3M
3M Bair Hugger Model 505 Service Manual May 2013
Service Manual
33 Pages
Preview
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3 Bair Hugger™
Model 505 Warming Unit
Service 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 UNITÉ DE GESTION DE TEMPÉRATURE BAIR HUGGER MODÈLE 505 SERVICE MANUEL
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 BAIR HUGGER MODELL 505 TEMPERATURMANAGEMENTGERÄT SERVICE GEBRAUCHSANLEITUNG
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
To t a l Te m p e r a t u r e M a n a g e m e n t™ S y s t e m
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3 Bair Hugger
Model 505 Warming Unit
Service Manual
English 1
Français 29
Deutsch 59
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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:
caution:
notice:
Indicates a hazardous situation which, if not avoided, could result in death or serious injury. Indicates a hazardous situation which, if not avoided, could result in minor or moderate injury. 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:
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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
Press this tab to release hose
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Insert flange into groove and snap into place
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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.
Figure 2. Location of Power Fuse
Power entry module (see detail)
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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
Flip the top cover to access the control board Phillips-head screws
Control board fuse
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 Hour meter
Air filter
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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
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.
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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.
Figure 5. Location of Over Heat Alarm Test Panel
Figure 6. Temperature Test Unit Model 22110
Hose
Port
Test panel
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.
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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)
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Bair Hugger Model 505 Service Manual