Pneumatech PH Series - PHM Series Maintenance Schedule; PHM Desiccant Replacement

14 Pub. No. OM-A-10H REV. 7 — June 2006
Mufflers
Purge mufflers are installed to reduce the noise level. The
mufflers tend to plug up and increase back pressure over
time due to oil carryover and contaminants from
compressor, or due to desiccant dust at the initial start-up.
To eliminate back pressure, replace muffler after three
months, or when the back pressure increases in the
regenerating tower.
PHM MINI SERIES HEATLESS AIR DRYER
MAINTENANCE
General
Clean the exhaust mufflers. Replace mufflers if there is any
back pressure on the tower in the regeneration cycle.
No lubrication is required, or should be used on any of
the components.
Daily
1. Check auto drain on prefilter every shift.
2. Follow the start-up procedure.
Weekly
1. Check the shifting, purge and repressurization
operation.
2. Check the operating conditions; inlet pressure, inlet
temperature and the flow rate.
3. Check the moisture indicator. BLUE color indicates
DRY conditions. If the color is PINK, refer to the
Troubleshooting Guide on Page 21 for probable
cause. (Optional equipment.)
4. Check the purge mufflers for blockage. Possible
indication is back pressure on tower under
regeneration. Replace if necessary.
5. Check the pressure drop across prefilter and
afterfilter. Replace the elements if the pressure drop
exceeds 7 PSID.
Three Months
1. Check the prefilter and afterfilter elements for
excessive clogging or possible damage. Replace as
necessary.
2. Check outlet dewpoint conditions.
Twelve Months
1. Close the inlet and outlet valves on the dryer or
bypass the dryer and completely depressurize the
dryer system. Open and check visually; if desiccant
is contaminated with oil or broken, replace the
desiccant.
2. Inspect and clean the 4-way switching valve, purge
solenoid valve and shuttle valve. Repair or replace
as necessary.
Mufflers
Purge mufflers are installed to reduce the noise level. The
mufflers tend to plug up and increase back pressure over
time due to oil carryover and contaminants from
compressor, or due to desiccant dust at the initial start-up.
To eliminate back pressure, replace muffler after one
month operation and/or when back pressure increases to
5 PSIG in the regenerating tower.
Desiccant Replacement Procedure
Pneumatech uses Activated Alumina Grade A 1/8"
diameter for all standard PHM Mini Series Heatless
Regenerative Air Dryers.
Filling Procedure:
1. Make sure the dryer is depressurized.
2. Remove the upper and lower interconnecting pipe
and valves.
3. Remove the Desiccant retaining screens on both ends
of the desiccant chambers. Remove all desiccant.
4. Using a flash light, inspect the inside of each vessel
to be sure they are empty.
5. Install the bottom desiccant screens and make sure
they are secured tightly.
6. Begin filling the towers.
7. Install the top desiccant screens, and all of the
interconnecting pipe and valves.
8. Refer to the start-up procedure listed in the manual.
Disconnect power and depressurize unit
completely before starting maintenance
procedures.