The A108 from Ageon is a temperature controller suitable for differential control of pumps, fans and valves. It has two sensors and a relay output for activating circulation according to the temperature difference between the T1 and T2 sensor readings. The instrument contains two NTC-type temperature sensors with 1.5M cable length, and the relay output has 17A capacity for direct switching of loads.
In a solar system, the water pump is activated to send heated water from the collector back to the storage tank. For air destratification/circulation, the control output activates a high-level fan to keep an even temperature throughout the building layers, eliminating heat wasted at the top of a building.
Basic parameters allow setting of differential on and off temperature, with two independent settings for greater control of the output. Advanced parameters allow protection to be set, preventing damage to the system due to low/high temperatures.
Well suited to hot water temperature control (solar installations, swimming pools, hot tubs, and hot water systems), HVAC air destratification (recycling hot air in factories, warehouses, and agricultural buildings), and agriculture (greenhouses, and cooling grain stores to maintain differential).
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Technical Details
Power: 110 or 220 Vac. Maximum power: 4 VA
Pump relay output: 17 A / 250 Vac
Measuring range: -20 to +105°C. Resolution: 0.1°C from -20 to +105°C
Operating conditions: 0 to 40°C, 10-80% RH non-condensing
Dimensions (W x H x D): 93 x 37 x 73mm. Degree of protection of the front part: IP65
NTC sensors: IP68, Ø5mm / L=20mm, standard length 1.5m
Functions: Standby (control outputs off, display idle), Automatic/Manual control, Differential On/Off individual setpoints, Pump Delay (adjustable 0-20 mins), antifreeze and overheat protections, Pump timeout (adjustable in auto and manual), Indicator mode (read temperatures only), Alarms/Limits (high and low temperature), Sensor Calibration (adjustable offsets)
Frequently Asked Questions
Are the sensors supplied?
Yes — the 2 sensors come with the controller. They can also be extended with 2x 0.5mm cable.
How should the sensors be attached?
Use of a thermowell is recommended by the manufacturer, but many customers have successfully attached the probes directly to pipework and reservoirs — suitable if the surface has good thermal conductivity.
Does the controller remember all of the parameters when turned off?
Yes — all values are saved and the controller can be powered down for lengthy periods of time.
Can you set a low temperature threshold to limit operation in cold weather?
Yes — increase A1 (low-temperature reservoir alarm limit, t2, -50 to A2, default -50°C) to achieve a low temperature threshold.
Can you set a high temperature threshold to prevent overheating?
Yes — there is an ultimate maximum at which all control stops (SP, setpoint, default 40°C), plus a separate alarm value (A2, high-temperature reservoir alarm limit, A1 to 100°C, default 100°C).
Can the A108 be used for solar heated swimming pools?
Yes — we recommend lowering the SP (setpoint) to 30-35°C, and adjusting R0 and R1 values to 20°C differential on and 15°C differential off, fine-tuned for best performance.
Can you help with programming?
Yes — for a small charge of £20.00 we can pre-program the controller.
Industry Applications
- Solar Water Heating — activates circulation pumps based on collector vs storage tank temperature difference.
- HVAC Air Destratification — recycles trapped hot air in factories, warehouses, and agricultural buildings.
- Agriculture — greenhouse control and grain store cooling to maintain temperature differential.
Browse the full Ageon Black Line range of temperature and humidity controllers, or add the Ageon WebFi gateway for remote connectivity.
Ageon is a Brazilian company, established in 2001, which manufactures solutions in temperature controls and frequency inverters for the refrigeration, heating, air conditioning and industrial automation industries. The company has been awarded ISO9001 and produces equipment to international CE standards.