Specifications

6 720 644 063

Installation instructions

3.3.2 Clearance Requirements from Vent Termi-

nations to Building Openings

All clearance requirements are in accordance with ANSI

Z21.10.3 and the National Fuel Gas Code, ANSI

Z223.1 and in Canada, in accordance with

NSCNGPIC.

Vent Clearances When Heater is Installed

Indoors (For 660 EF appliance)

Maintain the following clearances to any opening in any

building:

• 4' (1.2m) below, 4' (1.2m) horizontally from, or 1'

(0.3m) above any door, operable window, or gravity

air inlet into any building. 3' (0.9m) above any forced

air inlet within 10' (3m).

Fig. 9

For Installations in Canada, clearances are as follows:

To windows, doors, & gravity air inlets: 36" (900mm). To

forced air inlets: 6' (1.8m). These clearance require-

ments hold true for all of the above situations: Indoor.

Outdoor Clearances to Opening into any Building

(For 660 EFO appliance)

Maintain the following clearances to any opening in any

building:

• 1' (0.3m) below, 1' (0.3m) horizontally from, or 1'

(0.3m) above any door, operable window, or gravity

air inlet into any building. 3' (0.9m) above any forced

air inlet within 10' (3m).

Fig. 10

Vent Clearances When Heater is Installed in a

Recess Box (For 660 EFO appliance)

Fig. 11 Recess box installation with cover removed

Maintain the following clearances to any opening in any

building:

• 1' (0.3m) below, 1' (0.3m) horizontally from, or

1' (0.3m) above any door, operable window, or grav-

ity air inlet into any building. 3' (0.9m) above any

forced air inlet within 10' (3m).

Fig. 12

For Installations in Canada, clearances are as follows:

To windows, doors, & gravity air inlets: 36" (900mm).

To forced air inlets: 6' (1.8m).