Installation & Operation Manual
2
Venting
(continued)
25
Horizontal DirectAire™ venting
(Powered Venting)
- see page 14.
The Horizontal DirectAire™ vent system is the same as the Sidewall Venting system, except it pulls combustion
air from the outdoors through a sidewall air inlet. Follow all requirements in Sidewall Venting section on page 22.
The Horizontal DirectAire™ vent system requires you to install two pipes directly to the unit; one pipe for flue
products and one for combustion air. Install both pipes horizontally with a sidewall termination point. For this
venting option, you must purchase the DV box accessory from the appliance manufacturer. The DV box attaches to
the air inlet of the unit. The pipe for combustion air attaches to the DV box (see FIG. 2-11 on page 28). Reference
page 28 for a list of approved air intake materials.
Make vent connection directly to the top of the unit. No additional draft diverter or barometric damper is required
on single unit installations with a dedicated stack and a negative draft maintained between 0.04 to 0.08 inches w.c.
The Horizontal DirectAire™ combustion air supply system has specific vent material and installation requirements.
The air inlet pipe connects directly to the boiler to supply combustion air. The combustion air inlet pipe is a
dedicated system with one air inlet pipe per boiler. You must connect the air inlet pipe to a combustion air inlet
cap as specified in this section.
Combustion air supplied from outdoors must be free of contaminants (see the Combustion and Ventilation Air
section on page 10).
NOTICE
Before installing a venting system, follow all requirements found in the General Venting section.
You must order the Horizontal DirectAire™ Vent Kit for sidewall installation from the appliance manufacturer. See Table 2D for
kit numbers. Each kit includes a sidewall powered vent cap fan, proving switch, controls, combustion air inlet cap to supply air to
a single unit, the transition adapter to attach the field supplied single wall air inlet pipe to the unit and installation instructions.
Purchase flue pipe and air inlet pipe locally.
The sidewall air inlet cap supplied in the Horizontal DirectAire™ Vent Kit is used to supply combustion air to a single boiler.
Combustion air supply pipes from multiple units can not be combined into a single air inlet pipe and inlet point.
WARNING
Only use the sidewall air inlet cap recommended by the appliance manufacturer. Using another sidewall air
inlet cap may result in operational problems and the spillage of flue products. Spillage of flue products can
cause personal injury or death due to carbon monoxide poisoning.
Venting of flue products
For venting flue products horizontally, follow all requirements in the installation instructions for sidewall venting.
Termination point for the flue products must follow the clearance requirements in the Sidewall Venting Termination section on
page 22.
For proper operation, a barometric damper is provided for Horizontal DirectAire™ installations. The damper will help to ensure
a draft between negative 0.04 to 0.08 inches w.c.
TABLE - 2D
HORIZONTAL DIRECTAIRE™ KITS
MODEL
KIT MODEL
KIT
402
HDK3031
992
HDK3026*
502
HDK3031
1262
HDK3027*
652
HDK3032
1442
HDK3027*
752
HDK3032
1802
HDK3028*
--
--
2072
HDK3028*
*These kits include a barometric damper.
12"
MIN
3'
MIN
D