Water heaters in series water is not equally hot thruout the house

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The recovery is not keeping up with the demand. Not by far.

I have two showers running simultaneously at 3.0 gpm with 1.68 gpm being 140 degree water. 1.68 x 2 showers = 3.36 gpm. 3.36gpm x 15 minute shower = 50.4 gallons of hot water in 15 minutes.

The water heater you posted can’t deliver 50.4 gallons of thermostat setting water in 15 minutes. And if it could I would only get two showers........

A 50 gal. 40k btu water heater can’t deliver 50.4 gallons of thermostat setting hot water in 15 minutes with typical cold water temps.

It’s 2.5gpm per showerhead, not per shower. Correct ? Showers are not limited to one head.
Well.,
Now I have to make a video demonstration.,
I'll use 2 different style temperature readings.
And using 2 showers at the same time, yes you can get 50 gallons of hot water.

Stay tuned.

P.s.
you're one of the guys Opinion I respect around here.
 
Well.,
Now I have to make a video demonstration.,
I'll use 2 different style temperature readings.
And using 2 showers at the same time, yes you can get 50 gallons of hot water.

Stay tuned.

P.s.
you're one of the guys Opinion I respect around here.

Have you ever done a draw test on a water heater to check it’s performance ?

If you have then you understand that you will not get 100% of the tank at the thermostat setting. So if you set the tank temp at 140, you will not get 50 gallons of 140 degree water.

If I get a chance I’ll email AO smith and get their official answer. It’s a simple question. Will the water heater deliver 100% of its tank capacity at thermostat setting temp ?

I say no it will not.
 
Most of my customers have showerheads that run between 3-3.5gpm.

Don’t tell anyone.

There’s nothing wrong with a debate. Carry on and make your best case.
 
You miscalculated. 56% of 2.5gpm is 1.4gpm. Not .35gpm.
Correct 1.4gpm
You miscalculated. 56% of 2.5gpm is 1.4gpm. Not .35gpm.
yup., my bed time...
I falsely looked at the 21gallons total used per person and moved that to GPH. Which means it should've been based on 84 GPH., or yes., 1.4 GPM... LOL

so @ 1.4GPM of hot water., per person., at same time that is a lot of use. The hot water tank recovering at a rate of 0.70 GPM What we have is in 15 minutes 10.5 new gallons
2 people shower same time 15 minutes., 42 Gallons of hot water is used. from a 50 Gallon tank you have a net amount of (50-42)+(the Recovery)10.5= 18.5 gallons left 13 minutes. Thats if you take a shower Directly after.
Waiting 5 minutes and you have 15 minute shower time.
45 minutes and you have a Full Tank.

Real world the small delay of someone getting out the bathroom., and then you taking a shower., you tank would've recovered in the real world., At least in my house.
 
Most of my customers have showerheads that run between 3-3.5gpm.

Don’t tell anyone.

There’s nothing wrong with a debate. Carry on and make your best case.
Exclusive 3-3.5 gpm LOL
My thermostat is set around 150 degrees so., I have even less of a problem with running out of hot water., but yeah., 3-3.5 gpm drastically changes the situation LOL.
But real world use is like you stated., different when different variables are tossed in the mix., But looking at the Tankless stat Rise in temp and duty-cycle., This lil Debate changed my mind
:eek::eek::eek:
I see the tankless that has a recirculating function that delivers 4.7 gpm @ 70F rise. Thats amazing., hell., you couple that with a 40-50 gallon hot water heater., you darn near have an endless supply.
 
Have you ever done a draw test on a water heater to check it’s performance ?

If you have then you understand that you will not get 100% of the tank at the thermostat setting. So if you set the tank temp at 140, you will not get 50 gallons of 140 degree water.

If I get a chance I’ll email AO smith and get their official answer. It’s a simple question. Will the water heater deliver 100% of its tank capacity at thermostat setting temp ?

I say no it will not.
Still want to see their response...
 
I appreciate learning from this question. I am also eager to learn from the replies here. The circulating system principle you mentioned is also useful for conserving lots of water.


thanks, I am learning now.

There is a circulating system. I followed the wrong pipe going to the base of the water heater. I kept wondering why the water was warm out of the faucet in the master bath so quickly - just assumed wife had been running hot water in the bathroom. I know even less about circulating systems other than they circulate warm water so you get warm water to further away parts of the system quickly. I like that.

So, the question then is why do the heaters have to be turned up so high to get reasonably warm water? Would the check valve being on its side cause that? or what would be results of that? And why am I not getting hot water equally to all parts of the house, even after running water for like 10 minutes on some faucets?

Hopefully will hear back from the plumber today.

Thanks again for advice, I just like to confirm what is wrong and needs to be done.
 
Still want to see their response...
Straight from AO Smith below.
————————————————-
Good afternoon,

The 50 gallon tank will give 30 gallons of usable hot water so it would depend on the flow rate of the faucet, but the water will decrease in temperate.

Thank you,

LeeAnn
Technical Support
 
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