How much water?

[rama777]

I am buying a tankless water heater for my new airstream but I'm not sure how many gallons per minute I should get. The five I'm looking at are rated at 1.2, 1.6, 3.2, 2.7, or 3.7 gpm. Any suggestions? Thanks!

[TomW]

More like "How much current?"

The short answer is get the biggest one your 30 amp service will handle & still run the air conditioning.

What are the electrical current ratings on your five choices? You will have to add a circuit breaker for the water heater.

Tom

[Druupy]

The water pump in my unit does 2.7 gallons per minute.
I use about half hot and half cold in the shower, that makes 1.35 gallons of hot per minute.
On city water about 1.7 gallons of hot per minute due to higher pressure.

[overlander63]

Based on Druupy's figures, probably the 2.7 would be best for you, if your electrical system is up to the task.