anyone using a Rannai tankless water heater?
 

i am looking into one. apparently is is one of the better brands of tankless out of japan. anyone using one? the other brand is tekagi. i think the tekagi can run hot water at a lower rate. damn this schit is confusing.

Look at Bosch. I hear those damn Germans are good at mechanical stuff...

There are charts that tell you exactly what size you'll need. You need to know your average incoming water temp, gph of your municipal system and anticipated usage (family size, bathroom/sink/laundry count, etc). You most likely will have to upgrade your electrical circuits/wiring to handle the load (assuming we're talking about an electric unit), as some of these units use double 80a breakers :eek:

Don't let the (inevitable) naysayers discourage you. Tankless is the way to go.

Plenty of info on the internet. If you take a little time, you'll get the hang of it. I wouldn't go for the electric unless you have a specific reason or want to upgrade your electrical service. Like Danny said, 160 amps of power is a real load to devote to one appliance. There are some things you should become aware of in researching these, for instance, is the brand you are considering serviceable in the field or not. There are a bunch of others, too much to list here.

Vash,

I say one word. Takagi. Stay away from the Bosh units. Noritez (sp) is my next choice.

Tell me what you are doing. How many baths? body jets, tubs muti shower heads? How long is the run from the heater to the bath. If its too long you will wait for a long time for hot water, so you will need a recirc. pump and additional piping. and get a thermo switch so the pump will turn on and off when it senses a certain temp. don't let the plumming guys sell you a pump that has a timer temp switch in one unit. That **** doesn't work. Ask me how I know. Also offdifferent units require different size gas line and some may need greater pressure. If you mount it outside, then all is fine. If its inside, you need specific SS vent lines.

I have a Takagi TM1 commerical unit at my house and all my client's as well. I think they are the best money can buy. Tech service is great. You need to find a good plummer who know what each specific heater needs and be very specific on that if not it will not function property. Plummers do not like to read. That's my job. Good luck.

Rannai used some Chinese parts last time I heard. Why do you think Takagi is so much more then anybody else's? because its the Lexus of h2o heater.

When we looked a few (3) years ago, the tankless units still were not recommended for a family of 4, especially with 2 showers going at the same time every AM, as well as a dishwasher, washing machine, etc... We got a 50gal GE water hreater and that thing can barely keep up. They seem to be pushing the tankless units at the home improvement shows. If I recall, you have to use stainless steel (not PVC) to exhaust the tankless units, too.

lolo, here is something I've thinking of exporting for the past 13 years.
size to price was a major issue at the time.

Different makers but I haven't heard of takagi or rannai yet ... however, rinnai is a pretty major brand for heaters, stoves, and tankless units.

I've been on the tankless units for the past 15 years ... no choice in the matter actually.

There are various sizes and can do heating oil, LPG or natural gas. I've been on a LPG for the past 10 years.

There are even ones that will recirculate your bath water to keep it nice and warm for whenever you want to take the next bath (warning ... Japanese don't use soap/bubbles in the bath tub)

My crappy unit holds up really well for oodles of showers in a row.

Problem with my dinky unit is that 2 showers just won't cut it. Also, flushing is shocker. However, the temps are now electronically set and you don't really need to adjust those dam facuets to get the right temperature for your shower.

You do need a ventalition duct to run one in the house ... electric I'm not sure.

The nice thing about these things is that hot water is on demand. Versus a tank which goes cold and needs time to reheat the water.

Lag time from unit to faucet is not really that bad. Of course, shorter the distance the faster you heat up.

PVC probably won't work ... at least at the top of the unit. However, from there on out ... the heat is not that bad where it will melt anything. The blow off does sort of heat the area where the tank is located so you can dry towels pretty quick.

Don't need steel. You can get away with alloys possibly even aluminum.

Older models were located right over the kitchen sink with there own tap. Sort of weird in the beginning but after a while they grow on you. I've always hated being the last one in line for a tank shower. I always got screwed :rolleyes:


Now, of course, all this information is regarding to units I have used in Japan.


Anybody interested? I'm sure I can start digging around and possibly get em over to the states. I'm not sure what the difference is between US and Japanese natural gas is though ...

just got one after much looking and comparing. love it. don't bother with the remote controls though. and have it installed by a licensed rennai plumber.

Bosch does not have such a hot reputation when it comes to home appliances.

Just remember, if you lose electricty, you won't have any hot water. Probably not a big issue in CA, but in the midwest it's something to consider. My in-laws in central KS have spent probably 2 weeks in the dark over the last year due to tornados and ice storms. Even in the dark, it feels good to take a hot shower.:)

Bosch makes a great product. I try and infulence home owners to purchase the Bosch dishwashers. They are that good and quiet. Of course there are better out there. tankless heater isn't one of them. My plumber woun't install them. He knows there will be call backs.

I nearly bought a Bosch LPG tankless hot-water heater 3 years ago. I couldn't find a plumber willing to install it (and my wife forbids me from messing with natural gas).

The unit you mention is too small. Look at the float rate and the water pressure coming into the house. The pipes might be old and don't have enough float. Many of our clients have muti shower heads, body jets and big tubs, still run the dish washer and wash clothes at the same time. A big unit like the TM1 will do the trick. I have that very same set up at my house. God only knows my wife take the longest shower when our kids are over at my parents. She sits on the freaking bench in there. The temp doesn't drop at all after 1/2 hour of running the shower. Sometimes, we install 2 units in each corner of the house so the run isn't too long with a recirc. pump. Inorder for that to work correctly, I always suggest changing out some of the incoming water pipes if it hasn't been change in 50 years. Many people think that I am trying to rip them off and sell them something they don't need. My job as a contractor is to educate my client so they will have years of trouble free kitchens and baths. If they disagree, and still expect it to work at a 100%, then we will not take the job. I refuse to do *****y work. It like putting a turbo charger in a SC motor with over 250,000 miles on it and expect it to be last for years to come. 70% of our work is design and build custom kitchens and baths. We have never have any problems with these units so far.

look 171 - what would you recommend for a household with 2 people. Possible use of washing machine or dishwasher at same time. But unlikely to be running dishwasher, washing machine and showers at same time. So lets say running 2 showers and washing machine.

Really not sure the actual pressure of my water, but i live in a new developement with a decent water pressure.

Thanks
Matt

It really depends on the total amount of continous flow of water at the outlets. For example, how many shower head are going to be on at the same time, don't forget to include toilet and slight use of the faucet in the kitchen. Do you have muti. shower heads? All shower head are rated at 1.5 gpm. Unless you take the restrictor out. It like removing the cat. on your 911. Just add the total. The washers are not a big deal. They are draw water for a short period of time like 3-4 minutes. It your showers and filling the tube that will tax the system. I don't know if I have that info on hand right now, I'll check my truck. If not I'll find out for you within the hour. I am just screwing around here this morning waiting for my AC guy to show up.

Try to install a regulator to control the pressure of the incoming water. If you are up on the hill, water pressure is usually greater. You need to regulator that. I like 65lbs of pressure. An expandsion tank maybe necessary. Check your local building code.

Jeff

talked to the plumber. he sells both the tegaki and the rannai. he feels the rannai is the better product. damn. he says both are very similar in pricing. most of the units, my in-law have in taiwan are either. too bad i just cant call them up and ask. i dont speak mandarin anyways. he specd out the R53e for my house. it is a tiny shack.

thanks for all the really great advice. my old roommate bought the bosch unit from homedepot. it SUCKS! lukewarm, tepid water if more than one person is using it. and you get zero hot water if you trickle it out, like during a shave. full tilt boogie or nothing.

i am sold. my wife uses alot of hot water. i take spit showers, and cold ones at that in the summer time. it is really all about HER.

look. thanks!

i am having my house re-piped 100% at the same time. nice having a plumber (i am assuming?) on the bbs!

Try the TK3 unit.

Thanks

Timely thread. I have to replace a new useless electric 175 liter tank. I've been looking at tankless. Thanks for the Bosch avoidance btw guys.

Jeff

The gas & water are all close enough to allow for outside or inside use. In a colder climate (Toronto, Ontario Canada), is outdoor an option or will it just cost more since it will be in freezing temps for 4 months or so?

Eyeballing the T-K3 In or Out.

4 people getting reduced to 2 soon (I fervently hope). One shower. Low municipal pressure (they're working on it).

Thanks

Ian