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6
4.6 High Altitude
These heaters are CSA-approved (without
modifications) for installations up to 2000' (610
m) in US and Canada. CSA approved heaters
installed above 2000' (610 m) must be de-rated.
For installations above 2000' (610 m) in US,
consult factory for information on burner de-
rating. For installations from 2000' (610 m) to
4500' (1370m) in Canada, high altitude
conversion kits are available. Heaters installed
over 4500' (1370 m) in Canada are not CSA-
approved and must be approved by the local or
provincial authority.