3M Bair Hugger 505 User manual

Warning: Electrical Shock Hazard. There are electrically live parts within the
warming unit when it is connected to a power source, even when the switches are
in the OFF or STANDBY position.
Please forward to Biomedical Engineering Department
Vorsicht: Gefährliche elektrische Spannung. In einem an das Stromnetz angeschlossenen
Wärmegerät stehen bestimmte elektrische Komponenten auch dann unter Strom, wenn
der Schalter auf AUS oder BEREITSCHAFTSMODUS geschaltet ist.
Bitte an die Abteilung für biomedizinische Technik weiterleiten
Mise en garde : Risque d’électrocution. Certaines pièces sont électriquement chargées
dans les appareils de réchauffement, lorsque ceux-ci sont connectés à une source
d’alimentation et ce, même si l’appareil est en position OFF (arrêt) ou STANDBY (attente).
A transmettre au Service d’ingénierie biomédicale
3
Bair Hugger™
Model 505 Warming Unit
Service Manual
Total Temperature Management™ System
UNITÉ DE GESTION DE TEMPÉRATURE BAIR HUGGER MODÈLE 505 SERVICE MANUEL
BAIR HUGGER MODELL 505 TEMPERATURMANAGEMENTGERÄT SERVICE GEBRAUCHSANLEITUNG
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Français 29
Deutsch 59
English 1
3
Bair Hugger
Model 505 Warming Unit
Service Manual
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Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Description of the Total Temperature Management™ System � � � � � � � � � � � � � � � � � � � � � � � � � � 1
Indications� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 1
Contraindications� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 1
Definition of Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Explanation of Signal Word Consequences � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
WARNINGS � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
CAUTIONS � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 4
NOTICES � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 5
Read Before Servicing Equipment � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 6
Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Cabinet Cleaning � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 7
Hose Replacement� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 7
Power Fuse Replacement � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 8
Control Board Fuse Replacement � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 9
Air Filter Replacement � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �11
Over Heat Alarm Testing � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �12
Over Heat Alarm Thermostat Adjustment� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 15
Normal Operating Temperature Testing � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �17
Normal Operating Temperature Adjustment � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 19
Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Call Technical Support for Replacement Parts � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 21
Technical Support and Customer Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
When You Call for Technical Support � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 22
In-Warranty Repair and Exchange USA � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 22
Worldwide � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 22
Returning Units for Service � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 23
Exploded Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
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Introduction
Description of the Total Temperature Management™ System
The 3MTM Bair HuggerTM brand Total Temperature
Management system consists of a Bair Hugger forced-air
temperature management unit (with available rolling stand and
sheet clip) and disposable components, including Bair Hugger
forced-air blankets, 3MTM Bair PawsTM patient warming gowns,
and the 3MTM 241TM blood/fluid warming set. You can use the
Model 505 temperature management unit in all clinical settings
including the operating room to provide patient temperature
management.
The Bair Hugger warming unit is attached to the blanket or
gown by means of a flexible hose. Warm air is generated in the
unit and flows through the hose and into the blanket or gown.
Depending on the model, the blanket or gown is placed either
around, over, or underneath the patient. Small perforations on
the blanket or gown allow the warm air to be dispersed over the
patient. For fluid warming applications, the Model 241 blood/
fluid warming set is inserted in the warming unit hose. When the
unit is turned ON and a temperature setting is selected, warm air
flows over the Model 241 tubing and warmed fluid exits from
the distal end of the tubing. For additional information on Bair
Hugger blankets, Bair Paws gowns, the 241 warming set, or other
accessories visit us online at bairhugger.com or bairpaws.com.
This manual describes how to service the Model 505 warming
unit, and includes maintenance instructions and specifications.
For information about using Bair Hugger blankets, the 241
blood/fluid warming set, or Bair Paws gowns with Bair Hugger
units, refer to the “Instructions for Use” included with each of
these disposable components.
Indications
The Bair Hugger temperature management system is intended
to prevent and treat hypothermia. In addition, the temperature
management system can be used to provide patient thermal
comfort when conditions exist that may cause patients to
become too warm or too cold. The temperature management
system can be used with adult and pediatric patients.
Contraindications
Do not apply heat to lower extremities during aortic
cross-clamping. Thermal injury may occur if heat is applied to
ischemic limbs.

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Definition of Symbols
ON/STANDBY
ON (used on isolation switch)
OFF (used on isolation switch)
ON/OFF push button switch
Temperature Control
An equipotentiality plug (grounded) conductor other than a
protective earth conductor or a neutral conductor, providing a direct
connection between electrical equipment and the potential
equalization busbar of the electrical installation.
Please consult IEC 60601-1; 2005 for requirements.
Fuse
CAUTION
Dangerous Voltage
Type BF Equipment (patient applied)
VAC
V
Voltage, Alternating Current (AC)
This system is subject to European WEEE Directive 2002/96/EC.
This product contains electrical and electronic components and must
not be disposed of using standard refuse collection. Please consult local
directives for disposal of electrical and electronic equipment.
Protective earth ground
No free hosing
Date of manufacture
Manufacturer
Consult instructions for use
Follow instructions for use

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Recycle to avoid environmental contamination. This product contains
recyclable parts. For information on recycling, please contact your
nearest 3M Service Center for advice.
Keep dry
Temperature limit
Explanation of Signal Word Consequences
warning:
Indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
caution:
Indicates a hazardous situation which, if not avoided, could
result in minor or moderate injury.
notice:
Indicates a situation which, if not avoided, could result in
property damage only.
WARNINGS
1. Do not leave patients with poor perfusion unmonitored
during prolonged warming therapy sessions. Thermal injury
may result.
2. The Bair Hugger temperature management unit has been
designed to operate safely ONLY with 3M Patient Warming
disposable components. Use with other products may cause
thermal injury. (To the full extent permitted by law, the
manufacturer and/or importer declines all responsibility
for thermal injury resulting from the unit being used in
conjunction with non-3M Patient Warming products.)
3. Do not warm patients with the temperature
management unit hose alone. Thermal injury may
result. Always connect the hose to a Bair Hugger
blanket or Bair Paws gown before providing therapy.
4. Do not place the non-perforated side of the blanket on
the patient. Thermal injury may result. Always place the
perforated side (the side with small holes) towards the
patient.
5. Do not continue temperature management therapy if the
Over-temp indicator light illuminates and the alarm sounds.
Thermal injury may result. Unplug the unit, and contact a
qualified service technician.

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6. Do not continue 241 blood/fluid warming therapy if the Over-temp indicator
light illuminates and the alarm sounds. Immediately stop fluid flow, and discard
the blood/fluid warming set. Unplug the temperature management unit, and
contact a qualified service technician.
7. Do not use a forced-air warming device over transdermal medication. Increased
drug delivery and patient injury or death may occur.
8. Do not allow the patient to lie on the warming unit hose or allow the hose to
directly contact the patient’s skin during patient warming; thermal injury may
result.
9. Reusable blankets made from woven fabric, or blankets without discrete, visible
holes, can cause the safety system of this unit to fail, which may result in serious
thermal injury. This warming unit has been designed to operate safely ONLY
with Bair Hugger blankets and Bair Paws gowns.
10. Do not connect a Bair Hugger blanket, 241 blood/fluid warmer, or Bair Paws
gown to the warming unit if it has been cut or damaged; thermal injury may
result.
11. Do not use a Bair Hugger blanket to transfer or move the patient; injury may
result.To reduce the risks associated with hazardous voltage and fire:
• keep power cord visible and accessible at all times. The plug on the power
cord serves as the disconnect device. The wall socket outlet shall be as close as
practical and shall be easily accessible.
• use only the power cord specified for this product and certified for the
country of use.
• do not allow the power cord to get wet.
• do not use the warming unit when it appears the warming unit, power cord
or any component is damaged. Contact 3M Patient Warming Technical
Support at 1-800-733-7775.
• this equipment must only be connected to a supply mains with protective
earth.
12. To reduce the risks associated with exposure to biohazards always perform the
decontamination procedure prior to returning the warmer for service and prior to
disposal.
13. Do not retain the patient using a warming blanket alone, as injury may result.
Use a draw, sheet safety strap, or other means to retain the patient.
14. Do not modify this equipment without authorization of the manufacturer.
15. To ground the Bair Hugger warming unit, only connect to receptacles marked
“Hospital Only,” “Hospital Grade,” or a reliable grounded outlet.
CAUTIONS
1. Except for specific blanket models, Bair Hugger blankets are not sterile and are all
intended for single patient use ONLY. Placing a sheet between the Bair Hugger
blanket and the patient does not prevent contamination of this product.
2. Monitor the temperature and cutaneous response of patients who are incapable of
reacting, communicating and/or who are without a sense of feeling every 10-20

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minutes or according to institutional protocol. Monitor
the patient’s vital signs regularly. Adjust air temperature or
discontinue therapy when the therapeutic goal is reached or
if vital sign instability occurs. Notify physician of vital sign
instability immediately.
3. Do not leave pediatric patients unattended during therapy.
4. Do not initiate temperature management therapy unless
the temperature management unit is free from mechanical
damage and is safely placed on a hard surface or securely
mounted. Otherwise, injury may result.
5. To prevent tipping, clamp the Model 775 temperature
management unit to an IV pole at a height that provides
stability. We recommend clamping the unit no higher than
44” (112 cm) on an IV pole with a minimum 28” (71 cm)
diameter wheelbase. Failure to do so may result in IV pole
tipping, catheter site trauma, and patient injury.
6. Electrical shock hazard. Do not disassemble the temperature
management unit unless you are a qualified service
technician. There are electrically live parts within the unit
when it is connected to a power source, even when the unit
is in Standby mode.
7. To reduce the risks associated with environmental
contamination follow applicable regulations when disposing
of this device or any of its electronic components.
NOTICES
1. The Bair Hugger temperature management unit meets
medical electronic interference requirements. If radio
frequency interference with other equipment should occur,
connect the unit to a different power source.
2. Federal law (USA) restricts this device to sale by or on the
order of a licensed healthcare professional.
3. To avoid Bair Hugger warming unit damage:
• do not immerse the Bair Hugger warming unit or
warming unit parts or accessories in any liquid or
subject them to any sterilization process.
• do not use solvents such as acetone or thinner to clean
the warming unit; avoid abrasive cleaners.
• clean warming unit exterior with soft cloth using plain
water or a mild, all-purpose or nonabrasive cleaner.

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Read Before Servicing Equipment
The repair, calibration, and servicing of the warming unit
requires the skill of a qualified medical equipment service
technician who is familiar with good practice for medical
device repair. If service is designated as not requiring
manufacturer’s attention, the technical information is provided
in this service manual or will be provided, on request, by 3M
Patient Warming
Refer to Service Manual
Perform all repairs and maintenance in accordance with the
instructions in this service manual.
Safety Inspection
Perform a safety inspection after making repairs to the
Bair Hugger warming unit and before returning the warming
unit to service. A safety inspection should include a test of the
operating temperatures (described in this service manual), the
Over Heat alarm system, as well as a leakage current test.
Proper Use and Maintenance
3M Patient Warming assumes no responsibility for the
reliability, performance, or safety of the equipment if:
• Modificationsorrepairsareperformedbynon-authorized
personnel.
• Theequipmentisusedinamannerotherthanthatdescribed
in the Operator’s or Service Manuals.
• Theequipmentisinstalledinanenvironmentthatdoesnot
meet the relevant grounding requirements.

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Service Procedures
Cabinet Cleaning
Tools/Equipment
Soft cloth, lightly dampened with water and mild detergent.
Method
1. Disconnect the warming unit from the power source.
2. Wipe the exterior of the warming unit clean.
CAUTION: Do not use a dripping wet cloth when cleaning the
warming unit. Moisture may seep into the electrical contacts
and damage the components. Also, do not use alcohol or other
solvents to clean the cabinet. Solvents may damage the labels and
other plastic parts.
Hose Replacement
Method
1. Press the tab on the blower outlet to release the existing
hose.
2. Attach the replacement hose by inserting the flange end at
a 45° angle in the grooved blower outlet, then snap the hose
into place. (See Figure 1.)
Figure 1. Attaching the
Replacement Hose
Insert flange into
groove and snap into
place
Press this
tab to
release
hose

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Power Fuse Replacement
The power fuses are located in the power entry module. A
spare fuse is located in the fuse carrier (see Figure 2).
Tools/Equipment
Phillips-head screwdriver
Small slotted screwdriver
Method
1. Disconnect the warming unit from the power source.
2. Remove the 2 Phillips-head screws that secure the cord
retainer. Remove the power cord.
3. Locate the fuse carrier in the center of the power entry
module (see Figure 2).
4. Use the small screwdriver to remove the fuse carrier from
the power entry module.
5. Remove the blown fuse(s) from the fuse carrier.
6. Place the new fuse(s) (as marked) into the fuse carrier.
CAUTION: Replace only with the fuse capacity and type that is
indicated on the adjacent label.
7. Replace the fuse carrier into the power entry module.
8. Reattach the power cord.
9. Replace the 2 Phillips-head screws to reattach the cord
retainer.
10. Reconnect the warming unit to the power source.
11. Record the maintenance action taken and the hours of
operation (read from the hour meter) in the Maintenance
Log section.
Power entry
module (see
detail)
Figure 2. Location
of Power Fuse

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Control Board Fuse Replacement
Control board fuses are located on the control board. (See
Figure 3.) The internal fuses on the Model 505 are for control
board functions only.
The power fuses are located in the power entry module.
Instructions for power fuse replacement can be found in the
Power Fuse Replacement section.
Tools/Equipment
Phillips-head screwdriver
Method
1. Disconnect the warming unit from the power source.
2. Turn the Model 505 unit over, so that the bottom panel is
facing up.
3. Using the Phillips-head screwdriver, remove the screw from
each of the 2 front feet (bumpers) and remove the feet.
4. Remove the Phillips-head screw from the center of the
upper rear panel.
5. Remove the 2 Phillips-head screws located under the bed
hooks on the upper rear panel. Turn the unit right side up.
6. Lift the top cover and unhook the front of the top cover
from the retainer bracket inside. The control panel is
located on the underside of the top cover. See Figure 3 for
location of the fuse.
7. Remove the fuse and replace with the new one.
CAUTION: Replace only with the fuse capacity and type that is
indicated on the adjacent label.

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Control Board Fuse Replacement
8. Hook the retainer bracket onto the front of the top cover.
9. Place the top cover back into position. Replace all screws.
NOTE: It may be necessary to remove the air filter to correctly
position the lower portion of the retainer bracket inside the
unit.
10. Reconnect the warming unit to the power source.
11. Record the maintenance action taken and the hours of
operation (read from the hour meter) in the Maintenance
Log section.
Figure 3. Location of
Control Board Fuse
Control board
fuse
Flip the top cover to access the
control board
Phillips-head screws
Retainer bracket
Retainer bracket
hooks into top cover
and is secured by
screws through two
front “feet”

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Air Filter Replacement
The air filter is mounted in the bottom of the warming unit
(See Figure 4).
Tools/Equipment
Phillips-head screwdriver
Service Frequency
Every 12 months or 500 hours of use.
Method
1. Disconnect the warming unit from the power source.
2. Remove the M6 x 25 pan-head screw on the bottom of the
unit. The filter should slide out easily.
3. Record the hour meter reading and date on the new air
filter label. The hour meter is located in the lower left
corner of the top warning label (see Figure 4).
4. Slide the new filter into the base of the unit.
5. Replace the M6 x 25 pan-head screw on the bottom of the
unit.
6. Reconnect the warming unit to the power source.
7. Record the hour meter reading and maintenance action
taken in the Maintenance Log section.
Figure 4. Location
of Air Filter and
Hour Meter
Air filter
Hour meter

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Tools/Equipment
Phillips-head screwdriver
• Useacalibratedtemperaturemeterthatcanacceptamale
subminiature connector and read a K style thermocouple
(e.g., a Fluke Model 52 K/J Thermometer).
• Iftheconnectordoesnotfityourmeter,youcanremove
the provided connector and attach a connector that fits your
meter.
Over Heat Alarm Testing
WARNING: Perform all testing and adjustments of warming unit
temperature with Temperature Test Unit Model 22110. 3M
Patient Warming assumes no responsibility for the reliability,
safety, or performance of the Bair Hugger system if warming unit
temperature testing or adjustments are made in any other manner
than that described here. Improper measurement or adjustment of
the warming unit’s over heat alarm setting could result in patient
exposure to temperatures outside of the indicated range, and may
lead to patient injury.
NOTE: The Temperature Test Unit Model 22110 is designed to
simulate the operating characteristics of Bair Hugger blankets and
Bair Paws gowns when used with Bair Hugger warming units; use
of the temperature test device with any other warming system may
result in imprecise readings.
The Temperature Test Unit Model 22110 temperature readings are
taken from a calibrated temperature meter.
Service Frequency
12-month intervals or 500 hours of use

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Over Heat Alarm Testing
Method
The Over Heat alarm test panel is located on the back panel of
the Model 505 (see Figure 5).
1. Insert the open hose end from the warming unit in the port
on the Temperature Test Unit (see Figure 6).
NOTE: Do not block the rear air vents on the test device.
2. Connect the warming unit to the power source and press
the system ON button.
NOTE: The temperature setting will not affect the Over Heat
test.
3. Using the Phillips-head screwdriver, remove the screw on
the alarm test panel. The unit will go into an over heat
condition when the test panel is loose.
4. When the over heat alarm activates both visually and
audibly, note the maximum temperature achieved. Let the
alarm operate for at least 1 minute or until the temperature
test kit read-out is approximately 38°C (100°F), then press
Standby; the alarm should also turn off. The alarm and
manual reset constitutes one cycle. Pressing ON again will
restart the overheat cycle.
NOTE: If the alarm does not turn off, allow the unit to alarm for
1 more minute before turning the warming unit to STANDBY,
then ON again.
Figure 5. Location of Over Heat
Alarm Test Panel
Test
panel
Port
Hose
Figure 6. Temperature Test Unit Model 22110

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Over Heat Alarm Testing
5. Allow the warming unit to cycle 2 times more after the first
satisfactory reading. When the alarm activates, note the
alarm temperature read-out from the test kit. See Table 1
for specified limits.
NOTE: The first over heat cycle temperature may be slightly
higher when started from a cold start.
6. If the results of the test did not meet specified limits,
adjust the over heat thermostat. See the Over Heat Alarm
Thermostat Adjustment section.
7. If the results of the test did meet specified limits, turn the
warming unit to STANDBY, and disconnect the warming
unit from the power source.
8. Remove the hose end from the port on the Temperature
Test Unit.
9. Retighten the screw on the over heat alarm test panel.
10. Record the maintenance action taken and hours of
operation (read from the hour meter) in the Maintenance
Log section.
Table 1. Over Heat Specification
High Temperature Thermostat Model 505
The thermostat interrupts power to the heater and activates
the alarm at a preset high temperature of 53° ± 3°C
(127.4° ± 5.4°F) or less at the end of the hose, as determined
by the Temperature Test Unit Model 22110.

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Over Heat Alarm Thermostat Adjustment
WARNING: Improper adjustment of the warming unit’s over heat
alarm setpoint could result in patient exposure to temperatures
outside of the indicated range, and may lead to patient injury.
• Closelyfollowinstructionsforthermostatadjustment.
• Dangerous voltages are present at the terminals of the
thermostat.
• AlwaysuseaTemperatureTestUnitModel22110toverify
output temperatures.
• TheTemperatureTestUnitModel22110doesnotneedtobe
calibrated. The meter it is connected to must be calibrated.
Follow the calibration instructions in the meter service manual or
follow standard facility calibration schedules.
• Whenindoubt,contact3MPatientWarmingTechnicalSupport
for assistance in temperature adjustment.
Tools/Equipment
• TemperatureTestKitModel22110
• Smallslottedscrewdriver
• Phillips-headscrewdriver
Method
1. Insert the open hose end from the warming unit in the port
on the temperature test device.
NOTE: Do not block the rear air vents on the test device.
2. Connect the warming unit to the power source and turn the
warming unit power ON.
NOTE: The temperature setting will not affect the over heat
adjustment.
3. Using the Phillips-head screwdriver, remove the screw on
the alarm test panel. Lift and remove the panel.

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Over Heat Alarm Thermostat Adjustment
4. Locate the over heat adjustment thermostat (see Figure 7).
NOTE: Adjustment of the over heat alarm thermostat
is most easily done while the temperature read-out is
climbing.
5. Use a small slotted screwdriver to adjust the thermostat.
• Ifthetestedalarmtemperaturewasbelow the
specified limits, turn the screwdriver CLOCKWISE to
increase the alarm temperature.
• Ifthetestedalarmtemperaturewasabove
specified limits, turn the screwdriver
COUNTERCLOCKWISE to lower the alarm
temperature.
6. Fine-tune the adjustment until the warming unit alarms at
the specified temperature.
7. Manually turn the warming unit to STANDBY, then
ON again. This manual reset constitutes one cycle.
8. Retest the alarm temperature to verify correct adjustment at
least 2 times. Allow the warming unit to cycle before each
test.
9. When the warming unit alarm setting is within the
specified limit, turn the warming unit to STANDBY and
disconnect it from the power source.
10. Remove the hose end from the temperature test device.
11. Replace the over heat alarm test panel. Resecure the screw.
12. Record the maintenance action taken and the hours of
operation (read from the hour meter) in the Maintenance
Log section.
Figure 7. Location of Over
Heat Alarm Thermostat
Over heat alarm
thermostat access
(detail)