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Tankless Water Systems

I am researching before purchasing; a tankless water system. Does anyone have any input? Which is the best (IE: Paloma from Home Depot)? Which has the best ratings? Are they all they're cracked up to be? We have a regular water heater currently, and we are on propane. I am trying to reduce propane usage and bill amount. I ultimately want to go as green as possible...efficeincy. Thanks so much.

Re: Tankless Water Systems

First, what kind of heating system do you have now???

If you happen to have hot water heat you would be much better off with an indirect hot water heater, that doesn't burn any fuel on its own.

The biggest knock against standard propane/gas HWH is there is a lot of STANDBY loss, since 30-40 gallons of heated water sits there in a storage tank for hours or overnight without being used.

There's some truth to this, but mfgrs have greatly improved the insulation on these tanks now so that the standby loss is much less than before.

Sites like Water Heater Rescue still contend that a standard 30 gal or 40 gal propane/gas HWH still outperforms a tankless hwh in fuel savings, especially with families with more than 2 people, click onto "choosing a water heater" at the site.

I've heard & read a lot of both good & bad things over the years on this forum and elsewhere about tankless HWH.

They became very popular in Japan & other parts of Asia and many Japanese mfgrs still dominate the market, China now entering mkt.

Some of these mfgrs have been known to go out of business, leaving the homeowner & any warranty high & dry.

Hot water usage is quite different in most of Asia, than in the U.S.---we are more used to "all the hot water we need, when we need it" in the U.S., this is not the case in other parts of the world.

Other factors are size of family, number of baths, hot tubs, jacuzzis, clothes washing, dishwashing, any teen & pre-teen girls in the family who take a lot of showers, etc.

If the family is small, one or 2 people, you may be a good candidate for tankless.

Natural gas is best, propane second, an electric tankless will cost a fortune.

Sometimes the gas supply main is too small so they have to install a bigger gas main.

Tankless water heaters are not liked by some engineers because they require a lot of heating btu's/hr, & usually deliver a few gallons/minute then the water turns lukewarm; check out the PM mag site below for the engineers' pov; you may have to register at the site, but it's free; enter "tankless hot water" in the search box to read the articles.

Very large systems are required for larger families, & the install can be very expensive.

Be aware that the technology between wall-hung condensing boilers and wall-hung tankless HWH is merging---don't overlook the condensing boiler option.

The technology on these systems seems to be improving, & they are definitely more popular now in the U.S.

There is usually a federal or mfgr rebate to the homeowner for having one installed, but you could go thru 5-8 standard propane HWH before you pay off the investment in a tankless; then you would have to get used to the different way they operate.

Try to get a plumbing contractor in your area who has installed several & see if he/she & the homeowner will allow you to check out the installed system in a home that he/she did.

Also ask around to neighbors, friends & relatives to see if they have one installed, that you can check out before you plunk down thousands for an install.

Some of the popular mfgrs are Paloma Pak, Takagi T-k2, Bosch Aquastar, Rheem, Bosch, Steibel, Bradford White & many others.


Re: Tankless Water Systems

I think tankless water heaters are the way to go. However, I do not think going with Home Depot is the way to go (50/50 there). Palmona is a good brand but I like and have used and have installed Rheem, Takagi, Rinnai. Go to a local plumbing supply store that sells them and ask for a referal.

This is sizing and suggestions: 1-2 bth/4-5.5 gal 2-3 bth/5.5-7.4 gal 3 bth/7 gal. Propane (or Natural Gas) is better than Elec. Also, Rheem RTG-74 $850 5.5 gal+ Rheem RTG-53 $660 3.9-5.5 gal. Also go to http://www.tanklesswaters.com/ for info.

I really do belive for the extra $200-300 you will pay for the unit (over a replacement water heater) you will make up for in fuel costs. The only problem is people might take longer showers! Good luck. Process of elimination

Re: Tankless Water Systems

Thanks so much for the replies and great input. I appreciate your help.


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