In our new home we have a whirlpool tub. We have a 50 gallon water
heater but it doesn't seem to be enough to fill the tub. I'd like to
put in an in line instant water heater for the tub. We have good
access to the mechanics and plenty of room for the heater. Since there
are plug ins by the workings I'd like to use 110 instead of 220. Will
that give me enough power to run the heater?

gilmoreguy wrote:
In our new home we have a whirlpool tub. We have a 50 gallon water
heater but it doesn't seem to be enough to fill the tub. I'd like to
put in an in line instant water heater for the tub. We have good
access to the mechanics and plenty of room for the heater. Since there
are plug ins by the workings I'd like to use 110 instead of 220. Will
that give me enough power to run the heater?


No, say it is a 20A outlet. It can supply 16A max which is only 6,500
BTU/hr.

At half the voltage, an appliance of the same wattage would require twice
the current.

Try this. Run the hot water just long enough to get some in the tub, maybe
5-10 gal at the most. Now shut it off and wait for the water heater to
finish reheating the water in the tank (this takes a fraction of the time it
takes to heat the whole tank after filling the tub). Now you can finish
filling the tub and have a little hot to spare.

Often when you decide to take a bath, the water in the tank is not really at
its max temp (requireing you to use that much more). This procedure ensures
the WH is completely full with max temp water and provides some in the pipes
(if they are insulated) and the initial draw.


"gilmoreguy" wrote in message
oups.com...
In our new home we have a whirlpool tub. We have a 50 gallon water
heater but it doesn't seem to be enough to fill the tub. I'd like to
put in an in line instant water heater for the tub. We have good
access to the mechanics and plenty of room for the heater. Since there
are plug ins by the workings I'd like to use 110 instead of 220. Will
that give me enough power to run the heater?

"gilmoreguy" wrote in message
oups.com...
In our new home we have a whirlpool tub. We have a 50 gallon water
heater but it doesn't seem to be enough to fill the tub. I'd like to
put in an in line instant water heater for the tub. We have good
access to the mechanics and plenty of room for the heater. Since there
are plug ins by the workings I'd like to use 110 instead of 220. Will
that give me enough power to run the heater?

You want to run a 240v heater on 120v? It will produce one quarter the
heat. If you are just trying to increase the temperature of the water that
comes from your existing water heater, that might be enough. But you will
have to run a circuit for it anyhow; why not just run a 240v circuit?

"gilmoreguy" wrote in message
oups.com...
In our new home we have a whirlpool tub. We have a 50 gallon water
heater but it doesn't seem to be enough to fill the tub. I'd like to
put in an in line instant water heater for the tub. We have good
access to the mechanics and plenty of room for the heater. Since there
are plug ins by the workings I'd like to use 110 instead of 220. Will
that give me enough power to run the heater?


Fixed appliances require separate circuits. Anything attached to a tub in a
bathroom should be on a gfci. Using a existing circuit is not the way to do
it.

Raise the temp of the water heater.