 propane units installed and I have a bunch of questions. Can you help me?
Thanks,
Shane

joel_29

tankless hot water heater

like the idea if tankless hot water heater but unsure if it will be enough hot water for our home. looking around and it almost sounds too good to be true. Is it good for long island,ny ground water temperatures? have a 2bath house what size unit would i need.looking at titan units.any ideas or suggestions would be great!

Derheatmeister

Boiler or Furnace?

What kind of Heat source do you have for the House?

A Furnace(Scorched Air)or a boiler with Baseboard?

If you have a Boiler then you are better off with a Indirect fired Waterheater

kpc_70

need more info.

what do you have now? how many baths? How many kids(esp. teens)... is the current set up near the baths or far away? How long will you be at this home? the pa back on these units is not short... they are def. more money than the currect gas tank heaters...esp. nat. vent set ups....kpc

Mad Dog_2

Hello there.............We install the Rinnai Tankless system...

and have been VERY pleased with them.  We have dozens installed over the last several years and have had ZERO problems with them.  If they are sized to your h.w. demands and piped correctly, they will NOT run out of hot water - GUARANTEED!  Our clients report significant savings as well.  The gas utilities also give a nice rebate.  If you click on to our Find a Professional Link below, that ad, has a link to our personal website.  When you go there, you will see a sidebar entitled "tankless water heaters"  This will explain how they work.  We also have some pics there.  On our home page we have a link to Rinnai.  At your service if you would like a firm quote.  Mad Dog ( I don't bite!!!!)To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Dan C.

I agree with Mad Dog. We install Rinnai's also. As long as you use them in the correct application, they are great!

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Derheatmeister

Bursting Bubbles

I hate to "Burst Bubbles" But:

Yes Paul Harvey did a Great job in promoting this product!

I am also a Registered Installer which is not a big deal!

The reasons for NOT installing the "On demand" waterheaters by far out weight the reasons why to!

But there are some situations were these Waterheaters May be justified!

The reason Why NOT:

1. Minimum Flow Rates:These waterheaters require a minimum flow rate to activate the burners which will Modulate depending on the requirements!(Wastes Water and is not very Green)

2. Again Wasting Water: You will waste a lot's of water /$$$ in waiting for the warm water to show up at the Fixture and one may argue that this is the case with regular waterheaters as well which can be resolved with a recirc pump line .Recircing a "ON demand" is pointless..

3. Annual service Required:Just like a Coffee Maker these Require that you "De Calcify" the Heat exchanger which will cost a certain $$$ (Not for free and there goes your savings!)

4. More Moving Parts: Although these units are build nice and do not have many problems ,they will in due time require repairs! i.e Blowers/ Gasvalves/Limit switches/Controls. I am more of a KISS kinda guy..

5. Multiple Units required: if you have Multiple showers and washing machines/ dishwashers going at the same time the unit cannot handle this! so you will require Multiple Units (depending on you incoming water temperature) which will increase the installation cost and the servicing thereof as well!

6. More Vents: Yes they may be side wall vented, but if Meters electrical equipment/Decks/Overhangs/Window are close by then you may have to vent away from these which again cost more $$$

7. Inefficient:These waterheaters are "Only" up to 87% efficient so that they will not condense!

Yes one may argue that this is much More efficient that a regular Waterheater and it's Standby losses, but if you take a Modulating Boiler at the Mid 90% efficiency and hook up a indirect fired waterheater (or sidearm as they call it on the east coast) you can produce hot water at close to the boilers efficiency without the fuss around it!
even if you do not have or are not planning on installing a high eff.boiler and have a regular 80+ boiler you still may consider interfacing it with an indirect as it will also Exercise your boiler in the summer thus keeping the circulating pumps from locking up!
If you want to save $$ and the environment you may (depending on your roof line and exposure ) install a Double coil indirect Tank an interface it with a solar system!!
Just some Fact's about "On demand waterheaters"!
Hope i could help! Richard Graves from Heatmeister

Edit: If you have a furnace that is older and you are thinking of replacing it soon anyway you may consider using a High eff. boiler in conjunction with a Air handler/ Air to air/AC and integrate this with a double coil Indirect/Solar interface...

Even if you have Steam system there is a way to Install an Indirect on the Condensate return, but yuall on the East side of the US of A shall know this better ehh?

Mad Dog_2

I don't float around in the clouds inside bubbles.......so...

no bubbles to burst here, Richard. Got my two feet on the ground (living in reality) They are NOT for every application and that is true, but that is why we look at each job for the best fit. We have talked clients out of using them when it is impractical. We have seen the additional cost payback to be 3-4 years. They take NO LONGER to purge the cooled water out of the hot water supply line to the faucet than does a standard water heater...and how many residential homes actually have a h.w. recirc? Dreamland......They are safer than atmospheric water heaters that will BLINDLY spill flue product in to the space if chimney is blocked becuase they have NO SAFETIES built in. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Erich_3

Look at a Navien On Demand Water Heater

mark ransley

deheatmeister

2 You waste no more money than with a tank, your argument is pointless
3 This depends on water hardness of water , did you ever hear of water softeners?
4 The coils should last 20 years, my AO cyclone has more parts than my Bosch tankless
5 Not if it is sized right and demand is within range
6 You completely for what the chimney is for
7. Here you are just full of total Crap. Water heaters are rated by EF Energy Factor, tankless go from 82-94 EF no tank comes close unless its condensing. Tanks are from 55- to near 84 EF even for a Vertex. My cheapo Bosch is 83EF and condensing Takagi are near 93EF. Tankless blow away tank in EF rating.

But ground water temps and gas supply must be measured, yoy may need major new gas piping. If its a large family and alot of water use a AO Smith Vertex HO 50 would be my choise and i have a tankless. Savings go down alot with greater usage with tankless. Alot of calculations are needed to size tankless where demand is great. Rinnai, Takagi make good units you should review. You will likely need a 225000 btu unit, that needs maybe more gas supply than your heating system. AO makes great commercial tanks.

Derheatmeister

UP here in \"Dreamland\" Colorado

most new construction has a Recirc line installed!

I guess that we here in the Rocky Mtn are just Way to Much :-)

I Germany it is Mandated since the 1980 ties!

Grundfoss and Taco offer retro installation kits that are petty cool and will save the customer literary Multiple hundreds of Dollars each year.. you may want to check these out! but you most likely know this! :-)

Relax..you may want to take a chill pill/Beer or whatever floats your boat first and then read my post's

I DID NOT say that the "On demand" water heater take longer to purge the cold water out of the lines that does not make any sense!

I can respect that you Turn down the install of "On Demand" as it is not for every situation!


Matt ,again this is hopefully not a personal thing?? I have not had the pleasure of meeting you in person,and did we have Beers yet!

As far as i can tell from some of the pix that you have posted in the past your jobs are clean and look like you put some(German pride?) into them as well!

ME tells me that you are a pretty cool guy!

Peace Richard :-)

Erich_3

Look at a Navien On Demand Water Heater

You will be better off with a Navien Model A water heater. It has a circulator and buffer tank and it is 98% efficient. Look here:

http://www.navienamerica.com/

It is made by one of the largest boiler manufacturers in the world. It does not waste water and it will give you endless hot water. In addition there is no minimum flow rate.

Jack

Well, let's see...(longish)

My normal disclaimer first, it is my pleasure and great good fortune to represent Rinnai for the last 18 yrs.

I considered writing this when Paul Harvey's passing was noted here a couple weeks ago. The way Paul Harvey came to the promoting Rinnai was that upon returning to his Scottsdale home one day he found that one of his hot water heaters had failed and made a mess of the place. To his plumber he said, "There has to be a better way". His plumber replied, "Well, I just returned from this seminar on these Rinnai's..." "Let's try that" says Mr Harvey. A couple months later, Rinnai received a call from the network saying that Mr Paul Harvey would like to see a representative from Rinnai at his home, at this time, on this date. "Will you be there?" "Yes", says Rinnai!

As you know, Mr Harvey promoted only what he used, knew and had personal experience with. As the conversation went, Mr Harvey said to Rinnai's Sales and Mtg VP, "when you consider the energy savings and look at the national implications of this product, it is enormous". He went on to say, that, while he "was an old man he could still make some tracks in the sand", on this energy saving topic. He was correct. This was related to me by the man who met with Mr Harvey. On his first broadcast I remember smiling when he said he was "so very thankful to the plumber who had brought Rinnai to his attention." I smile because Mr Harvey had endless, sufficient and efficient hot water as well as a couple extra million bucks. What a guy!

In response to some of the other points:

1. Minimum Flow: Yes there is a minimum flow. On our units it is currently .6gpm, but will be going to a lower rate soon. As with any new appliance, you get used to using it. If you open the faucet to a trickle, you will not get hot water. If you open the faucet to at least the minimum flow you will fire the unit and then you can turn the vol down to the level you need. My Rinnai will hold operation down to .3-.4 gpm. You can read that flow rate on the touch pad for confirmation. After a few days of working with it, most have no problem. It is different, but most people can deal with it. that is especially so when explained by the certified installer.

2. Wasting water: I'm currently re-modeling the Master Bathroom. After 8 years of living with my Rinnai, due to the construction process I went back to my indirect off the boiler for this winter. Next weekend, I'm installing the new Rinnai and happily turning off the indirect and disposing of it. In my home, with no re-circ, it takes 45 seconds first thing in the am to get hot water, with the Rinnai. It takes 40 seconds with the indirect and that is purely a piping difference. I will be adding a Metlund recirc and reporting on that in the near future. I recently began representing them also. Any reduction in water waste, or delay with a tank is from a constant thermosiphon within the piping, which increases energy consumption. The trick is to design a system which neither wastes energy nor water.

3. Annual service: Personally, I haven't touched my Rinnai in 8 yrs except to clean the inlet filter after the town flushes the hydrants. We have clean and good town water. If you follow Rinnai's installation instructions and check to make sure you have decent potable water then you too can enjoy years of trouble free use. If not...well, you are crapping up your tank water heater also.

4: More moving parts: Absolutely! In 45 yrs in the business as either an appentice carrying the journeymans toolbox down the street (I really did that;), journeyman, mech contractor or rep, I've never seen as reliable a piece of equipment as a Rinnai. I've sold more Rinnai's than anyone in North America. Everything in the box is made by Rinnai. It is their flow control, their modulating gas valve (they were the first in the world to make one), their burner, hx and they make and program their own pcb. All the individual components are friendly with each other. Yes, there are more components and it is why being a certified installer is a big deal. If you follow up on the certification step and attend the follow-up tear down trainings you will be a better mechanic when you leave the training that when you went in and better able to take care of your customers with Rinnai water heaters. So it isn't a throw away appliance like a tank water heater.

5: Multiple units: Perhaps! I've never lived in a house or apt that the dhw system didn't have its own personality. We hope it is more Jeckel than Hyde, but again, that is why we used trained installers. You have to qualify the use, explain the output as either a feature or it can be explained as a liability, if you choose to do so, but you must educate the consumer on its output capability and overlay that on how they use the system.

Tankless water heaters are all about flow and temp rise. I never tell anyone how many bathrooms they can run. I will tell them that an R75LSi at a 70f temp rise will produce 4.3gpm 24 hrs per day. How they use it is up to them. Is it enough? That is why we trained installers.

I once had a guy (homeowner) get pissed off at me for telling him his 25gpm shower was going to take 5 units. I said, "hey, mac, you built the damned thing, this is what it takes to feed it." The advantage of the Rinnai system is that when he wanted to use the bizarre shower he had capacity as long as he had gas, water, elec and septic capacity (kaboom), and when he shut if off it was OFF. When jr washed his hands, with a min. of .6gpm, that was all the water it provided and the system modulated from 15k-900kbtu. Pretty cool. Very cool to install and watch it work!

6: More vents: One per unit seems reasonable. Direct vent, pipe in pipe, zero clearance, 5" od is pretty neat imho!

7: Inefficient: All I do with gas in the summer months is dhw. When my girls were home, we used between 36-44 therms/mo. When I turned the boiler & indirect off and the Rinnai on, for the past 8 yrs I've been using 10-13 therms/mo. That is significant to me.

Rinnai's do not condense and are rated at a .82EF. We will have a condensing unit soon, but I have to say, I'm not sure it is for everyone. I'm absolutely a high eff guy and support it. I'm kinda surprised that I say this, but if you look at how people actually use hot water, typically very short duration draws, I'm not sure you will see significant savings using the condensing hot water unit in the average home. For extended vent runs and high duration loads, absolutely.

My suggestion for a system is to get the smallest condensing boiler you can to meet the heat load. When the heating season is over, turn it off. Get the right Rinnai water heater AND PUT IT IN THE RIGHT LOCATION. In other words, don't compound or extend the application mistakes of the original low bidder.

As to the Navien, they do not have good temperature control. They spike. Take the cover off one and hit the right codes on the board for output temp and watch it. They overshoot. We put output temp and flow info on the controller on the front of the unit for ease of use. Rinnai will be +/- 2F. If we exceed 6f over setpoint the unit shuts off. Safety first!

To have precise temp control you must have three things. A modulating flow control, a modulating gas valve and a cold water by-pass. They lack the by-pass and therefore lack good temp control.

Tanks vs tankless: Obviously my choice is clear, but I would like to ask the installing contractors here how many of the water tanks that you pull do you cut up and show the homeowner what is inside their water heater. My guess is that if you did so, and showed the homeowner, you would sell fewer tank water heaters.

[Deleted User]

jack, like emeril's, BAM!,

kicked it up a notch

a neighbor is using a rinnai for his radiant, and i'll be watching over the years

Dave Yates (GrandPAH)_2

Most popular article ever for Fine Home Building

At least that's what the editors said. It's the same info given to our customers when they ask about a tankless vs a tank style water heater.

http://www.taunton.com/finehomebuilding/PDF/Free/021191068.pdf

Stephanie Custis (yes, Mark's wife)

Thanks, Dave

GREAT article! I saved it and will use it as a sales tool for tankless. Oh, and we also have a Rinnai providing heat for both DHW and a radiant floor (family room/bathroom slab addition). We used a water-to-water heat exchanger to keep the systems separate. We might have specified a small mod con, but the owner had already purchased the Rinnai. System works just fine.

Thanks again.

"Opportunities are never lost, someone will take the ones you miss."

Dave Yates (GrandPAH)_2

dual use

Nice to see you posting! As for the women in whatever? Bear in mind that some of the first plumbers (Roman early plumbing) were women.

Robert Bean has this one on his web site regarding open vs. closed dual-use water heaters.

http://www.healthyheating.com/tools/Dave Yates H20 vs Boiler.pdf

Erich_3

More, Well let's See

Navien has no minimum flow, Rinnai has a minimum flow.

Navien "A" models have a built in circulator Rinnai does not.

Navien has a 98% efficiency Rinnai does not.

I have not seen a Navien overshoot the temperature. Show me some conclusive evidence or testing that establishes that fact.

Rinnai has a recall for 52,000 direct vent wall furnaces due to a carbon monoxide risk.

Rinnai is a quality Japanese manufacturer. They also make rice cookers.

KyungDong Navien Co., Ltd. is a leading quality Korean company with three factories. They do not make rice cookers.

Mark Eatherton

Great article Dave...

EXCELLENT!

ME

mark ransley

Navien 98%, what does one of those cost, that sounds like the most efficient made.

Erich_3

Call Navien

1-800-519-8794. They can help you with the model you need and any other information.

Stephanie Custis (yes, Mark's wife)

Navien

Mark,

Last time I checked the Navien wholesales at about $2000. Yikes! It does vent in PVC, so it it has low venting costs should you not be able to place it on an outside wall. Google it, however, and you will find many unhappy customers/installers.

"Opportunities are never lost, someone will take the ones you miss."

Jack_42

Navien does

some things quite well. i am not saying that they are a bad piece of equipment. They are to be commended for the eff and the zero min flow.

I do not consider the internal recirc pump to be a feature. Some do, but it limits your flexibility in dealing with individual system requirements.

As to the temperature spike issue, take the time to remove the cover and run the test on them and I believe you will see it for yourself.

We are both supporters of tankless water heaters. You for Navien and I for Rinnai. Over 18yrs, they have earned that from me. Yes, there is a recall of 52,000 dv wall furnaces (www.wallfurnacerecall.com, for those not familiar with it). I have about 80% of them in my area. The recall has gone well, but much remains to be done in finding and repairing the remaining units. It is unfortunate not only for Rinnai but the entire industry, when such a thing happens. To their credit, they identified the problem and took it to the CPSC for assistance in putting an effective program together to repair these units. The parts kit is well designed as is the solution itself. As well, they have paid a reasonable (no it is never enough) rate, $95 per repair (about 30-45 min work) and travel if beyond a certain point. I am indebted to our good dealers who recognized the gravity of the problem and went out and got the work done. Of the many thousands done I will say that our dealers were generally pleased with the way it has been handled. Rinnai has been a great line for them for many years and they worked hard to protect the public, themselves, us and the market. For the record, sales of the dv wall furnaces hit record numbers in '08, in spite of the fact that we could not sell the units until the first of March, '08.

Kyungdong is a giant, diversified manufacturer. they are a powerhouse. they designed and sold us the Quietside boiler, so their product support is legendary.

Rinnai makes a wide range of kitchen appliances. I have a two burner cooktop with a small 5500 btu broiler. If you camp or cook outside it is just a fantastic product. I was in a Korean restaurant in town a couple weeks ago and they had Rinnai gas barbeque grills built into the tables. When I told the chef I worked with Rinnai he told me they are famous in Korea, as well as around the world. He was very happy to praise their products.

Their rice cookers are so cool it is incredible. Rinnai developed a rice cooker which senses, through a proprietary switch, when the water has boiled off. It then shuts off the burner so your rice is always, as in every time, properly done. I am in hopes that Rinnai brings more of their products to the US. I'd love to sell them. It is the number one brand of rice cookers in Korea

I think we can go around and around on this. I would suggest that the market and competition is the tank manufs. Collectively, tankless represents 4% of the overall market. There remains plenty of room for both companies to grow...and they will!

Jack_42

Sure Shane

Run the checks I suggested and give me a call.

Erich_3

Great Companies

Jack, you are correct. They are both great companies. Through the years I have found that Japanese companies have always exhibited a method and a will to constantly upgrade their products. Look at the first Honda cars that came to the US. They were not much of a car but they quickly learned and became a dominant force in the Automotive industry. Look at Toyota. They have even gone into NASCAR racing. Look at all the Japanese electronic firms. Japan is the number two manufacturing country in the world. What is really remarkable is that they are a small island nation with few natural resources. With a Japanese company you can be sure that if there is a defect, they will correct it and make it better than it ever was. In my house, I have a Japanese on demand water heater. Whenever I look at it I am amazed at how little fuel it uses and how I can take a two hour shower without the temperature changing.

Terry Larsell

I went to the local Navian install class and I have a willing beta tester friend of mine to try it out on. It looks nice and the price is very competitive. The recirc and pvc venting make it hard to ignore. I hope it stands the test of time.

Terry