Aiko CTH3-200 Manuale Utente

31 of 71

This heater must be vented in accordance with the 
rules contained in this manual and with the following 
national codes and any state, provincial or local 
codes which may apply: 

United States: Refer to National Fuel Gas Code 
NFPA 54/ANSI Z223.1 - latest revision. 

Canada: Refer to Natural Gas and Propane 
Installation Code CSA B149.1 - latest revision.

Exhaust end of heater will accept a 4

"

 (10 cm) vent 

pipe using the vent adapter (P/N 90502700). To 
prevent leakage of condensation, install the vent 
adapter with the seam on top and seal the joint using 
a high temperature silicone sealant. 

Any portion of vent pipe passing through a 
combustible wall must have an approved thimble
to conform with the above listed codes.

Vent pipe must be sloped downward away from the 
burner 1/2''   (1 cm) for every 20' (6 m).

The heater may be individually vented or common 
vented. When venting horizontally, a maximum of two 
heaters can be commonly vented. 

Section 8.9. When venting vertically, a maximum of 
four heaters can be commonly vented. 

The heater may also be installed unvented in certain 
circumstances according to building ventilation codes. 
Refer to the above codes 

and Page 31, Section 8.2 for 

further information. Unvented operation also requires 
compliance with the clearances to combustibles given 
on Page 8, Figure 12.

The bottom of the vent or air intake terminal shall not 
be located less than 1' (.3 m) above grade level.

The vent shall not terminate less than 7' (2.1 m) above 
grade where located adjacent to public walkways.

Vent terminal must be installed at a height sufficient to 
prevent blockage by snow and building materials 
protected from degradation by flue gasses.

Secure all joints with #8 x 3/8 sheet metal screws. 
Seal all joints with high temperature silicone sealant.

Vent terminal must be beyond any combustible 
overhang.

Vent must terminate at least 3' (.9 m) above any forced 
air inlet located within 10' (3.1 m).

Vent must terminate at least 4' (1.2 m) below, 
4' (1.2 m) horizontally from, or 1' (.3 m) above any 
door, operable window, or gravity air inlet into any 
building.

The vent shall not terminate within 6' (1.8 m) of a 
mechanical air supply inlet to any building.

The vent shall not terminate within 3' (.9 m) of a 
window or door that can be opened in any building, 
any non-mechanical air supply inlet to any building, or 
of the combustion air inlet of any other appliance. 

Sufficient ventilation must be provided in the amount 
of 4 cfm per 1000 Btu/h firing rate (United States); 3 
cfm per 1000 Btu/h firing rate (Canada).

Use of optional outside combustion air is not 
recommended with unvented heaters.

If exhaust fans are used to supply ventilation air, an 
interlock switch must be used to prevent the heater 
from coming on when the fans are off. This may be 
done using a pressure switch.