I have a cottage with a 120v (1500W 15 gallon) water heater. It's
made by Simpsons-Sears so let's assume it's about 20 years old. It is
located in the bathroom.
I'd like to relocate this heater to the attic and will follow the
usual precautions (drain pain, drain tube to outside, etc.). While
relocating the heater, I'm considering replacing it due to the age of
The only power this unit can have is 120v on a dedicated 15A breaker.
This is a "circuit breaker" type fuse screwed into the original 60A
panel in the cottage.
Can I use a 240V water heater and what will be the difference in
recovery time? There is only one shower in the cottage (no tub,
washing machine, dishwasher etc.) so there is very little hot water
used. Max 2 showers/day plus whatever hot water is used in the sink.
I'd like to replace the 15gal unit with a 30gal 240V unit running at
120V. I understand that the unit will only heat up 1/4 as fast at
120V. So if the unit I'm looking at says "Recovery time to 90 degrees
= 21 Gal/hr" does this mean my unit will recover at about 5 gal per
hour or 6 hours to recover the entire tank? I can live with this
considering we use 15 gals or less a day anyhow (based on the existing
Am I on the right path here thinking that 6 hours to recover the tank
is about right, or will I be waiting longer for hot water? I may also
consider turning the temperature up a bit on the tank (to minimize the
hot/cold ratio of water produced) since there is a scald-proof fixture
in the shower.