Installation Manual

H-Series Demand Duo™ 2 Installation and Operation Manual 20

When positioning the tank and connecting water, follow these guidelines:

• Water connections to the Demand Duo™ 2 must follow all state and local plumbing codes.

• When assembling the hot and cold water piping, use a high quality food grade pipe joint compound

and ensure all fittings are tight.

• DO NOT apply an open flame to the inlet and outlet fittings, as heat will damage or destroy the

plastic lined fittings. This will result in premature failure of the fittings, which is not covered by the

warranty.

• For standard installations, refer to the Piping Diagram for Basic Installations in the Appendix.

To position the tank and connect water:

1. Position the tank in the desired location.

2. Connect piping to the cold water inlet connection (1.5 in./38 mm MNPT). See A in image below.

• Keep the pipe as close as possible to one side of the tank; this allows the rack frame to position

closer to the tank and allow for easier flex line connection (see B).

• Maximum pipe length from the cold water inlet connection to the rack frame leg is 17.77 in.

(451 mm) (see C).

3. Connect piping to the hot water outlet connection (1.5 in./38 mm MNPT) (see D).

4. Install a shut-off valve on the cold and hot water lines (see E).

5. Rinnai recommends to install unions on the cold and hot water lines so that the water heater can

easily disconnect if servicing is required (see F).

17.77 in.

(451 mm)

MAXIMUM

Keep pipe close to tank