Bulb & Capillary Thermostat for -40 deg Ambient 1

[warrenelec]

Hello,

I need to find a bulb & capillary thermostat to control a heater in a hydraulic reservoir (to maintain about +60 degrees F). This will be used in a control box where the ambient temperature could go as low a -40 degrees F (military application). Does anyone know where to find a thermostat that can handle this low of an ambient temperature on the switching side? I understand that the switching sensitivity will change at low temps due to higher viscosities of the oil in the capillary, but I need to be sure that the switches will not fail at such low temperatures. All help is appreciated. Thanks!

Warren

 

[danw2]

A distributor catalog I have lists any number of United Electric capillary and bulb switches as rated for -40°F ambient:

- model 800 (indicating with scale) (pg 19 pdf)
- series 100 (pg 20 pdf)
- E/B117 (pg 22 pdf)
- EXP E/F12x series (pg 22 pdf)

statement for Model 800: Setpoint typically shifts
<1% range for a 50°F ambient temperature change.

http://www.lesman.com/downloads/s14_switches.pdf

temperature switches start on page 19

Dan