OT Hot water heater question

texaswig

I was looking into it. And I would need to upgrade from 1/2" to 3/4" gas line. From what I've read I would barely recuperate the cost over the life time of the on demand over the regular gas heater from the upfront cost of the unit not counting the gas line change. I was manly looking at a on demand because it would take up less room in the laundry room. 

texaswig

Oh and the other thing I forgot is most all on demand units need power to work. So in a emergency no hot water. 

Eggcelsior

texaswig said:

Oh and the other thing I forgot is most all on demand units need power to work. So in a emergency no hot water. 

If your house is gas, it is likely that your stove is too. A match works just as well as the electronic ignition for that so boiling water isn't an issue. It's inconvenient, but hey, you're in the dark to begin with.

nolaegghead

We've had our Paloma on-demand unit for 10 years.  The only problem I've had with it was a failure of the control board.  The company over-night shipped a new board and offered to pay a plumber to install.  I just did it myself. 

It's nice to not run out of hot water, and we're low on space so the big tank is gone.

People think "instant" hot water and don't consider the time to heat the pipes delivering it to the faucet.  It's not any slower or faster than a tank, well, maybe a second or two slower.

The payoff is long but you don't run out of hot water.  I had to run a 3/4 gas line to hook it up.  I tapped into the 1 1/4" generator line.

We have a 100 Amp feed to our house (since we're gas, we don't need more).  That doesn't cut it for an electric on-demand.  Typically you'll need 120 A in three circuits.

Canugghead

@nolaegghead - our Paloma is about 9 years old, from the same generation as yours. Touch wood, it's still going strong, I have it hooked up to a UPS so it works during power outage, and hopefully protects the circuit board somewhat.  I had to jury-rig two free batteries, in series, from Kijiji to replace the oem battery.  

Should mine fail, since I'm in GWN, I'm not so sure if I can get such good customer service from the importer (assuming they're still in business!).  When did your unit fail and who did you contact?  Better to be prepared! 

nolaegghead

@Canugghead - I think ours failed right after our warranty expired.  I helped a friend of mine put the same unit in his house a year after I did mine and his had the same problem while in warranty. 

Turns out there's a defect in that product line and they extend the warranty due to that defect (with their discretion).   

I don't remember who we called....Paloma is Japanese but I believe Rheem is reselling for them now.  I think we called Rheem.

I seem to remember these units have an estimated life of 15 years.  If ours makes that without repair, I will build a gold statue of my tankless heater and erect it on a shrine.  We abuse ours (SWMBO always turns on hot water, even if she doesn't want to wait for it).

Canugghead

Thanks @nolaegghead - I have to keep reminding my folks not to turn on hot water for quick hand wash; also do you think not turning on full blast helps to reduce stress on the heat exchanger?

nolaegghead

@Canugghead My guess (and it is just that) is that turning it on full blast or cracking it doesn't make as much difference as just cycling it on and off.  When you turn it on, you're cycling the gas valve actuator.  There's a proportion valve that adjusts the gas to make the 120F or whatever you have it set at temp. That constantly adjusts.

The scale in the heat exchanger is greater if you have it blasting at its limit, but you can remove scale if you do the scale service (which I'm sad to say I've only done twice).

Our water isn't too bad here since it's from the Mississippi versus a well, we have moderate hardness. 

Canugghead

@nolaegghead you have pm!

jaydub58

I have had a gas-fired Rinnai for about 6 years.   In our house it takes about one minute for heated water to get from the heater to any tap in the house.  A bit longer than our old electric tank, but not by much.
Being retired, we are at our hideaway on the coast for a week 7-8 months each year.  This system sure beats paying our local utility (very expensive) to keep 50 gallons of water hot while we are away from home.
That plus the point of never running out of hot water makes it winner winner!
  

grege345

@jaydub58 natural gas or propane?

jaydub58

Natural gas.  Fortunately the street we live o contains a gas main.  As we were installing two other gas appliances (fireplace, cooktop), the gas company ran from the main into our home for free!