Introduction

1.1About this Manual

This manual is intended for qualified service personnel who will perform maintenance and servicing on the Fisher & Paykel Healthcare MR850 Respiratory Humidifier. This manual covers the product specifications, includes a maintenance schedule, and provides the necessary information required for servicing.

NOTE: Some software may not be available in your country. Refer to your local Fisher & Paykel Healthcare representative for the appropriate software version. Maintenance procedures should be carried out at regular intervals (as recommended in the maintenance schedule), to ensure that the humidifier and its accessories are working correctly.

If a fault should occur with the humidifier, follow the troubleshooting guide (section 6) in order to find the most likely cause. If the unit requires servicing, make sure the servicing procedures are followed in order to prevent damage to the humidifier. After service, or as part of the maintenance schedule, a humidifier performance check should be completed.

Due to the nature of the electronics contained within this humidifier, it is not recommended that the printed circuit boards be serviced at component level. Instead, if the PCBs are found to be malfunctioning, they should be replaced.

1.2

Glossary

 

 

Chamber

Device that allows gas to be to be heated and humidified by passing it

 

 

over heated water.

 

Temperature / Flow

Sensor assembly for measuring temperature and flow of respiratory

 

Probe

 

gases traveling through the breathing circuit. Consists of a chamber

 

 

 

and airway probe.

 

Airway Probe

Sensor assembly for measuring gas temperature at the end of the

 

 

 

inspiratory limb.

 

Chamber Probe

Sensor assembly for measuring gas flow and temperature at the

 

 

 

outlet of the humidification chamber.

 

Thermistor

A temperature sensitive resistor placed inside the chamber and

 

 

 

airway probes.

 

Chamber Set Point

The temperature that the humidifier attempts to maintain at the

 

 

 

chamber probe port.

 

Airway Set Point

The temperature that the humidifier attempts to maintain at the airway

 

 

probe port.

 

Heater Wire Adaptor

Electrical connector between the breathing circuit and the humidifier.

 

Breathing Circuit

Tubing that carries respiratory gases to and from the patient.

 

Dual Heated Breathing

A breathing circuit that is heated by means of heater wires, in both the

Circuit

 

expiratory and inspiratory limbs.

 

Single Heated

A breathing circuit that is heated by means of a heater wire, in only

 

Breathing Circuit

the inspiratory limb.

 

PCB

 

Printed Circuit Board.

 

Heater Wire

Wire inside the breathing circuit which heats the respiratory gases.

 

Inspiratory Limb

The section of the breathing circuit that takes the inspired gases to

 

 

 

the patient.

 

 

MR850 Technical Manual * Revision J * Issued November 2005 * Ref. 185041340 (185041713 internal)

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