Leslie Controls NYC Heat Exchanger - Manual (Page 16)

Page 16 of 25
SOLENOID VALVES
(Ref ASCO Form number V6297R2)
See ASCO solenoid instruction set for Installation,
Operation and Maintenance Instructions.
RECIRCULATION PUMPS
(Ref Bell and Gossett manual P81884 Rev C)
1. Reference instructions for repairing mechanical
seal.
2. Close valves on the suction and discharge sides of
pump.
3. Loosen conduit box cover screw and remove
cover.
4. Disconnect electrical supply lines.
5. Remove flange bolts and nuts and then remove
pump from piping.
6. Loosen four cap screws that hold motor housing
to pump body. Remove these screws and remove
the housing from pump body.
7. Place pump on a flat work surface and insert a
screwdriver into one of endplate ventilation slots
until it engages a rotor cooling fin. While holding
rotor with screwdriver, turn impeller clockwise.
Note that impeller is molded around a metal hub
with a left hand thread. Remove impeller from
shaft.
8. Remove seal assembly from shaft by sliding it off
shaft sleeve.
9. Clean seal seat with a clean rag and inspect for
grooving or cracks. If it shows no grooving or
cracks, it may be cleaned and reused.
10. If seal seat is to be replaced, face plate must be
removed from motor housing. Remove it by
gently prying it away from housing.
11. Remove seal seat and cup. Lubricate cup with
soapy water and install new parts in face plate
recess. Reposition face plate on motor housing.
Gently tap face plate evenly around its diameter
to drive it into recess provided in motor housing.
12. Clean shaft and sleeve before installing new seal.
13. Slide new carbon seal head onto shaft sleeve until
it contacts seal seat. Slide new “O-Ring” and
back-up ring along shaft sleeve until they fit
inside counter bore in seal head. Place seal spring
between back-up ring and seal cage while
positioning seal cage flush with end of sleeve.
Place small end of spring against back-up ring.
Three driving legs of seal cage should engage
three slots on seal head. While holding rotor
assembly with screwdriver, thread impeller onto
shaft in a counter clockwise direction. Tighten
impeller with light hand pressure. Take care to
avoid bending a rotor cooling fin or damaging
shaft sleeve.
14. Clean recess in pump body and install a new body
gasket.
15. Install pump in body and secure with four
capscrews. Apply torque evenly in a criss cross
pattern in 40 in-lb to a torque of 80 in-lb.
WARNING!
Pressure may be present in the pump body. Loosening
flange bolts and shifting pump assembly slightly to
allow pressurized water to escape can relieve this
pressure. Failure to follow these instructions could
result in serious personal injury or death
WARNING!
Be certain electrical power is not present at motor leads
before continuing. Failure to follow these instructions
could result in serious personal injury or death