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What This Guide Helps With
This guide addresses situations where the Welch Allyn SureTemp Plus 692 thermometer gives inaccurate or inconsistent temperature readings. The focus is on external, easily verifiable causes—such as probe selection, probe cover integrity, device calibration, and user technique—before assuming internal sensor or electronics failure. The goal is to ensure accurate patient measurements while maintaining device safety.
Step-by-Step Troubleshooting
Verify Probe Type and Compatibility
- Ensure the correct probe is attached (oral, rectal, or axillary).
- Incompatible or damaged probes can produce inaccurate readings.
Inspect Probe Covers
- Check that probe covers are intact and properly seated.
- A torn, loose, or reused cover can cause false readings.
Check Device Calibration and Recent Verification
- Review the last calibration or verification date.
- If overdue, follow facility procedure for recalibration.
Test on Known Reference Temperature
- Use a calibration check source (e.g., water bath or calibration simulator) to verify accuracy.
- This helps isolate whether the issue is the thermometer or technique.
Check Battery / Power Status
- Low batteries can sometimes cause erratic readings.
- Replace batteries if low and retest.
Examine Probe for Physical Damage or Contamination
- Look for cracks, debris, or dried fluid on the probe tip.
- Clean per manufacturer instructions; do not immerse in liquid beyond specifications.
Ensure Proper Measurement Technique
- Follow correct placement and timing instructions per patient site.
- Patient movement or improper placement can skew readings.
If the Problem Persists
Common external causes have been ruled out. The device may have internal sensor or board issues.
- Remove the thermometer from service.
- Label as Out of Service.
- Send for manufacturer repair or bench evaluation.
Remember: stopping troubleshooting at this stage is proper clinical engineering practice.
Clinical Use Tip
Never rely on a thermometer giving inconsistent readings for patient care.
- Move the patient to another verified thermometer before continuing care.
- Always confirm unusual readings with a second device.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“Thermometer giving readings 1–2°C higher than expected on multiple patients.”
Cause
What was observed during troubleshooting.
Example:
“Probe covers intact; device cleaned; calibration overdue; low battery noted.”
Resolution
What action was taken.
Example:
“Replaced batteries, verified readings against calibration source. Out-of-spec readings persisted; device removed from service and labeled OOS for repair.”
Helpful Details to Include
- Probe type used (oral/rectal/axillary)
- Probe cover integrity
- Battery level
- Calibration check results
- Temperature readings compared to reference source
- Device cleaning status
- Final device status (removed, repaired, returned to service)
Final Thought
Accurate patient temperature measurement is critical. Following a methodical, external-first troubleshooting process ensures patient safety, preserves device integrity, and allows proper escalation when internal repair is required. Proper documentation reinforces accountability and helps track device performance.
That is successful troubleshooting.