40gal orphaned tank failing. Tank or tankless?

[B Resch]

I have a 20ish year old 40k 40 gal tank that is starting to leak. It’s currently vented with 3” into an old clay lined chimney. Nothing else is vented in that chimney as the furnace if high efficiency. I’m in northern WI with wife and 3 daughters. Currently we fight about hot water each evening at shower/bath time so my replacement needs to be an upgrade. My understanding is that I can’t do an atmospheric vent anymore in that chimney without a separate smaller flue (true?). I looked into doing a direct vent tank but have nowhere to go with the vent due to windows and the existing furnace vents. The only thing vent wise I can fit is a power direct vent. Next issues is no one in my area seems to have power direct vent tanks in stock…all out to mid march delivery. Am I a going to regret switching to a tankless? HD has rheem 199k tankles models with recirculating pumps built in for less than I can order a power direct vent tank after tax rebates. I’m going to be doing the install. Not a pro myself but familiar enough with gas/water/ and electrical to do it right. Thoughts?

 

[Breplum]

can’t do an atmospheric vent anymore in that chimney without a separate smaller flue (true?) True, it was never actually legal unless the clay was within the charts of the mechanical/plumbing code. reason being that the cold mass of masonry doesn't play well with heat trying to rise. so, diameter and height all come in to reading the chart on masonry chimney.
You will need to increase your gas pipe with tankless. We only use Navien condensing NPE A2 series for tankless because we like the built in buffer tank along with the pump, plus the multi line display really is easy to use, but, I hear what you are saying about cost of a tank WH with only 6 yr. pro rated warranty.

 

[Sponsor]

 

[B Resch]

can’t do an atmospheric vent anymore in that chimney without a separate smaller flue (true?) True, it was never actually legal unless the clay was within the charts of the mechanical/plumbing code. reason being that the cold mass of masonry doesn't play well with heat trying to rise. so, diameter and height all come in to reading the chart on masonry chimney.
You will need to increase your gas pipe with tankless. We only use Navien condensing NPE A2 series for tankless because we like the built in buffer tank along with the pump, plus the multi line display really is easy to use, but, I hear what you are saying about cost of a tank WH with only 6 yr. pro rated warranty.

 

[B Resch]

gas line size should be okay (I’ll verify) the location is about 5’ from the meter, so if I have to up it for a few feet it’s fine. I’ve always used tank water heaters because I had read the payback on tankless didn’t usually work out, but with the current rebates I can do a tankless for essentially the same price as an atmospheric tank. Am I overthinking this or is there some other drawback I’m not seeing going to the tankless vs waiting 3 weeks for a direct power vent tank to come in. My current one works but is leaking due to rust and I fear it could completely fail any day.

 

[Fitter30]

They make a flue liners for condensing and non condensing applications. Chimmy sweep can install one.
Green bay lowes or home depot probably has one ooe a plumbing supply

 

[B Resch]

They make a flue liners for condensing and non condensing applications. Chimmy sweep can install one.
Green bay lowes or home depot probably has one ooe a plumbing supply

If it were summer I’d consider it, but I have a 3 story house with a steep pitched roof that’s currently covered in snow. Only way up would be a big man lift. I imagine that’s not gonna come cheap.

 

[Fitter30]

You can take a powered vent through the side wall.

 

[B Resch]

You can take a powered vent through the side wall.

No. That was my first plan but I can’t find a spot with the proper clearances for just a powered vent. Lots of big openable windows are nice that way.

 

[John Gayewski]

The only reason to get tankless is if you need endless hot water. It sounds like you do need that with a family. So yeah go ahead. I don't think you be sorry, but get a Navien. They are pretty popular and easy to get parts and what not. At least that true in my area.

 

[Taylorjm]

So nobody seems to be commenting about the size unit he’s considering. That’s the biggest factor for tankless. With a family that size you need to make sure the flow rate with the necessary rise will be adequate. Otherwise if you go to small you will end up with a trickle of hot water. Unless you have at least 3/4” gas line without too much distance or 90’s but that depends on the unit size too. Also how do you plan to vent a tankless? It has to go out the side just like a power vent tank style too. I personally went with a hybrid model. It’s a 20gal stainless tank with a high capacity burner up through the middle. It gives you 20gal of hot water right away then when the burner kicks on it operates like a tankless and gives near endless hot water. So if you turn on a faucet to wash your hands you don’t need to wait for hot water. It also heats the water to 140-160 degrees and mixes in cold water out to the faucets, so that 20 gal of hot goes much further. Personally I don’t care for tankless. Too much maintenance and just don’t act like a tank with hot water storage. The hybrid model I have it will heat the 20 gal of water to temperature in under 5 min so nothing like the recovery of a full tank model and uses less gas that way.

 

[B Resch]

I was considering a 200k tankless because it was the largest I was seeing locally. We only have 1 nice shower today so there are never situations with multiple simultaneous showers or baths, there is almost constant laundry or dishes with 4 females in the house. I might redo a bathroom in the future to add a second shower but that’s at least a couple years out.

As for venting, I do have clearances for a powered vent direct vent, just not a power vent. From reading the install guides I’ve gotta stay at least 12” from my openable windows with power direct which is possible, it’s the 4’ from openable windows with the standard power vent I can’t meet.

All the hybrid models I see listed are electric. You have me intrigued by this 20gal gas hybrid? Who makes those?

 

[Taylorjm]

I was considering a 200k tankless because it was the largest I was seeing locally. We only have 1 nice shower today so there are never situations with multiple simultaneous showers or baths, there is almost constant laundry or dishes with 4 females in the house. I might redo a bathroom in the future to add a second shower but that’s at least a couple years out.

As for venting, I do have clearances for a powered vent direct vent, just not a power vent. From reading the install guides I’ve gotta stay at least 12” from my openable windows with power direct which is possible, it’s the 4’ from openable windows with the standard power vent I can’t meet.

All the hybrid models I see listed are electric. You have me intrigued by this 20gal gas hybrid? Who makes those?

Made by htp. I love mine and I don’t remember the model I got but you can usually use the same 1/2” gas line. Mine may have been a 75,000 btu.

Energy Star rated highly efficient residential tank type water heater

Revolutionary, most efficient and affordable residential water heater in the industry made with advanced stainless steel fire tube heat exchanger.

www.htproducts.com

 

[Fitter30]

Had 6 people in my house 3 adults, 18, 16 and 14. Three and three. 50 gallon gas two full baths. Never had a problem with showers unless

I was considering a 200k tankless because it was the largest I was seeing locally. We only have 1 nice shower today so there are never situations with multiple simultaneous showers or baths, there is almost constant laundry or dishes with 4 females in the house. I might redo a bathroom in the future to add a second shower but that’s at least a couple years out.

As for venting, I do have clearances for a powered vent direct vent, just not a power vent. From reading the install guides I’ve gotta stay at least 12” from my openable windows with power direct which is possible, it’s the 4’ from openable windows with the standard power vent I can’t meet.

All the hybrid models I see listed are electric. You have me intrigued by this 20gal gas hybrid? Who makes those?

For tankless need lowest water temp and highest gpm for btu temp rise. Also need to watch a couple of you tube videos yearly maintaining.

 

[Taylorjm]

In my vacation home I have an amtrol boiler mate. Has a coil inside that runs off a zone valve connected to the boiler used for heat so no exhaust for the hot water. This was the first time I ever saw one of those. I don’t know how efficient they are, guess it depends on the boiler they are connected to and not sure the recovery rate but we have had 10 in the house all taking showers and laundry and never had an issue. It’s an advantage in our area because several people with a standard water heater have issues with the anode rod making the water smell and have to replace it with another kind. Don’t have that issue with the amtrol since it’s some kind of plastic lined tank inside. Not sure if that’s an option for you.

 

[Joe Obresely]

I have a 20ish year old 40k 40 gal tank that is starting to leak. It’s currently vented with 3” into an old clay lined chimney. Nothing else is vented in that chimney as the furnace if high efficiency. I’m in northern WI with wife and 3 daughters. Currently we fight about hot water each evening at shower/bath time so my replacement needs to be an upgrade. My understanding is that I can’t do an atmospheric vent anymore in that chimney without a separate smaller flue (true?). I looked into doing a direct vent tank but have nowhere to go with the vent due to windows and the existing furnace vents. The only thing vent wise I can fit is a power direct vent. Next issues is no one in my area seems to have power direct vent tanks in stock…all out to mid march delivery. Am I a going to regret switching to a tankless? HD has rheem 199k tankles models with recirculating pumps built in for less than I can order a power direct vent tank after tax rebates. I’m going to be doing the install. Not a pro myself but familiar enough with gas/water/ and electrical to do it right. Thoughts?

There are pros and cons to both tankless and tanked water heaters. But the next biggest question I get, and you'll run into, is gas vs electric tankless water heaters and choosing which is right for you. I've got this question/dilema from enough people that I wrote a post about this specific plumbing roadblock people come to. You can view it here: https://www.rightnowplumbingmt.com

 

[B Resch]

Made by htp. I love mine and I don’t remember the model I got but you can usually use the same 1/2” gas line. Mine may have been a 75,000 btu.

Energy Star rated highly efficient residential tank type water heater

Revolutionary, most efficient and affordable residential water heater in the industry made with advanced stainless steel fire tube heat exchanger.

www.htproducts.com

Looks interesting but don’t see any dealers online or near me.

 

[Taylorjm]

Looks interesting but don’t see any dealers online or near me.

Mine was actually made by Westinghouse and I got it at Menards. Home Depot also carries a brand and I think they are all made by htp

 

[Master Plumber Mark]

Just throw in a new 50 gallon heater or a 75 and be happy... I have a 75 gallon brad white venting
into a clay tile chimmney and it has been this way for well over 15 years.... You will have to chisel out
some of the brick to get a 4 inch flu pipe up into the chimmney and it will probably draw just fine
and work for 30 years...

their is no such thing as "flu pipe police" out there that are gonna get you in trouble...

or you can throw in a 50 or 75 gallon power vent and vent it out
the side of the house if you so wish.....

 

[Taylorjm]

Just throw in a new 50 gallon heater or a 75 and be happy... I have a 75 gallon brad white venting
into a clay tile chimmney and it has been this way for well over 15 years.... You will have to chisel out
some of the brick to get a 4 inch flu pipe up into the chimmney and it will probably draw just fine
and work for 30 years...

their is no such thing as "flu pipe police" out there that are gonna get you in trouble...

or you can throw in a 50 or 75 gallon power vent and vent it out
the side of the house if you so wish.....

I agree. Too many times people will overthink and overcomplicate something that has worked for years. Tank models today have higher recovery rates than years ago.

 

[B Resch]

I agree. Too many times people will overthink and overcomplicate something that has worked for years. Tank models today have higher recovery rates than years ago.

I’m starting to lean that way…. If my 40k water heater today doesn’t backdraft orphaned, theoretically wouldn’t a higher BTU model draft better? I can get a 75gal, 75k btu at Menards relatively cheap and fast. I’ve got a 3” single wall going to the chimney today but chiseling it out to 4” wouldn’t be anything.

As a side note, I have had all this week to think on it because I’m on vacation. (Tank is drained and shut off? I get home tomorrow night so Thursday it will be go time on making a real decision.