Rinnai R-53

I inspected a new home with the above, but can not find on their web site if the above water heater is a single use type or for multiple use.
Anyone know?

Good question… Looks like that model was phased out. Here is one with the same flow rating.

I did some research and found that the model numbers below 75 would not be very good for a whole house, even a 2 bath one even though they may be rated for it.

The R-53 is max 5.3 gpm and uses only a 3/4 in gas line and the 75 is 7.5 gpm

The problem I find the most is where they have a good unit with only a 3/4 inch gas line on a 3 or 4 bath house. For a whole house you need a one inch gas line and even 1.5 inch gas line on some.

I saw a model 85 on an old two bath condo the other day. I couldn’t run it since they forgot to put in a 120V receptacle for it.

I think most people will be very disappointed in these unless you have a recirc loop which also needs at least a 2.5 gallon tank or a small house with no more than 20 foot runs. The flow rates are less and it just takes too long to get that endless hot water to where you want it.

Thanks for the help.
I could not find the R-53 but did find the r-53 e on the web.