The Castair RDDT115 is a 115-volt timer accessory for Castair RDD series refrigerated compressed air dryers. The T115 designation indicates this is a timer component operating on 115V power — the same voltage as the RDD series dryers themselves. Timer controls for refrigerated dryers manage automatic drain timing: they open the drain valve at set intervals to eject condensate from the dryer sump, providing a reliable timed drain function as an alternative or supplement to demand-based drain sensors.
Castair refrigerated dryers come standard with an automatic demand drain that only cycles when condensate is detected. The RDDT115 timer provides a fixed-interval drain option — useful when the demand drain sensor is being bypassed for testing, when the shop environment produces consistent high condensate volumes that benefit from predictable drain intervals, or as a backup drain control when the primary demand sensor is being serviced.
How Timer-Controlled Drains Work
- Fixed interval operation: The timer opens the drain valve on a set schedule — typically every few minutes for a brief period — regardless of whether condensate is present
- Adjustable timing: Most dryer timers allow adjustment of both the interval between drain cycles and the duration each drain opening
- Compressed air cost: Unlike demand drains, timer drains bleed a small amount of compressed air with each drain cycle — the interval setting should be optimized for your actual condensate rate to minimize waste
- 115V operation: Wires directly into the dryer's electrical system
Compatible Equipment
- Castair RDD series refrigerated compressed air dryers (115V models)
- Confirm exact compatibility with your RDD dryer model before ordering — call 866-217-0063
What's in the Box
- Castair RDDT115 115V timer accessory for RDD series dryers
Wiring diagram and installation instructions available by contacting us. This is a field-installed accessory. Confirm voltage requirements match your dryer before installation.
Technical Specifications
- Part Number: RDDT115
- Manufacturer: Castair (Cast Air, Inc.)
- Operating voltage: 115V
- Application: Castair RDD series refrigerated compressed air dryers
- Function: Drain timer control
- Timing range and cycle duration: Contact us for specifications — 866-217-0063
Why Buy From Air Compressor Factory Direct?
We carry Castair dryer accessories and can confirm whether the RDDT115 is compatible with your specific RDD model and drain circuit. If you are troubleshooting drain performance or upgrading your dryer's drain control, we can walk through the options with you before you order. Free shipping on qualifying orders, free pre-sale technical support, genuine Castair parts.
Call 866-217-0063 for quick answers and help!
