Tankless Water Heater guys

[jkaetz]

It looks like our tank WH is going to need replaced soon. 10years old. It is a powered vent unit so cost is going to be comparable to tankless units. Anyone knowledgeable on the current state of tankless vs tank? We do have hard water and a water softener already. It looks like the existing gas line is 1” and feeds the furnace as well ~70k btu I believe.

Will they really last the 20 years they claim with proper maintenance?

 

[indyblue]

WOW, I didn't know tankless heaters have gotten this inexpensive these days. They used to all be in excess of $1.5K but I see Lowes has several good options now from $600-1200 depending on gpm needed.

I'll leave the answer to the longevity to any of our plumbing pro members or those who have had one for extended periods.

My $500 15 year old el-cheapo Bradford White is still going strong. I Just replaced the anode rod after 5-6 years to prevent what you see there.

 

[CTC B4Z]

Have had mine 7 years with hard water. I've done zero maintenance and it's great.

It takes about 10-15 seconds longer to get warmer water. If you have a super long plumbing run you might want to look into a under sink heater on that faucet.

You'll drain your well before you run out of hot water. Lol. We use it to fill our hot tub as well.

 

[rkwhyte2]

Had a tankless heater in the old house and it was the bomb. Mine was electric and came with the house. Lasted about 18 years. I bought the replacement from the manufacturer and because I was an existing customer they cut me a deal. Think I paid right at $900 for the new one and installed it myself. 28,000 Kw(pretty sure I could hear the meter spinning.).

 

[xwing]

I love tankless. We have one main natural gas-powered (actually we use propane, but same heater, just one part different) tankless for most of the house, and 2 smaller electrical ones closer to the destination for 2 bathrooms. The best part is that you cannot ever run out of hot water. It's also nice to not pay to heat water that sits there when you're away. Yes, it does take several more sec to get hot water (at least for the ones that aren't close to their destination.) I like the gas powered one much more than the two electric ones. One thing to note though is that natural gas tankless heaters have different venting requirements than normal tank heaters, so you may have to modify your vent run.

 

[Mr. Habib]

We replaced a 50 gal high efficiency Bradford White with a tankless Rinnai about 10 years age. It's been flawless. Very low maintenance, flush the heat exchanger about once a year, that's it. We can, and do, run 2 showers, the washing machine and dish washer at the same time and never lack hot water. 199000 BTU, 3/4 inch gas line to the the WH off a 1 inch line. I'll never go back. If you're concerned about waiting for hot water at the other end of the house, you can add a recirculating pump.

 

[Mr. Habib]

I love tankless. We have one main natural gas-powered (actually we use propane, but same heater, just one part different) tankless for most of the house, and 2 smaller electrical ones closer to the destination for 2 bathrooms. The best part is that you cannot ever run out of hot water. It's also nice to not pay to heat water that sits there when you're away. Yes, it does take several more sec to get hot water (at least for the ones that aren't close to their destination.) I like the gas powered one much more than the two electric ones. One thing to note though is that natural gas tankless heaters have different venting requirements than normal tank heaters, so you may have to modify your vent run.

Yeah, we went from a 2 1/2 or 3 inch pvc vent through the wall to a 5 inch double wall vent, pvc outside, metal inside.

 

[xwing]

Yeah, we went from a 2 1/2 or 3 inch pvc vent through the wall to a 5 inch double wall vent, pvc outside, metal inside.

Yes, that is common. Although now they do make tankless heaters which can accept pvc venting. Look for "High Efficiency"; they have less cumbersome venting requirements. And prices are way down. You can right now get a good quality whole-house natural-gas tankless at Menards for between $1000-1400 (depending on your BTU requirements).

 

[indyjohn]

If you can go tankless, I would go. Lots of good reasons to, especially if you are already plumbed for gas. One problem I've heard from only 1 person that I know converted to tankless was that he spent more on reconfiguring the exhaust than he did on the heater itself. But if you have a forced air exhaust now, you may avoid the possibility of the problem my friend faced.

 

[WebSnyper]

It looks like our tank WH is going to need replaced soon. 10years old. It is a powered vent unit so cost is going to be comparable to tankless units. Anyone knowledgeable on the current state of tankless vs tank? We do have hard water and a water softener already. It looks like the existing gas line is 1” and feeds the furnace as well ~70k btu I believe.

Will they really last the 20 years they claim with proper maintenance?

The house we moved into 3 years ago had a Rinnai tankless in it from 2008, and it was still going strong. I just replaced it a couple weeks ago, as there was some other plumbing work to be done, and I just decided that at about 15 years old, it had about hit its lifetime, and I'd head it off and get it replaced with a new Navien unit.

We have a softener and we had the Rinnai flushed/serviced each year, and I'm confident the previous owners kept it serviced as well. Will do the same with the new water heater.

Ours is gas.

Even going from the old Rinnai tankless the venting changed to different size and material of vent and intake pipe.

The new one actually has a very small internal recirc tank and it can be sent to intelligent recirc so it learns your usage habits. So some tankless apparently are not completely tankless though it's a very small buffer tank internal to the unit.

If you have a particularly long run that takes a bit to get hot water to, they now have recirc valves that you can just put under a sink, etc as well https://www.navieninc.com/accessories/navicirc

 

[Creedmoor]

We replaced a 50 gal high efficiency Bradford White with a tankless Rinnai about 10 years age. It's been flawless. Very low maintenance, flush the heat exchanger about once a year, that's it. We can, and do, run 2 showers, the washing machine and dish washer at the same time and never lack hot water. 199000 BTU, 3/4 inch gas line to the the WH off a 1 inch line. I'll never go back. If you're concerned about waiting for hot water at the other end of the house, you can add a recirculating pump.

This!
I have the big Rinnai in the house and propane Rinnai at the farm. Money well spent.
If you do go tankless buy the extra valve kit to mount under it to ease yearly heat exchanger clean and flush.

 

[Mr. Habib]

This!
I have the big Rinnai in the house and propane Rinnai at the farm. Money well spent.
If you do go tankless buy the extra valve kit to mount under it to ease yearly heat exchanger clean and flush.
View attachment 240199

Ours came with those. Flushing one is a breeze. Connect 2 short garden hoses,a bucket and a small transfer pump. Fill bucket with vinegar,turn off power, open/closed valves. Start pump sit on couch drink beer for an hour. Put everything back the way you found it. Repeat next year.

 

[Creedmoor]

Ours came with those. Flushing one is a breeze. Connect 2 short garden hoses,a bucket and a small transfer pump. Fill bucket with vinegar,turn off power, open/closed valves. Start pump sit on couch drink beer for an hour. Put everything back the way you found it. Repeat next year.

They were like 80 bucks when I installed mine, I balked but I bought them. The waters crusty in Alex, if I hear constant pops and cracks from the exchanger.... Its time.

 

[04FXSTS]

I know this is the "Back Room" and not to be political but this just fits too good not to put it here. Jim.

 

[jkaetz]

Thanks for the input everyone, given the power vent tanks seem to be around $1500 I'm certainly leaning toward tankless. Was looking at the big Rinnai (160k - 200k) units but will look into the Navian units too. The existing WH exhaust is 3" PVC I'm hoping it would be enough to support a tankless system as well.

Does everyone keep the water temp around 120 or do you drop it and just go full hot at the endpoints?

 

[Mgderf]

If you have a 2" line coming into the meter, you should be fine.
You may need to have the meter changed to accommodate the new load.

 

[Brandon]

Our company uses navian. I know the one thing with them is if you have to call customer service, they ask if the intake is ran outside. Guess they want it out otherwise they aren't happy.

Most every tankless I have seen is set at 120⁰

 

[Dean C.]

Not 100% but I rember reading something recently that tankless water heaters qualify for a tax credit currently too!

Tankless Water Heaters: Tax Credits and Rebates You Can Get

You can get a residential energy property credit of $300 if your tankless water heater uses a renewable energy source. Residential energy efficiency credits are no longer in effect as of December 31, 2021, but residential renewable energy products still qualify for tax credits until December 31...

www.attainablehome.com

 

[WebSnyper]

Not 100% but I rember reading something recently that tankless water heaters qualify for a tax credit currently too!

Tankless Water Heaters: Tax Credits and Rebates You Can Get

You can get a residential energy property credit of $300 if your tankless water heater uses a renewable energy source. Residential energy efficiency credits are no longer in effect as of December 31, 2021, but residential renewable energy products still qualify for tax credits until December 31...

www.attainablehome.com

There may be a rebate with your gas company as well. I filed for one with mine last week on the new water heater. Will see if I get it, plus hopefully the tax credit as well.

 

[WebSnyper]

Thanks for the input everyone, given the power vent tanks seem to be around $1500 I'm certainly leaning toward tankless. Was looking at the big Rinnai (160k - 200k) units but will look into the Navian units too. The existing WH exhaust is 3" PVC I'm hoping it would be enough to support a tankless system as well.

Does everyone keep the water temp around 120 or do you drop it and just go full hot at the endpoints?

I had the Rinnai set to 125. I've left the new Navien at 120 and seems fine.