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RESETTING THE HYDRAULIC CHECK VALVE

Your lift has been equipped with an automatic check valve designed to stop the descent of the lift if one side meets an obstruction while lowering. The valve may also “trip” if the lift is not properly synchronized and raised all the way up with little or no load. Generally, the check valve will reset automatically when you raise the lift; however, there may be instances where raising the lift does not produce enough hydraulic pressure to reset the valve (i.e. when the lift has a lighter vehicle or no vehicle at all on it). In this case, it may be necessary to perform the following procedure in order to lower the lift.

  1. Raise the lift all the way up until at least one side contacts the maximum height limits and the lift stops. Release the raise switch.
  2. Remove the red plastic cover and open the leveling valve all the way. (The leveling valve is located on the back of the power column, about 7 feet high.)
  3. Activate the raise switch to run the motor for only 1-2 seconds to pressurize the system and ensure both sides are at their maximum height. Release the raise switch.
  4. Close the leveling valve , it may take more effort to turn since the hydraulics are under higher pressure at this time.
  5. Press the air button to release the locks and depress the lowering lever to lower the lift.
THE HYDRAULIC CHECK VALVE SHOULD NOW BE RESET. THE SYNCHRONIZATION OF THE 2 POSTS SHOULD BE CHECKED AND THE LIFT SHOULD BE RESYNCHRONIZED IF NECESSARY.



SYNCHRONIZING THE LIFTING ARMS
(Valves close clockwise, open counter-clockwise)

NO VEHICLE SHOULD BE ON THE LIFT FOR THIS PROCEDURE!

If the lift is equipped with an adjustable FLOW CONTROL VALVE in the hydraulic line between the power unit and the column, ensure it is open all the way.

  • Check if both sides are completely lowered. If not, open the LEVELING VALVE (accessed from the back of the power column behind the red plastic cover) and press the LOWERING LEVER until both sides are down. Close the LEVELING VALVE.
  • Push the POWER BUTTON and raise the arms until both sides are just above the first lock position.
  • Press the LOWERING LEVER to lower the arms on the locks.
  • Open the LEVELING VALVE. Press the LOWERING VALVE again to ensure both side are resting on the locks. Check to make sure both sides are resting on the same relative lock position (They should be the same height above their relative base-plates. If not, start over.).
  • Press the POWER BUTTON for only 1 to 2 seconds. The slave side (post WITHOUT the power unit) should rise slightly. CLOSE THE LEVELING VALVE. (This puts a small amount of added pressure on the slave side so that it does not lag behind the master side.)
  • Push the power button and raise the lift. Listen to the locks “click” to determine if both sides lock within 1 second of each other with the slave side locking first. If you are not satisfied, repeat steps B - F, varying the time you run the motor in step F until you are satisfied.



FLOOR REQUIREMENTS

HT-12,000 2-POST - Check the condition of your floor. Concrete should be a minimum of 5” thick and have a strength of at least 4,000 psi. There should not be any cracks or seams within 8” of any base anchors. The installation location must not require a shim stack more than 1” high in order to plumb the column. You should also determine that the difference in the elevation of the two columns is no more than 2”. If concrete is fresh, it must cure for a minimum of 10 days.

HT-15,000 or 20,000 2-POST - Check the condition of your floor. Concrete should be a minimum of 8” thick and have a strength of at least 4,000 psi. There should not be any cracks or seams within 8” of any base anchors. The installation location must not require a shim stack more than 1” high in order to plumb the column. You should also determine that the difference in the elevation of the two columns is no more than 2”. If concrete is fresh, it must cure for a minimum of 10 days.

OPTIONS: If your floor does not meet this minimum requirements, contact us for installation options. Contact us for floor requirements for lifts not listed here.






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