The GL-30 is a differential temperature controller designed for solar heating systems, offering adjustable differential ranges, high‑limit protection, and optional freeze‑recirculation. It can drive pumps or fans directly and supports remote sensors up to 1000 ft away.
The manual includes detailed specifications, wiring diagrams, mounting instructions, adjustment procedures, and a troubleshooting section to help installers and users set up and maintain the controller safely.
| Input Power | 120 VAC or 240 VAC |
|---|---|
| Output Power | 1 HP @115 VAC, 2 HP @240 VAC |
| Differential Range | 8 °F to 24 °F adjustable |
| Accuracy | ±1 °F |
| Dimensions | 5.875" × 4.875" × 2.375" |
| Sensor Type | 10 kΩ thermistor @ 25 °C/77 °F |
The differential is adjustable from 8 °F to 24 °F using the control’s adjustment knob.
Move jumper J2 from the "OUT" position to the "IN" position to enable freeze protection.
The controller can be powered from either 120 VAC or 240 VAC (105‑130 VAC or 195‑250 VAC depending on the model).