Instructions / Assembly

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exit the ON variable. Press the UP and DOWN arrows simultaneously again to exit programming
mode. The display will revert to a steady display of the present temperature of the probe/sensor.
CAUTION: Do not program the controller to OFF > 170°F (77°C) as this
may damage the heating blanket, your vessel and/or your product.
A Quick Look at Programmable Control Functions:
OFF, Relay Off Temperature, possible values from -40F to +212F, this is the temperature at
which the controller will turn off the heating blanket. Please see CAUTION above.
On, Relay On Temperature, the temperature at which you want the blanket to start heating again.
Possible values from -40F to +212F
ASd, Anti-Short Cycle Delay, Powerblanket presets this to zero minutes. It is the time you want
the controller to wait BEFORE it does anything after power is applied to the controller (after you
plug it in or after the power comes back on in the case of a temporary power outage). ASd is
useful when running, for example, a cooling pump where a quick power outage or temperature
cycle will stall the compressor and it won’t safely restart until the pressure has equalized in the
system – which can take several minutes. For heating blankets, there is no reason to wait to
restart the system.
SF, Sensor Failure Operation, Powerblanket presets this to zero which has the effect of turning
off the heating blanket in the rare case of sensor failure. Should you decide you want the blanket
to run full power without temperature control if the sensor malfunctions, which Powerblanket
does not recommend, set it to one.
F or C, Temperature Units, the units can be switched from Fahrenheit to Celsius or back by
holding the UP and DOWN arrows simultaneously for 5 seconds. “UN” will start flashing on the
screen. Press MENU to access this variable, then use the UP and DOWN arrows to select F or C.
Press the UP and DOWN arrows again simultaneously to return to the main functions of the unit.
To change the values of any of these variables (except “F or C”), press MENU to enter
programming mode, then use the UP and DOWN arrows to scroll to the function you wish to
program. Once you reach the desired function, press MENU again to adjust that variable. The
present value of each function will be shown. Use the arrow buttons to select the new value then
press MENU again to make that the new value in memory. If the controller is left idle in
programming mode for 30 seconds, the controller will exit the programming mode and the value
will not be changed.
Other Controller Information:
NEMA/UL 4X – Watertight enclosure.
120VAC GHT2002J (A421AEC), 15 Amps max for heating blankets.
240VAC GHT2002J-240V (A421AEC), 10 Amps max for heating blankets.
More information via “A421 Series Electronic Temperature Controls with NEMA 1 or NEMA
4X Watertight Enclosures” also included with the GHT2002J controller.