Water heater question - advice needed

[Caleb]

Ok guys, we're needing to replace our 40 gallon(40k btu gas) water heater. Looking at the AO Smith 50 gal(50k btu gas; see link 1) tank with a power vent or possibly a quality tankless(maybe link 2?)...

We have a lesser efficient unit that requires a B pipe, but we're taking the chimney out and needed to vent via PVC. Another reason we are changing is the 40gal only provides maybe 22 mins of reasonably hot water. How hard is it to install a tankless myself vs a standard tank water heater?

http://www.supplyhouse.com/AO-Smith...ne-Power-Vent-Residential-Gas-Water-Heater-NG

https://www.supplyhouse.com/Rinnai-...i-dQW-nMOIB0vxKElJ7whd6sd01pVVWMaApxREALw_wcB

 

[Ericpwp]

I did it because I was taking out the chimney too. Needed to rerun the gas and the water lines. It was the first water heater I replaced. It's doable, I just took it slow and did my research.

I don't get the feeling that it will last as long as a tank, too many parts to wear out/break, time will tell.

 

[Caleb]

I did it because I was taking out the chimney too. Needed to rerun the gas and the water lines. It was the first water heater I replaced. It's doable, I just took it slow and did my research.

I don't get the feeling that it will last as long as a tank, too many parts to wear out/break, time will tell.

Which unit did you get?

 

[Ericpwp]

I got a steal on the Menards brand (Richmond) 199,900 btu version. It seems like a rheam that didn't make the cut. It only goes to 120°, which is fine. I keep it set at 100° and only turn on the hot to shower. I could stay in there all day. It vents with PVC, which is more cost-effective then the ones that need the proprietary vent.


I don't miss the chimney one bit. It's a brick path in the backyard now.

 

[patience0830]

We just replaced the 40 gal unit in the south house with a 50 gal short Rheem Marathon. Considered the tankless variety but the water furnace needed a place to loop the de-superheater so that heat wasn't wasted. Got to practice my copper sweating technique. Liked the idea of the lifetime warrantee on the Marathon too.

 

[wcd]

YouTube is your friend.

 

[dugsagun]

My dad and i replaced our 40 gal heaters with 50s about 5 years ago. Mine was just 3 flexible hoses and was easy peasy, my dads was half a dozen adapters later and finally done. I think his took like half a day while mine took an hour. And yep look for some videos on the subject if u can.

 

[jkaetz]

I debated this years ago when replacing a our water heater. My biggest concern about the tankless systems is our water. Even with a water softener we have crazy mineral deposits. If you have good water quality I think it would be less concerning. If you can do it, I always thought the better idea was to put several smaller tankless units in the locations that needed hot water. No more waiting for the line to clear before getting hot water.

 

[Ericpwp]

^ Right, people think tankless and they think instant hot water. It still takes the same amount of time to traverse the pipes. I was thinking of maybe small electric point of use systems to heat the water in the pipes until the gas heated water gets there, but that's far down the road.

They sell an adapter that you install with the heater to flush the system. They said once a year even with clean water.

 

[DocIndy]

I replaced the 40 gallon Bradford white that came in the house when we built it 6 years ago. Went with a tankless AO Smith. I got the heater, vent kit and valve kit at wholesale since I work for a full service mechanical contractor. I installed it myself in a day. Worth every penny. Set it for 130 degree discharge and never run out of hot water. It uses standard PVC for the flue. I also bought a descale kit that has a chemical concentrate, pump and hoses since I don't have a water softener. Run the chemical through it once a year. Best part... Not heating 40 gallons all day year round.

as far as the Insta-Hot point of use units.... We install them for remote restrooms in warehouses where hot water is only needed for washing hands. Typically you have to have a 220/240 volt circuit for them. Unless you can pull a new electrical circuit for them, they aren't practical.

 

[blacknwhite]

If you are really concerned with instant hot water, you can have that with either tankless or a conventional tanked water heater. Just jave yo set up a smaller return line and a small circulation pump. They make some water heaters that have this option or you can diy.

 

[Ericpwp]

I looked at that, but doesn't that run the tankless nonstop? From what I saw, the warranty is decreased dramatically when it is setup in that config.

 

[Caleb]

I'm looking at the rinnai ruc80in...a few people say I should have a pro do it, that takes cost of water heater from $1300 to about $3000, way over budget. If I can install the rinnai myself, I'll do that....otherwise I'll have to find a tanker instead.

 

[ghitch75]

i do work in Nashville and i sell and install tankless heaters if you decide to go that way....

 

[Caleb]

i do work in Nashville and i sell and install tankless heaters if you decide to go that way....

What brand? What your usual cost to have one installed?

 

[ghitch75]

i sell Takagi...price depends on size and efficiency.....you say you have gas already and a 80% would be around 1k and 90% + would be around $1800....15 year heat exchanger and 5 years on all other parts....

 

[Caleb]

Higher efficient is preferred and must be vented via PVC (whole purpose of a new water heater is because we are getting rid of a chimney)

 

[ghitch75]

90+ will be pvc vent.....how many baths you have?

 

[Caleb]

90+ will be pvc vent.....how many baths you have?

Currently 1 bath, may add a half bath(toilet and sink) later

 

[rosejm]

^ Right, people think tankless and they think instant hot water. It still takes the same amount of time to traverse the pipes.

In my experience, it's actually longer than normal all things being equal. The tankless heater will start to heat up when it senses the flow. Still takes a measurable amount of time to reach operating temp so it becomes Heat-up + Circulation, instead of just Circulation...