Type YF4GNC: Rod thermostats, temperature control


-Equipment requesting a very strong resistance to water ingress. The transparent cover allows to visualize the set point and the 2 pilot lights

These liquid expansion rod thermostats can be installed inside pockets as immersion thermostats in pipelines and containers, and for monitoring temperature in air ducts, in usual industrial applications and environments. (Not suitable for hazardous areas).


Housing: Protection class IP 66 upon EN 60529 (waterproof spray water under high pressure and sea splashes, totally dust tight). Body in black PA66, fiber glass reinforced. The transparent polycarbonate cover can be unscrewed by hand, but it is also possible to use a hook spanner. Mechanical impact resistance : IK10. High UV resistance.

Set point adjustment:  By °C printed knob. All types have an adjustable rotation limit system located  inside the knob that allows reducing the set point adjustment span. °F printed knobs available as an option.

Action: Temperature control. On-Off action.

Sensing element: Liquid expansion bulb and capillary inside nickel plated brass pocket.  Thread ½” BSPT. Tube outside diameter 10mm.  Located at the bottom of the housing, 2 screws are used to secure standard pockets. (See the compatible stainless steel and brass pockets range in the accessories section)

Pilot lights: One pilot light visualizes the thermostat contact output position. The other visualizes the power supply input. Phase and line electrical supply is mandatory for these pilot lights.

Set point adjustment ranges:  4-40°C (40-105°F); 0-60°C (32-140°F); 0-90°C (32-195°F); 30-90°C (85-195°F); 30-110°C (85-230°F).

Cable input and output: Two M20 cable glands, built-in black PA66.

Electrical connections:  Inside, on screw terminal connection block. It is possible to connect 2 wires 1.5mm² on each terminal.

Earthing:  Internal screw terminal.

Mounting: By the pocket thread or by 2 legs with holes for screws dia. 4 to 5 mm, 114 mm distance. 

Identification: Identification label on backside.

Contact: SPDT

Electrical rating, resistive loads:

 –Open on temperature rise contact (C-1)

16A 250V, 50 ~60Hz: >100000 cycles,

20A 250V, 50 ~60Hz: ≥ 50000 cycles,

10A 400V, 50 ~60Hz: ≥ 50000 cycles.

-Close on temperature rise contact (C-2): 6A 250V 50 ~60Hz: >100000 cycles

Electrical rating, inductive loads:

 –Open on temperature rise contact (C-1): 2.6A 250V, 50 ~60Hz: >100000 cycles

-Close on temperature rise contact (C-2):0.6A 250V 50 ~60Hz: >100000 cycles. 

Minimum Storage temperature: -35°C (-30°F)

Maximum ambient temperature: 60°C (140°F)

For more technical information ask 8G thermostat technical data sheet.



2D&3D Drawing

Main references

Temperature range

°C (°F)

References  Pocket length

(L, mm)

Temperature sensing length



°C (°F)

Max temperature on rod °C (°F)
4-40°C (40-105°F) YF4GNC04040231ZJ 230 140 1±0.5°C (1,8±1°F)

70°C (158°F)

4-40°C (40-105°F)

YF4GNC04040301ZJ 300 140 1±0.5°C (1,8±1°F) 70°C (158°F)
4-40°C (40-105°F) YF4GNC04040451ZJ 450 140 1±0.5°C (1,8±1°F)

70°C (158°F)

4-40°C (40-105°F)

YF4GNC04040601ZJ 600 140 1±0.5°C (1,8±1°F) 70°C (158°F)
0-60°C (32-140°F) YF4GNC00060231ZJ 230 87 2.5±1°C (4,5±1,8°F)

80°C (176°F)

0-60°C (32-140°F)

YF4GNC00060301ZJ 300 87 2.5±1°C (4,5±1,8°F) 80°C (176°F)
0-60°C (32-140°F) YF4GNC00060451ZJ 450 87 2.5±1°C (4,5±1,8°F)

80°C (176°F)

0-60°C (32-140°F)

YF4GNC00060601ZJ 600 87 2.5±1°C (4,5±1,8°F) 80°C (176°F)
0-90°C (32-195°F) YF4GNC00090231ZJ 230 87 2.5±1°C (4,5±1,8°F)

120°C (250°F)

0-90°C (32-195°F)

YF4GNC00090301ZJ 300 87 2.5±1°C (4,5±1,8°F) 120°C (250°F)
0-90°C (32-195°F) YF4GNC00090451ZJ 450 87 2.5±1°C (4,5±1,8°F) 120°C (250°F)
0-90°C (32-195°F) YF4GNC00090601ZJ 600 87 2.5±1°C (4,5±1,8°F)

120°C (250°F)

30-90°C (85-195°F)

YF4GNC30090231ZJ 230 87 2.5±1°C (4,5±1,8°F) 120°C (250°F)
30-90°C (85-195°F) YF4GNC30090301ZJ 300 87 2.5±1°C (4,5±1,8°F)

120°C (250°F)

30-90°C (85-195°F)

YF4GNC30090451ZJ 450 87 2.5±1°C (4,5±1,8°F) 120°C (250°F)
30-90°C (85-195°F) YF4GNC30090601ZJ 600 87 2.5±1°C (4,5±1,8°F)

120°C (250°F)

30-110°C (85-230°F)

YF4GNC30110231ZJ 230 83 2.5±1°C (4,5±1,8°F) 140°C (284°F)
30-110°C (85-230°F) YF4GNC30110301ZJ 300 83 2.5±1°C (4,5±1,8°F)

140°C (284°F)

30-110°C (85-230°F)

YF4GNC30110451ZJ 450 83 2.5±1°C (4,5±1,8°F) 140°C (284°F)
30-110°C (85-230°F) YF4GNC30110601ZJ 600 83 2.5±1°C (4,5±1,8°F)

140°C (284°F)

°F printing: replace last character (J) by K