MAINTENANCE Teledyne API Model 701 Zero Air Generator
6-6 01671H (DCN6051)
6.8 Servicing The Regenerative Dryer
It is unlikely that the Regenerative Dryer should ever need service. Should the
molecular sieve become contaminated by oil or other external contaminants, the dryer
will need to be cleaned and recharged. See Figure 6-1.
1. Turn off and unplug the M701, plug in and turn on again and remove any water in
bowl.
2. Allow the pressure to bleed to zero.
3. Remove the two pneumatic connections and the electrical connection from the
4-way manifold.
4. Remove the dryer from the chassis by undoing the four captive screws in the
scrubber base.
5. Remove the 4-way valve bracket from the upper manifold and let the valve hang
loose attached to the lower manifold.
6. Remove the three nuts on top of the upper manifold.
7. Remove the upper manifold.
8. Remove the two columns.
9. Remove the retainer pads from the two columns and dump the molecular sieve into
a suitable waste receptacle. (The molecular sieve is not toxic but it may be dusty so
you may want to wear a mask.)
10. Wipe out the inside of the columns with a clean, dry rag.
11. Examine the surface and ports in the upper and lower manifolds. If there is an
accumulation of dirt or corrosion, disassemble the manifolds and clean them. If not,
proceed with step 12.
12. Place one HW0000376 washer and then two new clean retainer pads in one end of
each column. Push the pads 1/8” into the column.
13. Pour new clean molecular sieve into each column, up to 1/4” from the top. Rap the
side gently, (with a screw-driver handle or similar) to settle the molecular sieve, and
then top up to the 1/4” mark again.
14. Place one HW0000376 washer and then one new clean retainer pad on top of the
molecular sieve. Push the pad 1/8” into the column.
15. Change the four o-rings in the circular grooves in the upper and lower manifolds.
16. Place the bottom of the columns (with two pads) in the circular grooves in the lower
manifold. Be sure that they really are in the grooves and not caught up on the edge.
17. Wipe the ends of the columns. These are the surfaces which seal against the
o-rings.