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General discussion

Tankless water heaters

Aug 16, 2018 3:32PM PDT

I just replaced my Tankless with a real water heater. I wasted more water waiting for the water to get hot than savings on my utility bill. Once the water was hot at the heater it had to travel through the pipes and push out all of the clod water. I was wasting 6 to 8 gallons of water per day. Also you have to have them flushed yearly, they may say every two years but that is not enough and it cost about $250 for a plumber to come out and do that. I did not and do not see the savings, actually my gas bill has gone down. It is just HYPE.

Discussion is locked

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Here in the UK...
Aug 16, 2018 3:46PM PDT

we call them combi boilers. I agree there is a certain amount of waste water, but where I live I'm not on a water meter. But the radiators get hot in seconds instead of waiting for the tank boiler to heat up.
Dafydd.

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Here in southern California.
Aug 16, 2018 4:28PM PDT

There is a gallon or two in the pipes so when the drought was at its peak I had a bucket to catch some water to take to the garden. This isn't going to hit as many gallons as you but for hot tap water we just put that on the burner rather than wait for the tap to get hot in the kitchen.

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We have a three bedroom, two bath home.
Aug 16, 2018 8:14PM PDT

The master br and bath, and the kitchen, are next to the water heater, which is in the garage. The other two br and the second bath are at the other end of the open floor plan. It bothers me, especially in dry NM, to wait for the water to heat up, so I usually do the ablutions [Dafydd can translate] with cold. [The girl got the nice bath when we moved in; my son and I got the little one. Happy ]
My solution will be to install a small tank under the sink. Just enough for a shower. Fast response, very little water heated when not in use.
One problem is that the budget says DIY which I can do, but not by running a gas line. Electric is more expensive for heating anything, but the payback s/b OK.

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I'd think this type might be best
Aug 17, 2018 2:03AM PDT

if installed in newly constructed homes with proper plumbing. I can imagine that older homes with copper plumbing...especially in colder climates...will fare worse with tankless systems. The volume of water of water already in 1/2 inch copper might be part of the problem and longer runs will make it worse. I could imagine that a better solution would be to run smaller ID individual lines from a manifold system to each hot water outlet. As well, using PEX might help as well. My wife and I rented a place for a week in Boone, NC a few years back. We didn't know it had a tankless system and I almost called the rental office the first time I tried to take a shower as I thought the water heater was malfunctioning. It took several minutes to make the water stream comfortable. This was an older home in a Blue Ridge Mountain area and the time was September. it was cool but not uncomfortable but I can imagine that, in Winter, getting hot water would take much longer.

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Tank type
Aug 18, 2018 6:33AM PDT

Water heaters are all over the map efficiency wise.

CR did an article about them.

They took 12 different water heaters and put them in the same room.

All the heaters were the same capacity and set to the same temp.

They filled them and let them heat then they monitored how often they cycled in a 24 hour period with no water draw.

The worst units cycled hourly.....expensive to run often cheaper to buy.

The unit I bought cycled twice.

Then you have the 2 person family that has an 80 gal unit....expensive to run.