Columbia CT Series, Installation, Operation And Maintenance Manual

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FM-148 COLUMBIA BOILER COMPANY, REV 6-06
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Installation
The Columbia Model CT Direct Vent Series Steam Boiler is furnished completely piped,
wired, and assembled. It has been test fired at the factory and is ready for installation. This
steam boiler is designed to operate with natural gas, and is suitable for standard AC elec-
trical service. The CT Series requires the following minimum clearances to combustible
material: top, sides, and rear - 18", front - 36", flue vent duct - 18".
Location
The CT boiler must be mounted on a level non-combustible floor, or the floor must be pro-
tected in accordance with the requirements of accepted building code practices. In the
absence of local codes, it is suggested that NFPA-31 section 4-4.1.5 be followed.
Flue Vent Duct
For direct venting, galvanized smoke pipe is acceptable, but local codes take precedence.
The maximum length of flue vent duct allowed is 40 feet, and at no time can the diameter
of the flue vent duct be less than the diameter of the smoke outlet of the boiler, see Table
on the previous page for size. The flue pipe should be sloped upward 1/4" per horizon-
tal foot of run. All sections of flue pipe should be joined and fastened securely with sheet
metal screws. The maximum number of 90° elbows in the flue vent duct is four. A baromet-
ric swing type draft regulator may be installed in the flue vent duct if desired, but is not
necessary.
The vent must end with the UL listed vent cap that was shipped with your boiler. the vent
cap can be installed either horizontally (Figure 5-A below) or vertically with a tee (Figure
5-B below). It is suggested that a screen or vent pipe plug be inserted into the bottom of
the tee to prevent animals and other matter from entering.
Figure 5