Derale 16738 Installation Instructions

16738 Single Stage Electric Fan Thermostat
Please read these instructions completely before starting the installation.
The single stage electric fan thermostat will
control up to two electric fans with a
maximum amperage draw of 25 continuous
amps. This unit includes a 30-amp relay,
wiring harness and an air-conditioning
override circuit to activate the fan whenever
the AC is on. On vehicles without AC, this
lead can be used as a manual override. See
wiring instructions below.

Installation Instructions

Thank you for buying a Derale electric fan thermostat.
Bill of Materials
Wire Harness
Relay
Thermostat Switch
Brass Probe
Retaining Clip
Foam Pad
# 14 Metal Screw
Blue Ring Connector
Blue Butt Connector
Scotch-loc Connector
Relay/Wire Harness Installation
1. Mount the relay/wire harness in a
convenient location, taking into account
the probe placement and wire routing, be
sure to avoid any hot components.
2. Drill one 3/16" hole and use supplied #14
metal screw to mount relay/wire harness.
Thermostat Probe Installation
1. Thread brass probe on to thermostat
switch
2. Insert the probe/switch between the fins
of the radiator core, as close to the water
inlet as possible. Keep pushing the probe
through the radiator core until it is flush
against the radiator.
3. After inserting the probe/switch through
the radiator core, install foam pad and
clip on probe and push until tight.
Note: Placement of the probe can affect
turn-on temperature. If you would like to
change the activation temperature, try
moving the probe/switch to a different
location on radiator.
Quantity
1
1
1
1
1
1
1
1
3
1