1. Introduction
This manual provides essential information for the safe and efficient use of your Garza Analog Thermostat Model 400611. This device is designed for manual temperature regulation in heating systems, offering a straightforward and reliable solution for maintaining desired room temperatures. Please read these instructions carefully before installation and operation.
2. Product Overview
The Garza Analog Thermostat is a simple, non-programmable device for controlling heating systems. It features a manual rotary wheel for temperature adjustment and connects via a 3-wire system.
Key Features:
- Analog thermostat with 3-wire connection.
- Adjustable temperature range from 10 °C to 30 °C.
- Manual regulation with a rotary wheel.
- Simple installation and operation.
- Compact and discreet design.
Product Components:
The thermostat consists of a main unit with a temperature dial and internal wiring terminals. Mounting screws are included for installation.


3. Safety Information
WARNING: Electrical installation should only be performed by a qualified electrician or competent person. Always disconnect power to the heating system at the main circuit breaker before attempting any wiring.
- Ensure the power supply is off before installation or maintenance.
- Do not expose the thermostat to water or excessive humidity.
- Do not open or attempt to repair the device yourself. Refer to qualified personnel.
- Keep out of reach of children.
4. Installation
The Garza Analog Thermostat is designed for wall mounting and requires a 3-wire connection to your heating system (e.g., boiler).
Tools Required:
- Screwdriver
- Wire strippers
- Drill (if mounting holes are not pre-existing)
Mounting the Thermostat:
- Choose a suitable location on an interior wall, away from direct sunlight, drafts, or heat sources (e.g., radiators, lamps). The recommended height is approximately 1.5 meters (5 feet) from the floor.
- Carefully separate the front cover from the back plate of the thermostat.
- Position the back plate on the wall and mark the drilling points through the mounting holes.
- Drill holes if necessary and insert wall plugs.
- Secure the back plate to the wall using the provided screws.

Wiring Instructions (3-Wire Connection):
Ensure power is disconnected before proceeding with wiring.
- Identify the three wires from your heating system: Live (L1), Neutral (N2), and Switched Live (3).
- Connect the Live wire (L1) to terminal 1 on the thermostat.
- Connect the Neutral wire (N2) to terminal 2 on the thermostat.
- Connect the Switched Live wire (3) to terminal 3 on the thermostat.
- Ensure all connections are secure and no bare wires are exposed.
- Carefully reattach the front cover to the back plate.

5. Operation
Once installed and powered, the Garza Analog Thermostat is ready for use. It operates by sensing the ambient room temperature and activating or deactivating the heating system to maintain the set temperature.
Setting the Temperature:
- Locate the large rotary dial on the front of the thermostat.
- Rotate the dial clockwise to increase the desired temperature or counter-clockwise to decrease it.
- The temperature scale, typically ranging from 10 °C to 30 °C, indicates the set point.
- The heating system will activate when the room temperature falls below the set point and deactivate when it rises above it.

6. Maintenance
The Garza Analog Thermostat requires minimal maintenance to ensure optimal performance.
- Cleaning: Wipe the exterior of the thermostat with a soft, dry cloth. Do not use abrasive cleaners, solvents, or wet cloths, as these can damage the device or cause electrical hazards.
- Inspection: Periodically check for any visible damage to the casing or wiring. If damage is observed, disconnect power and contact a qualified technician.
7. Troubleshooting
If you encounter issues with your thermostat, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Heating system not turning on. | No power to the thermostat. Temperature set too low. Wiring error. | Check circuit breaker. Increase the set temperature. Verify wiring connections (ensure power is off). |
| Heating system not turning off. | Temperature set too high. Thermostat sensor obstructed. Faulty thermostat. | Decrease the set temperature. Ensure no objects are blocking the thermostat's sensor. Contact support if problem persists. |
| Inaccurate temperature reading. | Thermostat location affected by drafts or heat sources. Sensor malfunction. | Relocate thermostat to a more stable environment. Contact support. |
If the problem persists after attempting these solutions, please contact customer support.
8. Specifications
| Feature | Specification |
|---|---|
| Brand | Garza |
| Model Number | 400611 |
| Product Dimensions (L x W x H) | 7.3 x 3.7 x 7.3 cm |
| Weight | 100 grams |
| Color | White |
| Style | Analog Thermostat |
| Material | Acrylonitrile Butadiene Styrene (ABS) |
| Power Type | Wired Electric |
| Temperature Range | 10 °C to 30 °C |
| Display Style | Analog |
| Mounting Type | Wall Mount |
| Connectivity Technology | 3-Wire |
| Batteries Required | No |

9. Warranty and Support
For warranty information and customer support, please refer to the documentation included with your product or visit the official Garza website. Keep your purchase receipt as proof of purchase.