Tankless gas water heater...Rinnai in closet

Just did a large house today. Besides the other gas water heater in the garage the house had this Rinnai R53 tankless gas water heater in one of the closets off the master bathroom. Solid door leading into this 5x6 closet…I am assuming that this unit is the same as any gas water heater in that they need to put a louvered door on the closet and install a drain pan under the unit?


It can be in a closet as long as it has all the requirements of any other water heater, tankless or not.

the installer & others might want to read the manuals

**The vent system must **vent directly to the outside of the building and use outside air for combustion.


This looks like a power vent unit that draws combustion air from the interior but Rinnai also has a concentric venting system that uses one vent for both intake and exhaust…

Here is a link…


Did the vent on the exterior look like this? This is from a home last summer and the vent was the concentric type…model number was RL75i…

Looks like a concentric vent to me. It is drawing combustion air from the exterior. It is a pipe within a pipe type vent