We have a Bosch gas one that is probably 7 or 8 years old (I would have to look up when we bought it). It's never been hot hot in the winter unless we run the faucet with the shower, but we figured it was because we plumbed it into old piping and the fittings are not quite to spec.
However, this last year it's gotten really bad...no hot water unless the faucet is running full force. Obviously somewhere this is a buildup in the system; the water flows in at about 2 1/2 gallons per minute.
We can't seem to get parts or ways to test these much; we are at the point of just selling it for cheap and going back to a standard water heater. Don't want to pay someone to come in and tell us entire plumbing has to be redone (we are thinking of selling the house in a few years...it's suddenly too big now my kids are off on their own).
Anyone have any history with these breaking down after so many years? We find mixed reviews with them...seems some people have problems, others do not.
That it gets hot when the water flow is increased .... Sounds like the controls are limiting the water temp. Get a manual to see the adjustments if any. I doubt the plumbing limiting unless it can't flow enough water.
If the shower pipes are galvanized, then they shrink inside the pipes with corrosion build up. For any other kind of pipes I would suspect something in the shower control.
Try googling the problem, and see if you find a message board of plumbing problems. It's amazing what's out there from consumers and professionals about all types of home repair problems. I bet the area below is the solution, and it's low water flow.
I found this on line: Low water flow = no hot water. If there isn’t enough hot water flow, a tankless water heater just won’t turn on. One person even commented that they had to turn on the hot water faucet at their bathroom sink and leave it on the entire time they took a shower, or they couldn’t get hot water. For instance, Rinnai tankless water heaters need at least .6 gallons per minute, Bosch units need .65 gallons per minute, and Rheem at least .4 gallons per minute of hot water flow to kick on.
We have horribly hard water. We get ours serviced every year to be sure there is no build up of material in the system. Basically they flush it with vinegar for 20-30 minutes and do a visual check on some different issues.
We had a small problem with the hot water cutting out during showers. But it would come back within 10-30 seconds. I had the guy come out and he adjusted the computer for an extended exhaust pipe as he said this can sometimes be an issue. They are designed for a short exhaust pipe.
We have a Rinnai and its gas. The installer said the electric ones were not as good as the gas.
I can wash a load of clothes, have the dishwasher going and still take a shower. I love mine.
I looked into getting one a couple of years ago when I moved into a tiny house. My reasoning was that if I got a tankless system, I could convert the closet where the water heater resides into a desperately needed pantry. The husband of a friend works for a company that installs tankless systems and he said not just no but h*ll no, don't do it.
He said that in his experience, they are maintenance nightmares and have to be replaced much more frequently than a standard water heater.
Yep, I looked into one and decided against it because of maintenance issues. When I looked into it, I was told by the dealer that when going with tankless, you have to turn the hot water on FULL at all times to ensure that the tank triggers and has the appropriate flow to break up any sediment that might collect in the unit. If you haven't been doing this, it may have caused you problems. Personally, I'd look into going with a high end tank unit if you wind up needing replacement. They tend to be cheaper in the long run.
I can't help this problem, except to ditto a previous poster and see what Google can find for you.
We had a Paloma gas on demand hot water heater in a previous house, and it was AWESOME. I've always wanted another one, but the timing just hasn't been right.
We have a gas one in our lab (which is currently being used for mixing 40 calf bottles a day), and the cheap eBay (Chinese made) one we have in there right now is very finicky to get the water hot enough. I probably wouldn't buy one of those again, but the Paloma was in a whole different league.
I grew up with one of those gas on demand heaters.
It was hung in the bathroom, right on the corner, over the toilet bowl.
When someone somewhere would turn the hot water on, the thing would come on with a bit whoooosh and rattle along.
Too bad if you were using the toilet right at that time.
I don't think anyone ever got over jumping from that awful noise right over you, while you were trying to, well, whatever.
Oh, so it wasn't just me and my crazy rental house! My on demand hot water heater was great until you turned on a little cold water to temper the boiling hot water. Then it went completely cold! Waaa! Not fun in the shower, especially in the winter.
My thoughts - good in theory, suck in real life. I really did think it was installation issues at the rental house. Maybe not???
I put the handheld shower heads in all of the bathrooms. It is wonderful for cleaning the shower, or dog washing. The best feature is they're adjustable and it's the only way to get good water pressure. The regular low flow shower head so weak it's ridiculous.
Thanks, all...I'm going to remove the restrictor tonight once I figure out how (I know, Google)...and we have googled this to death. I just had someone tell me when they researched getting one, they were told to keep a standard gas one in line with it, turned off, so if the tankless failed, you would still have water. That's insane. Those of you who are happy with them..how old are yours? I wonder if there's sediment buildup in the coils...
We also have a Paloma tankless heater, gas type. Husband got the one-size-up, from family recommended model so it could manage having enough hot water for demand of several faucets at once. Does take a little time to get hot water upstairs from the basement, but it is good hot water, you don't lose heat erratically. I love the heater, never run out of warmwater washing 4-5 horses with the hose or doing laundry in the massive quantities I had/have with farm children and farm living.
We have had the heater at least 20 years, probably longer. Needed a new part once, which husband changed after ordering it from a Paloma dealer. The Paloma heater was not cheap, but has been a huge money saver with only heating the water we need. No worries about heater rusting out or getting a leak to flood the basement like tank heaters can do.
We put in a water softener system because we have such hard water you can chew it! The Softener seems to manage keeping the minerals out of the heater pretty well. The part that needed replacement was not mineralized, just worn out. I think it was the nozzle for the gas flame, not a water part at all.
I would buy another Paloma tankless heater again in a heartbeat. Excellent product for us, recommended to us by one of my old bosses who also had them in two houses way back.