Midmark 622
Midmark · Model 622
Power height. Manual back with air spring assist. Foot control standard. Receptacle and rear storage pod standard features.
Key tips
- ·When no category-specific guidance fits, default to the manufacturer's own service manual and the general troubleshooting method in the Engineer's Guide.
- ·Run an incoming and annual electrical safety test regardless of how niche the device is.
Typical Failure Modes
Compiled for this model from its own documentation and established engineering knowledge for this equipment class - not from a verified service record. Confirm against the manufacturer's service manual.
Base Up/Down will not operate
HighSymptoms: No base movement in one or both directions from the foot control.
Root cause: Base up- or down-limit switch tripped, blown primary/transformer/base-motor fuse, base actuator, or foot control.
Base drifts down
MediumSymptoms: Table lowers on its own under load.
Root cause: Base actuator backdrive or internal wear.
Moves the wrong direction / noisy / slow
MediumSymptoms: Function reversed, rumble, or sluggish travel.
Root cause: Wiring/capacitor fault, worn actuator, or dry mechanism.
Manual back with air-spring assist will not hold
LowSymptoms: Backrest drops or is very heavy to raise.
Root cause: Worn air (gas) spring on the manual back.
Serviceable Parts & Consumables
Serviceable items for this model, compiled from its documentation and engineering knowledge for this equipment class. Service class and relative cost are estimates, not manufacturer figures; no part numbers are given. Confirm intervals and pricing against the manufacturer.
Base actuator
Class Major service partRel. cost $$$R&R Moderate
Foot control
Class Periodic replacementRel. cost $$R&R Fairly easy
Primary / transformer / base-motor fuses
Class Major service partRel. cost $R&R Fairly easy
Base up / down limit switch
Class Major service partRel. cost $R&R Moderate
Back air (gas) spring
Class Major service partRel. cost $R&R Moderate
| Part | Service class | Relative cost | R&R difficulty |
|---|---|---|---|
| Base actuator | Major service part | $$$ | Moderate |
| Foot control | Periodic replacement | $$ | Fairly easy |
| Primary / transformer / base-motor fuses | Major service part | $ | Fairly easy |
| Base up / down limit switch | Major service part | $ | Moderate |
| Back air (gas) spring | Major service part | $ | Moderate |
Relative cost: $ lowest · $$$$ highest service-part cost for this equipment class. Not a price.
PM Checklist
Preventive-maintenance tasks typical of this equipment class. Perform to the manufacturer's procedure and your facility's policy - this is general reference, not a schedule for this specific unit.
- ·Follow the manufacturer's PM schedule
- ·Perform incoming and annual electrical safety testing per facility biomedical program
Troubleshooting Approach
A starting sequence for this model, compiled from its documentation and engineering knowledge for this equipment class. Follow the manufacturer's service documentation for the actual procedure.
Symptom: No base Up or Down
- Check the primary fuses at the power inlet, the transformer fuse and the base-motor fuse.
- Confirm neither the up- nor down-limit switch is tripped.
- Test with a known-good foot control.
- Trace current flow per the manual's Base Up/Down diagram.
- Replace the actuator if power reaches it but it will not run.
Symptom: Base drifts down
- Confirm the load and how fast it settles.
- Check the base actuator for backdrive.
- Replace the base actuator.
- Confirm it holds at several heights.
- Re-check limit-switch function.
Technical Specs
- Height
- 18 to 37 inches
- Length
- 60 in
- Patient Weight Capacity
- 400 lbs
- Width
- 28 in
Typical Location
Where this class of equipment is typically deployed - general reference, not this unit's own placement record.
- Varies by device - check the unit's own manual for facility placement guidance
Documents & Manuals
Troubleshoot this device with Bio
Describe a symptom or error code. Bio answers from this device's own documented error codes, failure modes, parts, and guides.
Ask Bio