Water heaters

What does the hive recommend?

Yesterday, I got called home from work with one of the water heaters spilling out from the top. OK. This one is gone. (yes, I have two thanks to previous owners).

House is setup for natural gas. remaining unit vents into the chimney, the dead one was vented through the side of the house.

Does the 6, 9, 12 year really make a difference when in a climate controlled basement?

Does it matter where it vents?

Also, for a family of 6, does a tankless unit make sense?

Another alternative with its own pro's and cons--

After putting up with a power vented unit on propane that would foul and fail to light unless you cleaned the thermocouple on it every couple of months (no hot water=SWBO very angry), we went with an air sourced heat pump driven water heater.

Our local electrical utility was heavily rebating the units and installation, and, at least at the time, they also qualified for a tax rebate.

If you're water heater is located somewhere you currently need to run a dehumidifier, you can elimate the dehumidifier-- though you should check every once in a while to make sure the drain is clear.

Downside is that it does make fan noise, and if you don't have enough amps available to run an electric water heater, that's going to add to the install cost.

And of course, the utility did subsidize the install because they get to sell more kW-hours...

I only know electric water heaters, and they are sort of the same as entry level riding mowers = they are all junk. Just plan on replacing every 8-10 years.

And when you replace one you can weld a pipe down the center of the old tank, fill it full of concrete, and have a nice lawn roller.

Karacticus wrote: Another alternative with its own pro's and cons-- After putting up with a power vented unit on propane that would foul and fail to light unless you cleaned the thermocouple on it every couple of months (no hot water=SWBO very angry), we went with an air sourced heat pump driven water heater. Our local electrical utility was heavily rebating the units and installation, and, at least at the time, they also qualified for a tax rebate. If you're water heater is located somewhere you currently need to run a dehumidifier, you can elimate the dehumidifier-- though you should check every once in a while to make sure the drain is clear. Downside is that it does make fan noise, and if you don't have enough amps available to run an electric water heater, that's going to add to the install cost. And of course, the utility did subsidize the install because they get to sell more kW-hours...

How is it working out for you? We installed a slightly used one last year bc it was too cheap not to, but I would like to go this route when this one goes.

Most of the tankless water heaters have a, as you would expect, maximum flow rate for a given temperature rise, but they also have a minimum flow rate for the unit to turn on the heating portion. With a unit sized large enough to run the inevitable two showers, dishwasher, laundry machine, and kitchen sink concurrent situation for a 6 person household, I don't know if it will turn on when the only call for hot water is a single lavatory (0.25 to 0.5 gpm).

If you have a circulation pump in your house, there might be a tankless heater that can have the minimum flow rate met by the pump and then only heats the water when it gets below a setpoint, but I haven't look into that yet, myself.

ddavidv wrote: I only know electric water heaters, and they are sort of the same as entry level riding mowers = they are all junk. Just plan on replacing every 8-10 years.

+1. The one in my house was starting to crap out and with it being almost 8-9 years old, it made more general and financial sense to just replace it. Brand new heater was installed next day. Parts for the old one would have taken a week or so to arrive due to the age of the heater.

92dxman wrote:

ddavidv wrote: I only know electric water heaters, and they are sort of the same as entry level riding mowers = they are all junk. Just plan on replacing every 8-10 years.

+1. The one in my house was starting to crap out and with it being almost 8-9 years old, it made more general and financial sense to just replace it. Brand new heater was installed next day. Parts for the old one would have taken a week or so to arrive due to the age of the heater.

So how long do you guys expect a gas heater to last?

I've always just assumed you could expect 8-10 years for one.

Family of 6 here. I had a bad experience with a small Bosch tankless under-sink unit(heating element didn't shut off & melted all the cpvc), so for our new place we went with an AO Smith power vent unit. It wasn't cheap($1400-shipped, IIRC), but it will essentially keep up with constand demand. Our pipes aren't insulated, and they're long runs, so we do get a bit of a temperature drop during the colder months after continuous use. Then again, I've never set it any hotter than the default setting. Seems to be cheap to operate too, but we also have a gas oven & 2 furnaces, so it's hard to say for sure.

The people saying all electric HWHs are junk are probably talking about resistance electric heaters, not air source heat pumps, am I correct? A heat pump unit is what you are more likely to encounter today and considerably more efficient than a resistive heater.

z31maniac wrote:

92dxman wrote:

ddavidv wrote: I only know electric water heaters, and they are sort of the same as entry level riding mowers = they are all junk. Just plan on replacing every 8-10 years.

+1. The one in my house was starting to crap out and with it being almost 8-9 years old, it made more general and financial sense to just replace it. Brand new heater was installed next day. Parts for the old one would have taken a week or so to arrive due to the age of the heater.

So how long do you guys expect a gas heater to last? I've always just assumed you could expect 8-10 years for one.

we have "hard" water and a softener - usually 5-7 years is it.

We've got a Rheem tankless for a couple years now. Maint free and works well, but at $1k for the unit, about 3 times equivalent traditional gas. We're never going to make up that difference, but I needed the power vent feature, and the traditional style with power vent were about the same cost, so I jumped.

nepa03focus wrote:

Karacticus wrote: Another alternative with its own pro's and cons-- After putting up with a power vented unit on propane that would foul and fail to light unless you cleaned the thermocouple on it every couple of months (no hot water=SWBO very angry), we went with an air sourced heat pump driven water heater. Our local electrical utility was heavily rebating the units and installation, and, at least at the time, they also qualified for a tax rebate. If you're water heater is located somewhere you currently need to run a dehumidifier, you can elimate the dehumidifier-- though you should check every once in a while to make sure the drain is clear. Downside is that it does make fan noise, and if you don't have enough amps available to run an electric water heater, that's going to add to the install cost. And of course, the utility did subsidize the install because they get to sell more kW-hours...

How is it working out for you? We installed a slightly used one last year bc it was too cheap not to, but I would like to go this route when this one goes.

So far so good, though our household is only two.

Impacted the electric bill enough (relative to propane) that I'm not sure I would recommend it on a cost basis unless you needed the dehumidifier. Has been much more reliable though.

I installed a heat pump water heater about a year ago and we like it so far. I was replacing an oil fired water heater, so doing the math of kWh versus gallons of oil + annual service contract, it was a no-brainer. The kickback on taxes and from the utility co was gravy. That said, the payback period might not be as attractive when doing kWh versus gas so do your own calculations.

We did a self-install and it was very easy. You just need an extra set of hands to help move it around. We keep it set on hybrid mode, where it uses the heat pump until demand is high enough to need the electric elements enabled. They also have a high-demand mode that moves the switchover point which is handy with company in the house.

Our natural gas water heater was installed in 1989. Still works great!

How do you heat the house?

If you have forced hot water it may be worth looking at indirect tanks. You get the benefit of 40-60 gallons of stored hot water,and whatever btu's the boiler is rated for (probably 100K or more) to heat the water.

As mentioned, tankless units can be a problem with low flow usage like sinks, dishwasher, and high efficiency clothes washers.

Everything in the house is natural gas. Furnace is forced air.

trucke wrote: Our natural gas water heater was installed in 1989. Still works great!

Mine was installed in 1991 and works fine. We've got hard water, too. Hard enough to leave rust stains if the sprinkler is allowed to hit the house.

If you have natural gas, then stick with natural gas. Short of going solar, it's your cheapest current option. Regular vented thru the chimney gas water heaters are around 62% efficient. I say 62 because that is where the energy star ratings kick in. Normal power vented water heater have the fan on the top and are basically the same water heater except they add air to the exhaust to cool it down, so that it can be vented with PVC. They cost about twice as much as a regular vented WH. High efficiency on demand water heaters, such as the Bosche, Rannai, etc, are more in the 95% and up efficiency range. They cost 3 to 4 times what a normal water heater costs to buy and much more to install. The biggest drawback to retrofitting them on an older house is gas pipe sizing. They draw 200,000 or more BTUs when they fire. The small pipe you have supplying your regular water heater is insufficient. In most cases you have to re gas pipe the whole house. My suggestion is cheap out and buy a regular one that vents back into the chimney, and expect to get 6 to 10 years out of it. Avoid doing a tank run off your boiler unless you have a high efficiency gas boiler, because a regular boiler will need to maintain temperature year round so it can make the domestic hot water.

z31maniac wrote:

92dxman wrote:

ddavidv wrote: I only know electric water heaters, and they are sort of the same as entry level riding mowers = they are all junk. Just plan on replacing every 8-10 years.

+1. The one in my house was starting to crap out and with it being almost 8-9 years old, it made more general and financial sense to just replace it. Brand new heater was installed next day. Parts for the old one would have taken a week or so to arrive due to the age of the heater.

So how long do you guys expect a gas heater to last? I've always just assumed you could expect 8-10 years for one.

I don't even know how old my gas heater is. 20+ or so, I forget.

Datsun310Guy wrote:

z31maniac wrote:

92dxman wrote:

ddavidv wrote: I only know electric water heaters, and they are sort of the same as entry level riding mowers = they are all junk. Just plan on replacing every 8-10 years.

+1. The one in my house was starting to crap out and with it being almost 8-9 years old, it made more general and financial sense to just replace it. Brand new heater was installed next day. Parts for the old one would have taken a week or so to arrive due to the age of the heater.

So how long do you guys expect a gas heater to last? I've always just assumed you could expect 8-10 years for one.

we have "hard" water and a softener - usually 5-7 years is it.

+3.

I've got pretty crappy water with high iron content. Plus, I'm a single guy and don't use a lot of water, so any sediment in the water heater has plenty of time to settle out. So far I've replaced my water heater twice since 1992 when I moved in.

When I renovate my house and redo the plumbing, I plan to add at least a sediment filter and provisions for additional treatment.

Btw: technology has made replacing a water heater damn near idiot-proof:

http://www.homedepot.com/p/SharkBite-3-4-in-x-18-in-Flexible-Water-Heater-Connector-3-4-in-with-Ball-Valve-u3088flex18bvlf/202685676?N=bux3Z1z114tc

^You realize twice in 20 years is one every 10 years.......like I mentioned.

z31maniac wrote: ^You realize twice in 20 years is one every 10 years.......like I mentioned.

Not necessarily! Could be the first one was in year 1 and the next one in year 19, indicating an 18-year interval. Just sayin'.

1988RedT2 wrote:

z31maniac wrote: ^You realize twice in 20 years is one every 10 years.......like I mentioned.

Not necessarily! Could be the first one was in year 1 and the next one in year 19, indicating an 18-year interval. Just sayin'.

We are talking about averages here.

Keep up.

z31maniac wrote: ^You realize twice in 20 years is one every 10 years.......like I mentioned.

And did you read my post long enough to notice I was agreeing with you? jezus effing christmas...

Actually... I think I got a bit more than 10 years. First time was around '97 or so and who knows how old it was since it was already in the house. The second time was 3 or 4 years ago.