3M
TM
Ranger
TM
Blood/Fluid and Irrigation Warming Systems
English
14
Check the 3M
TM
Ranger
TM
system website to ensure you have the most recent version of this document.
www.rangerfluidwarming.com reorder #202524A
t
eSting
the
o
veR
-
tempeRAtURe
A
leRt
p
ointS
(43°C [±1]
And
46°C [+3, -2])
The over-temperature alert test causes the Ranger warming unit to go into an over-temperature test
mode by manually overriding the primary control system and engaging the heaters. The Ranger
warming system is very responsive to heater input; therefore the test procedures are technique
sensitive. Read instructions thoroughly before beginning these tests.
The first alert point at 43°C (±1) notifies user to the rise in temperature (see step 7). At the
46°C (+3, -2) secondary alert set point, the unit cuts power to the heaters (see step 8). Please note that
due to the heaters’ rapid response, you may see temperature readings drift within the range of 44-
49°C.
7. Loosen the over-temperature screw on
the bottom of the Ranger warming unit
(see Fig. 3). Listen for a slight click as the
microswitch opens. Loosen 1/2 turn more.
This unit is now in over-temperature test
mode, and the temperature output of the
unit should begin to rise. When the Ranger
display reads 43°C, verify that an audible
alert sounds, the alert light illuminates, and
the display alternately flashes “HI” and the
plate temperature.
8. Listen for the power relay to click at 46°C (+3, -2) (you can feel the click when holding the lower
left corner of the unit as you face the front display). The click signifies the secondary alert trip
point and signals that power to the heaters has been shut off. The over-temperature alert sounds,
the alarm light illuminates, and the alphanumeric display alternately reads “HI” and the plate
temperature. Watch the thermocouple temperature monitor to determine the unit’s peak
temperature output (less than 1 minute). The temperature reading on the monitor should peak
at 46°C (+3, -2).
note
:
If the temperature displayed on the thermocouple monitor exceeds 49°C during the test, tighten
the over-temperature test screw on the bottom of the Ranger warming unit, unplug it, and run
cold fluids through the cassette. This returns the unit to normal operating temperature. Call 3M
Patient Warming technical support.
9. The secondary alert is designed to latch. Verify this feature by momentarily turning off the
power switch, then turning it on again. The Ranger warming unit should continue alerting
throughout this sequence.
10. Securely tighten the over-temperature screw, turn off the Ranger warming unit, and unplug the
unit. Once power is cut to the Ranger warming unit, the alert will cease. The unit is ready to
return to service after it cools to normal operating temperature (approximately 20-30 minutes).
Fig. 3: Ranger warming unit over-temperature screw
Over-temperature
screw
M
od
el
2
45
