This product is a positive pressure sensing switch that recognizes air pressure and activates the product from an independent electrical circuit. This sequence prevents the need for more connections through the appliance's circuit which may void the manufacturers' warranty as well as manual systems.
| Product Type: | Switch |
|---|---|
| Supply Voltage: | 115v |
| Amperage: | 3.8 |
| Warranty: | 5 Year |

Hi Faith. Within ten seconds of the dryer beginning operation, positive pressure in the duct causes the switch diaphragm to close, activating the electronic timer circuit. The timer directs power to the fan in consecutive five minute cycles, effectively providing continuous boost as long as the dryer is on. When the dryer finishes its operation, the fan will complete the five minute cycle that it had started before the dryer stopped and then it will begin one final clearing cycle of five minutes. This means that the fan will continue to run for between five and ten minutes after the dryer has stopped.
.25 od
It does run on the pressure in the vents. It works with the positive air flow generated by the fan, which should run for about 10 minutes.
This sounds good but at times wind will also enter the vent and create positive pressure that starts the fan. Unfortunately, the fan that my unit is attached to is noisy, so this is a problem.