The Irritrol RD900-EXT-COMPACT 9-Station 24V AC Controller is a true industry classic. Belonging to the legendary Rain Dial-R series, this controller has been trusted by professionals for generations to perform day-to-day, season after season. Designed to effortlessly manage up to 9 distinct watering zones, it utilizes a built-in 120V transformer to reliably power standard 24V AC irrigation valves across extensive residential or commercial landscapes.
While the Rain Dial-R features a familiar, easy-to-use dial interface that makes programming incredibly straightforward, it is also built for the future. It is fully compatible with Irritrol's advanced upgrades, including SMRT Logic for mobile device programmability and CLIMATE LOGIC wireless weather sensing for worry-free, automatic schedule adjustments. With robust features like water budgeting, program stacking, and a master valve/pump start circuit, this controller marries time-tested durability with modern convenience.
Detailed specifications for system planning.
| Specification | Details |
|---|---|
| Controller Type | AC Powered, Multi-Station |
| Stations | 9 Stations |
| Power Input | 120V AC (Internal Transformer) |
| Power Output | 24V AC |
| Backup Power | One 9-Volt Alkaline Battery (Not Included) |
| Programs | 3 Independent Programs |
| Compatible Valves | Standard 24V AC Solenoid Valves |
| Smart Upgrades | SMRT Logic & Climate Logic Compatible |
| MPN | RD900-EXT-COMPACT |
Get your classic multi-zone controller running smoothly.
Step 1: Mount the Enclosure
Secure the compact housing to a wall using the appropriate mounting hardware. Ensure you have access to a reliable 120V AC electrical source.
Step 2: Connect AC Power & Backup
Wire the controller's internal transformer to your 120V AC power supply. Install a fresh 9-volt alkaline battery to serve as a memory backup in the event of a power outage.
Step 3: Wire the Valves
Run multi-strand direct burial wire from your 24V AC valve manifolds to the controller. Connect the common wire to the 'VC' terminal and the individual valve wires to the numbered station terminals (1-9).
Step 4: Program via Dial
Use the straightforward dial interface to set the current time, date, watering days, and run times for each of your independent programs.
Does the Irritrol RD900-EXT-COMPACT require an electrical outlet?
Yes, the Irritrol RD900-EXT-COMPACT operates on standard 120V AC power using its built-in transformer. It is not a battery-powered controller, though it does require a 9-volt battery strictly to maintain your programming during power outages.
Professional installation is often recommended when hardwiring controllers directly to an AC power source.
Can I control the Rain Dial-R controller from my phone?
Yes, while it is a classic dial controller out of the box, it is fully compatible with Irritrol's SMRT Logic upgrade, which allows for complete mobile device programmability and remote control from your smartphone.
This upgrade gives you the modern convenience of Wi-Fi control without having to replace the reliable Rain Dial-R base unit.
What valves work with the Irritrol 9-Station controller?
This AC controller must be paired with standard 24V AC irrigation valves. It will not operate DC latching solenoids, so ensure you have the correct AC components installed in your manifold system.
You can easily connect up to 9 independent 24V AC valves to this controller.
How should I prepare my Irritrol RD900-EXT-COMPACT for spring watering?
Prepare the Irritrol RD900-EXT-COMPACT for spring by replacing the 9-volt backup alkaline battery, testing your AC valve connections, and using the water budgeting feature to run a scaled-back schedule for early-season moisture levels.
As the season warms up, simply adjust the water budget percentage upward to increase run times universally without reprogramming every station.
Please note the requirements for this AC-powered controller:
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