40gal orphaned tank failing. Tank or tankless?

[Master Plumber Mark]

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.

The hardest thing about upgrading to a 75 is getting the dam thing down into the basement without banging it up
You should certainly upgrade the flu pipe going into the chimmney to at least 4 inch---- or chisel it out to 5 inch
and throw a 5x4 reducer into the chimmney and then drop down to 4 inch to the heater
and really give it some draft

either way will work

 

[B Resch]

Ugh. Well I just did a draft test on my current setup and it backdrafts. I opened the cleanout in my flue to poke around and its actually an 8" x 13" flue, so way oversized. I don't even have my dryer, bathroom fan, or range hood running.

I did some more measuring and poking around the house and I think I have an option to do a do a regular power vent, not the power direct. There is an existing capped at the bottom 2" PVC pipe running up one of my chimney's unused flues that stick up through the top of the chimney. I measured it up and in total with the elbows I would need, I am right at the 55' total length limit I am seeing on various 50gal power vent water heaters.

Now getting into picking a power vent water heater.... the big box stores seem to only carry 40k BTU ones (Rheem/Richmond around me), but AO Smith makes a 50k BTU power vent. Would that extra 10k make a real world difference for back to back showers?

 

[Sponsor]

 

[Taylorjm]

Ugh. Well I just did a draft test on my current setup and it backdrafts. I opened the cleanout in my flue to poke around and its actually an 8" x 13" flue, so way oversized. I don't even have my dryer, bathroom fan, or range hood running.

I did some more measuring and poking around the house and I think I have an option to do a do a regular power vent, not the power direct. There is an existing capped at the bottom 2" PVC pipe running up one of my chimney's unused flues that stick up through the top of the chimney. I measured it up and in total with the elbows I would need, I am right at the 55' total length limit I am seeing on various 50gal power vent water heaters.

Now getting into picking a power vent water heater.... the big box stores seem to only carry 40k BTU ones (Rheem/Richmond around me), but AO Smith makes a 50k BTU power vent. Would that extra 10k make a real world difference for back to back showers?

So there's a pvc pipe running up one of the flues already? What was there? So there isn't anywhere else you can run a power vent in the basement out another wall or anything that would be shorter run than up the chimney pvc? We ran a 50gal power vent for years. It was a richmond but did end up replacing the power vent unit a couple times.

 

[Master Plumber Mark]

Ugh. Well I just did a draft test on my current setup and it backdrafts. I opened the cleanout in my flue to poke around and its actually an 8" x 13" flue, so way oversized. I don't even have my dryer, bathroom fan, or range hood running.

I did some more measuring and poking around the house and I think I have an option to do a do a regular power vent, not the power direct. There is an existing capped at the bottom 2" PVC pipe running up one of my chimney's unused flues that stick up through the top of the chimney. I measured it up and in total with the elbows I would need, I am right at the 55' total length limit I am seeing on various 50gal power vent water heaters.

Now getting into picking a power vent water heater.... the big box stores seem to only carry 40k BTU ones (Rheem/Richmond around me), but AO Smith makes a 50k BTU power vent. Would that extra 10k make a real world difference for back to back showers?

You should get the Rheem power vent.... perhaps you can tie into the pvc line going up the chimmney...

good luck

 

[John Gayewski]

I'm about sick if this thread but a tankless is about the only thing that will give you enough hot water and should be readily available.

If you get a tank you could crank it up and mix down to try to extend the amount of shower time you need. But your talking about 5 showers in a row. Have a pro come install a Navien and you'll likley only be happy. Any tank most likey won't satisfy your demand.

 

[B Resch]

I ended up getting the 50gal Rheem power vent. I got scared off of the tankless.

Install went well. The only hiccup I had was I tried venting up the chimney first but back pressure was too high and it kept faulting out. I didn’t have an accurate height measurement on the chimney but knew it was going to be close to borderline for 2”. It turns out when they say 55 equivalent feet they mean it. In the end I vented out the wall, I’m 36” from the openable window when code says 4’ but no code police here so I went with it.