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We no longer carry TD121B
Unavailable since April 15, 2025
MANUALS (1)
Product Highlights
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120°F to 170°F
Series 21
Description
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Selectra Series 21 systems are designed primarily for make-up air heating, as components of indirect fired units with atmospheric burners.The Series 21 is designed for single furnace operation.
Remote Selector and Discharge Temperature Sensors must have the same temperature ranges to be compatible.
Remote Selector and Discharge Temperature Sensors must have the same temperature ranges to be compatible.
Specs
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| Temperature Range (F): | 120°F to 170°F |
|---|---|
| Used With: | Series 21 |
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