BajaNomad - HOT WATER ON DEMAND UNITS

HOT WATER ON DEMAND UNITS

longlegsinlapaz - 2-12-2007 at 09:47 AM

I did a search & found a few comments on hot water on demand units from mid-2006. Does anyone have any follow-up information? I've done some research on-line, but realize manufacturers can & do hype their units & make it sound like the best on the market. I'm interested in some personal experiences...the pros & cons & lessons-learned. Ideally I'd want it inside the bano/laundry area, which would mean it would be 35' from the kitchen & dishwasher. Close enough? Too far? I'm curious as to why most of the manufactures talk about distance to hot water heater, even in new construction scenarios. In my mind, this unit would be in lieu of a hot water heater...flaw in my thought processes?? I'll have a water pressure holding tank & would like to eliminate any need for a conventional hot water heater & the LP it takes to keep the water hot 24-hours a day. The pilotlight-free unit sounded best until I read someone's comment about that makes it harder to diagnose problems! And here I was hoping that these would be problem/maintenance-free! :lol:

Pros? Cons? Lessons-learned? Warnings?

Recomendations? (and NO! Foregoing hot water all together ISN'T a feasible option!) :lol:

wiltonh - 2-12-2007 at 01:08 PM

The on demand hot water unit that we saw in Costa Rica was mounted just behind the shower head. It worked ok but it was scary looking up at the shower head and seeing 220 volt AC wires coming out of the wall and extending down very near the shower head.

--Wilton

Taco de Baja - 2-12-2007 at 01:25 PM

They only work ok. They have positives and negatives.

Positive: unlimited hot water.
Positive: save energy, only heat what you need.

Negative: High startup cost
BIG Negative (that they bury in the fine print): We had a "household" sized unit, but you could only have one hot water faucet on at a time....If you were taking a shower and someone turned on hot water in the kitchen or another bathroom, you would lose all hot water to the shower. Don't even think of taking a shower while the washing machine was on

.... They make larger units that can handle two sources at the same time, but they cost a whole heck of a lot more.
Negative: you have to install a 5-6" diameter, double walled exhaust vent in your roof to handle the extra BTU's.
Negetive The “pilot light free” one we had operated by 2 D-cell batteries. In the beginning they would last around 9 months. Then they were gone by 1 month (they still tested above 1 volt each…But the unit would not spark). I finally had to hot wire in a plug in transformer to the battery terminals, that produced a constant 3 volts. In addition if the flow of water was, too low, the pizio-electric spark would not kick in, and there would be no hot water

[Edited on 2-12-2007 by Taco de Baja]

movinguy - 2-12-2007 at 01:58 PM

"In addition if the flow of water was, too low, the pizio-electric spark would not kick in, and there would be no hot water."

That is correct - I stayed somewhere recently where I had to leave the sink faucet on to get the shower to heat. Not exactly a prudent use of water in a place like Baja . . .

El Jefe - 2-12-2007 at 02:13 PM

No, no, no, don't use one! We go two high end Bosch units, one for each end of the house. We could never get a good hot shower with them. The water would get hot after running about five gallons and as soon as you turned it down a bit it would go stone cold.

The poblem is with the flow rate, pressure etc. During use pressure tanks vary in pressure from about 20 to 45 psi. At the highest pressure the heater worked almost, but woe be to the user who tried to take a shower when the pressure was lower. I would hear profanities from the bahroom as my dear wife tried in vain to take a comfortable shower. Not condusive to cuddling on a cool winter night let me tell you!

Needless to say, I changed out to a regular old 30 gallon tank type heater and all is good with the world. I expect to change out the guest bath side soon.

If you do decide to get a tankless heater, I've got a couple in perfect condition I will sell to you cheap.

Good luck with your project. tom

El Jefe - 2-12-2007 at 02:15 PM

Oh ya, my neighbor replaced his thankless water heater too. Now all is good in the hood!

Capt. George - 2-12-2007 at 02:53 PM

does this mean I will have "dirty" neighbors in La Paz???

Steve in Oro Valley - 2-12-2007 at 03:03 PM

I installed an CEC POWERSTAR electric tankless water heater which utilized two (2) 220v lines and has worked great in my mothers casita for 18 months . Some of these units use only one (1) 220v line and appear to be too minimal in hot water output

I sized it to provide instant hot water (50 degree rise in temp) for her shower and bathroom sink. Hot water comes in about 4 seconds and lasts. She uses the water source one at a time, never simultaneously....It is mounted under sink against the wall inside the vanity. Our water in the ground here in Oro Valley varies about 60 degrees in winter and 80 degrees in the summer. No complaints from grammy yet.....

I do not notice any extra cost in the electric bill...

I did not and would not use a gas powered unit for this small addition as I did not want to install a vent and worry about malfunction and pilot light problems....

The cost is in running separate two 220v lines needed to provide the required heat. The Powerstar unit we used cost $400 plus and also of course the wires and electrician are extra....

Steve in Oro Valley

shari - 2-12-2007 at 05:26 PM

For years we had a very neat little unit only cost us $40 and it's a shower head that has a coil in it and heats the water as it comes through the shower head. It worked great and our electric bill was around $15 a month so doesnt use much power, just the few minutes when you're showering. Most people have that type here and the only problem is you can get a shock when you touch the shower head. they are simple to install and you don't need copper or cpvc pipe, just regular pvc. Most hardware stores have em.

David K - 2-12-2007 at 05:31 PM

Getting a shock when taking a shower is NOT a good thing Shari... :wow:

Oso - 2-12-2007 at 06:05 PM

You mean one of these?

redneckWH.jpg - 23kB

Oso - 2-12-2007 at 06:16 PM

Actually, we had an on demand water heater for showers in Cuajimalpa, a small village in the D.F. about 40 years ago.

First it would demand that we use a handpump to fill the tinaco upstairs on the azotea, so we could have a gravity flow.

Then it demanded that we chop some firewood and kindling.

Then it demanded that we light a fire under the tank in the bathroom.

Then it demanded that we wait half an hour for the water to heat up.

Then it demanded that we shower together (well that wasn't such a demand) as quickly as possible before the hot water ran out.

Capt. George - 2-13-2007 at 02:21 AM

getting shocked in the shower is a good thing for depression! I like it much better then those wires they keep attaching to my head!

maybe after all those earthquakes, ya don't even feel a little electric shock now and then??

gotta get two of those!

Bob and Susan - 2-13-2007 at 06:08 AM

Here is one of those Hot Water Shower Heads
They take A LOT of electricity!!!
25 amps
2750 watts
$50

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=11007...

They are used a lot for washing horses when it’s cold.
People sure love those horses.

I am with David though…
water + electricity = DANGER!!! :light:

Bob and Susan - 2-13-2007 at 06:11 AM

We have a BIG tankless unit for the garage…
Here is my source…nice people from Flordia…
http://excelamerica.com/

Washer works GREAT!!!
NO problems :saint:

The BIG unit was TOO hot for just a shower so we’re using smaller units for each casita.

You do HAVE to have a pressurized water supply…ours is 50 lbs
I’ll have one for each shower.

The cold water does go thru the unit and comes out HOT!!!
Unlimited supply

In our case we’re trying to cut down on propane usage.

Remember... when you have a regular hot water heater you’re heating water ALL day weather you’re using it or not.
BURNING propane!!! :fire:

We’ve noticed...you do have to leave the water on to get an even flow of hot water.
No turning the water ON AND OFF to conserve water.

I think if I had electricity, I’d go with a regular electric hot water tank and pay the bill but…

when you live in a place with no water, no electricity, no telephone, no services…
You just suffer… :lol:

Capt. George - 2-13-2007 at 07:51 AM

Save Water - Stay Dirty

PU

prt328 - 2-13-2007 at 08:00 AM

Sounds like we have a similar setup. I put in a 16,000L unit (whole house) from Home Depot. There were issues at first, but it seems to be settling down. Water pressure to the tank had to be increased to 45 lbs to get water to the far end of the house. I had to remove the flow restrictors from the shower heads as the unit need to see a drop in pressure to fire. Haven't had it long enough to know the battery life but I keep 2 D cells nearby (it only uses 1). Water is scalding hot WHEN it gets there - it takes 2-3 minutes to reach the far end (40? feet) of the house.
I kept a small "old fashioned" water heater next to the tankless "just in case" and have it plumbed in parallel with valves. The pilot is lit only if/when I need it.

Hope this helps.

Bob and Susan - 2-13-2007 at 11:10 AM

i think this is the best advice yet

Capt. George - 2-13-2007 at 11:36 AM

I beg to differ.

staying dirty still wins.

longlegsinlapaz - 2-13-2007 at 03:17 PM

I was hoping for more positive experiences/information, but I guess that's why I asked in the first place!!! Looks like Steve in Oro Valley is the only success story! Capt. George, I refuse to wash dishes & laundry in the pool! :no:

Not being a techie-nerd, I guess I'll be sticking to the good old standby gas water heater! At least I know how to make it work & historically they've been relatively trouble-free for me! It's really too bad that conservation can't be simplified! Thanks for all the input everyone....well, maybe except for Capt. George! :biggrin:

Capt. George - 2-13-2007 at 05:26 PM

well, well I gonna be your new neighbor....

there goes the neighborhood... but I'm a sport.

you can do your dishes and laundry in my pool, while I'm in it!

oladulce - 2-17-2007 at 04:16 PM

The water heating set up that worked great at our old place for showers, with below-ground plastic tinacos for water storage, was an American Standard 12 gal. RV propane heater with the highest btu's. That was the greatest set up- only took about 5 min. to heat up and got the water hotter than you needed and the temp remained consistent when using a water saving on/off button on the shower head. 4 people could easily shower ( not simultaneously) with only a few minutes between for reheating. The tank was small enough that it didn't waste a lot of gas and we'd only turn it on right before showering because it worked so fast.

We installed a similar set-up in the recently completed guest casita in Punta Pequeña and just returned from our first winter visit. Unfortunately, American Standard no longer makes that rocket-blaster RV water heater so I got a different RV brand, and now our water is stored in a below-ground concrete cisterna that sits in a lava bed and felt like a cave in Iceland inside.

The starting temp for the water was v-v-v-ery f-f-f-rrrio and combined with the less effective water heater, provided less than satisfactory results for winter showering. Warm, but not hot enough for me unless I shower in my wetsuit. Definitely going to need to rethink this set-up.

BajaBruno - 2-18-2007 at 10:20 AM

I have an amusing story about these things. I used one at a local's house in Antigua, Guatemala, and it worked great. Small and primitive, but made hot water for the shower for hours. That's the good story.

The other story was when the Nat'l Park Service maintenance crew thought it would be a good idea to install one for the shower in our little gym at Petrified Forest N.P., Arizona. Well, as Steve in Oro Valley points out, these things are rated not for temperature, but for degrees above ambient temp, which means that they will raise the temp of the incoming water a certain number of degrees (not a problem for longlegsinlapaz), but when it is 5 degrees F outside, you get a very chilly shower.

The real problem, however, was that the NPS boys mounted it in the bathroom closet with louvered doors and had the propane adjustment screwed up, or maybe it had jets for natural gas or something. I just know that as I was showering I got this overpowering urge to go to sleep. Fortunately, I figured out that I needed to get out of there before I went unconscious, and I stumbled out into the gym, wet and naked (which made for some chuckles after the scare was over), and collapsed with carbon monoxide poisoning. Fresh air cured the problem and the boys went back to a tank heater.
I still like the concept of these heaters, but there are issues.

longlegsinlapaz - 2-18-2007 at 03:39 PM

Let's see if I got the salient points out of all these posts; my options are:

- Boil

- Freeze

- Potential electrocution

- Potential carbon Monoxide poisoning

- Stop showering

- Buy paper plates

- Buy wear 'n toss clothing/sheets/towels

or....................

Stick with the old tried & true technology of a conventional gas water heater & bite the bullet on LP costs by heating water 24-hours a day.

or.................... :light:

Possibly go electric & add an in-line timer that turns it on for a couple hours in the AM & again in the PM.

or.................... Captain George, please advise hours & location of your Pool Laundromat/dishwashing facilities! :lol:

I'm also curious how often you plan on doing a full water change for sanitation related reasons.

longlegsinlapaz - 2-18-2007 at 09:52 PM

Larry....Uhhhhhh....because you been holding out on me??? :lol:

Solar as in a black tinaco on the roof? Or solar as in solar panels to generate electricity for an electric water heater? The latter might be easier to control water temps a little more reliably!

BigWooo - 2-19-2007 at 07:07 AM

There are actual solar water heaters but they don't seem very easy to install yourself and are a bit pricey.

Here is an article about them.

http://www.ucsusa.org/clean_energy/renewable_energy_basics/s...

water heaters

jimgrms - 2-19-2007 at 09:11 AM

Quote:

Originally posted by longlegsinlapaz
Let's see if I got the salient points out of all these posts; my options are:

- Boil