HMI BDD Series – Back Draft Damper
The Hoyme Back Draft Damper comes in two styles. Both are spring return and as a result can be mounted in any position.
| Inset Butterfly Style They typically range from 4″ – 6″ in diameter. Contact Factory if other sizing is required. |  | ||
| Regular Inline Style They typically range from 4 – 24″ in diameter. Contact Factory if other sizing is required. |   |  |  |
Model Number Identification:
BDD – **00 – 000 (-B)
Where ** is the size of the Damper, and for inset Butterfly style add the “-B” to the part number.
For example:
| 12″ Back Draft Damper | 6″ Back Draft Damper in Inset Butterfly Style |
| BDD – 1200 – 000 | BDD – 0600 – 000 – B |
Additionally, another option is the BDH – Back Draft Hood Damper, which comes in two models and choice of two colors:
| Spring Closed – Regular Metal | Gravity Closed – Painted White |
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Features Include:
- An End Switch may also be added to the spring closed model
- Both types are available in either regular or white painted metal
- BDH – Back Draft Hood commonly comes in sizes of 4″ – 12″ in diameter
- Contact the factory if other sizing is required
Model Number Identification:
BDH – **00-x00 (-G)
Where ** is the size of the Damper and x indicates an end switch (with an S or a 0).
For Example:
| 8″ Back Draft Hood – Spring Closed | 8″ Back Draft Hood – Spring Closed – with an End switch | 8″ Back Draft Hood – Gravity Closed | 8″ Back Draft Hood – Gravity Closed – with an End switch |
| BDH – 0800 – 000 | BDH – 0800 – S00 | BDH – 0800 – 000 – G | BDH – 0800 – S00 – G |