Noritz N-0931M-OD Installation Manual

Installation Instructions for RB-900 Recess Box

(For Models N-0931M-OD, NR111-OD, NRC83-OD, NRC98-OD, and NRC1111-OD )

1) Determine the installation location.

• The recess box should be installed so the discharge vent maintains the minimum

allowable clearances as required by the local authority. Where no local requirement
exists, maintain the following minimum suggested clearances from building openings
as shown in Figure 1:

1’ below, 1’ horizontally from, or
1’ above any door, operable window,
or gravity air inlet into any building.
3’ above any forced ai r inlet within 10’.

• Follow all other installation requirements

as outlined in the Installation Manual.

Note: Top, front, and side clearances noted
on the front cover of the water heater are not
applicable when installed in a recess box.

Figure 1: Discharge Vent Clearances.

1'

1'

1'

3'

This recess box has been designed to be mounted in a wall cavity. Do not attempt to mount the recess box
in another configuration (i.e. outside wall, free standing, etc.). Damages resulting from an improper installation
will not be covered by the Noritz America Limited Warranty.

2) Construct the framing.

• Prepare an opening for the recess box to

the following approximate dimensions:
39-1/2” (height) x 18-5/8” (width) x
10-1/8” (depth)

Note: The recess box is approved for
zero clearance to combustibles.

3) Prepare the recess box.

• Drill 3 holes in the recess box

to accommodate the water and
gas lines. Suggestions for the
holes are shown in Figure 2.
Additional holes for running
the electrical and remote
controller wires will be
needed as well.

Warning

Note: Allow for drainage
from the pressure relief valve.

Figure 2: Piping options.