The Davies Craig universal digital thermatic switch can be used to switch cooling fans or electric...The Davies Craig universal digital thermatic switch can be used to switch cooling fans or electric water pumps on and off at user settable coolant temperatures. The switch has an adjustable temperature range of 40-110 deg C and is settable by a button on the front of the unit. If being used with a twin fan set up the unit provides a 10 second delay between the first and second fans starting up.
-- Automatically switches fans or EWP at a pre-determined temperature
-- Switching temperature can be easily selected on the unit
-- Temperature sensor options for different applications
-- Kit includes all sensors and wiring necessary for installation
The digital thermatic EWP / Fan switch kits are available with different sensor options, probe type or probe and thermatic sensor. The probe can either be placed directly in the cooling system via the top radiator hose or it can be fitted between the fins of the radiator for a simpler fitting solution. The thermatic (coolant temperature) sensor is designed to screw into a waterway in the engine or into the radiator or alternatively in a coolant hose using a separately available adaptor.
Please note if this switch is being used for an electronic water pump it will only switch the pump on and off and will not control the pump speed. We recommend the Davies Craig EWP / Digital fan controller for this.
Kit contents - Switch Unit, Mount Kit, Scotch Lock, Ring Terminal, Self Tapping Screws, Wiring Connector, probe sensor or probe and thermatic sensors.
Dimensions - 95 x 65 x 56mm
Suitable for 12v or 24v operation. Please note: Kit sold in 12 volt configuration, for 24 volt application, you will need to change the two relays with 24 volt units which are not supplied in the kit.
Davies Craig Fan Switch / Digital Thermatic EWP - Cooling SystemFree delivery in 1–3 days£42.00Visit shop →
Product Information
Full details
The Davies Craig Digital Thermatic Switch is designed for automotive enthusiasts and DIY mechanics seeking precise control over their engine's cooling system. Its key benefit is automatically activating cooling fans or electric water pumps at user-defined temperatures, ensuring optimal engine performance and preventing overheating. A caveat to note is that while it controls the on/off function of electric water pumps, it does not manage pump speed; for speed control, a dedicated controller is recommended. This versatile switch offers an adjustable temperature range, selectable via a front-mounted button, and includes multiple sensor options for varied installation needs.
All features
Model Part Number
444
Brand
Davies Craig
Extended Product Information
FAQs
Can this switch control the speed of my electric water pump?
No, the Davies Craig Digital Thermatic Switch is designed to control the on/off function of electric water pumps only. For speed control, a dedicated controller like the Davies Craig EWP/Digital Fan Controller is recommended.
What is the adjustable temperature range of the switch?
The switch features an adjustable temperature range of 40°C to 110°C, which can be set using the button on the front of the unit.
Do I need to buy separate sensors?
No, the kit includes all necessary sensors and wiring required for installation. Different sensor options are available depending on your specific application needs.
How do I install the temperature probe?
The probe sensor can be placed directly in the cooling system via the top radiator hose or fitted between the fins of the radiator. The thermatic sensor screws into a waterway in the engine, radiator, or a coolant hose using an appropriate adapter.
Can this be used in a 24-volt vehicle?
Yes, it is suitable for 24v operation. However, you will need to replace the two supplied 12v relays with 24v compatible units, which are not included in the kit.
What are the dimensions of the switch unit?
The dimensions of the switch unit are 95mm (width) x 65mm (height) x 56mm (depth).
What is included in the kit?
The kit includes the Switch Unit, Mount Kit, Scotch Lock connectors, Ring Terminal, Self-Tapping Screws, Wiring Connector, and the selected probe sensor or probe and thermatic sensors.
Troubleshooting
Cooling fan/pump does not activate
Verify power supply to the switch. Check all wiring connections for security and correct polarity. Ensure the set temperature is below the current coolant temperature. Test the fan/pump directly with the vehicle's power source.
Switch not holding set temperature
Ensure the unit is securely wired and has a stable power source. If issues persist, the switch unit may need replacement.
Incorrect activation temperature
Recalibrate the temperature setting. Ensure the sensor is properly installed and making good contact with the coolant or airflow. Check sensor wiring for damage.
Fan delay not functioning
Confirm the unit is wired for a twin fan setup and that both fans are connected. Check the relays for proper operation. Ensure the correct fan is connected to the designated output.
Pros and Cons
Pros
Offers precise control over cooling system activation.
Flexible installation with multiple sensor options.
Adjustable temperature settings for tailored performance.
Includes all necessary components for a straightforward installation.
Suitable for both 12v and 24v vehicles (with 24v relay modification).
Cons
Does not control the speed of electric water pumps, only on/off.
Requires modification for 24v operation (relays not included).
Probe sensor placement requires careful consideration for accuracy.
Setup, Compatibility & Care
Setup:
Determine the best sensor location: either directly in the top radiator hose (probe sensor), between radiator fins, or screwed into an engine waterway/radiator (thermatic sensor).
Install the chosen sensor securely.
Wire the switch unit according to the provided diagram, connecting it to the power source, fans, and/or electric water pump.
Mount the switch unit in a suitable location within the engine bay.
Set the desired activation temperature using the button on the front of the unit.
Compatibility:
Operates with 12v systems directly.
Compatible with 24v systems by replacing the two supplied relays with 24v equivalents (not included).
Suitable for use with electric cooling fans and electric water pumps.
Care:
Regularly inspect sensor connections for corrosion or damage.
Keep the switch unit clean and free from excessive dirt or moisture.