Plumbing in the Home/hot water
QUESTION: Hi Louie,
The situation is a residential electric water heater, 50-55 gallons. To save money I put it on a countdown timer so we only heat the water when we’re going to use it. The settings on the timer in minutes are 10, 20, 30, 60, and hold.
The shower head is 1.6 gallons per minute.
The water is usually running for about 10 to 15 minutes for one shower and the other usually takes 5 to 10 minutes.
M – F there is no problem, the first shower heats for 30 minutes and the second shower heats for 20 minutes about 2 to 3 hours after the first.
On the weekends we are in habit of taking a shower one right after the other without shutting off the water. Logic states 30m plus 20m equals 50 minutes. So we tried the timer on 60m and the second shower ran out of hot water. Then we tried stopping the shower for 5m between showers and that was worse.
Last weekend we tried 60m, then when the first person started the shower we started the timer at 30m and the second shower ran out of hot water.
So, closer to the point, I would like to understand how water flows in an electric hot water tank. I’m trying to find the solution to save money and not run the electric longer than I need to, but also take a comfortable shower without running out of hot water.
ANSWER: I have to run out the door so can't answer this fully until I get back tonight. But there is no such thing as a 50-55 gallon and it is VERY important I know what size it is? You are probably looking at the energy guide that shows how many gallons per hour it will produce, which is 50-55. It is probably a 40 gallon heater. Please look on an official looking sticker on heater that shows model, serial number and us gallon capacity and let me know the size of it.
---------- FOLLOW-UP ----------
QUESTION: Hi Louie,
The 50-55 gallons was a guess,sorry, it's actually 50 US gallons
General Electric, model number SE50M12AAH
Okie Dokie. Im back!!! Ok, do me a favor would you? Take that timer and TRASH IT!!! Just take the wires and by-pass that stupid, won't save you anything timer and get rid of it!!!!
Next, you are asking WAY too much out of a 50 gallon water heater. It's not that scientific, trust me, about saying your showerhead flow is this and im in there for this amount of minutes... You must be driving yourself CRAZY with stop watches and all while you shower...geez, give it a rest :)
You want more hot water capacity, jack up the 2 thermostats to about 140 degress and that alone will produce about a 20% increase as the hotter the water, the LESS you need to open the hot water valves to get the temp you want. Your water heater is the LEAST of your electric bill concerns. You want to save electricity, hang your clothes out to dry, your dryer burns up a lot of it, not to mention your heater and AC.
Any hoot, 50 gallons will produce about a little under a 30 min shower, about 25 mins, depending on your water pressure and shower head reducer inserts. Thats a MAXIMUM of 25 mins.....BEST CASE with reduced flow and reduced shower head reducers installed. I don't see where you are having an issue? It will also take about 30 mins to get it back up to full temp IF you completely deplete it. So weekends you're just not giving it enough time to completely heat up again. Its that simple. You're asking more out of it than it can give you. Jack up the temp OR put in an 80 gallon if you REALLY dont want to ever run out of hot water.
So the second, weekday shower for 20 mins is not correct. Second shower on week days will run EXACTLY as long as the first shower on weekdays, because it heats up in 30 mins and you're waiting 2-3 hours in between, MORE than enough time for it to heat up again. That is a dumb TIMER issue....