5
DETERMINE
THE SEAL SIZE
Cut away diagrams have been pr
ovided to illustrate the com-
ponents of the Series 90 Pump assemblies. The primary fea-
ture distinguishing between the A and AA type pumps is size.
Measure the diameter of the shaft sleeve to determine nominal
seal size. Series 90 Pumps have three nominal seal sizes:
1
/
2
",
3
/
4
" and 1
1
/
4
". Most components of the A and AA pump seals
are similar (but not interchangeable). All Series 90 seals,
except the 1
1
/
4
", require a spring retainer as part of the seal
assembly. Refer to these diagrams whenever seal replacement
becomes necessary.
REPLACEMENT
PROCEDURE
With the motor assembly r
emoved from the system, use the
following instructions to facilitate the replacement.
1. Use a strap wrench or rag to prevent the impeller from turn-
ing with one hand and loosen the impeller nut with the other.
2. Lift the spring retainer (not found in the 1
1
/
4
" seal assem-
bly) and the seal spring from the shaft. Remove the com-
pression ring from the seal collar by inserting a small
screwdriver underneath the ring and carefully applying an
upward force.
NOTE:
Bell & Gossett seal assemblies consist of a stationary
seal insert assembly and a rotating seal assembly. Each of
these components must be replaced when replacing the
mechanical seal. NEVER REPLACE INDIVIDUAL COMPO-
NENTS SEPARATELY.
3. Using a clean, lint free rag, remove any debris that may
have accumulated in the seal recess.
4. For the
1
/
2
" and
3
/
4
" seals, place the new retainer in the
face plate seal recess. Set the thin seat gasket in the
recess and set the seat insert atop the gasket. A ceramic
insert has a top side and bottom side. The bottom is identi-
fiable by its slightly recessed grooves. These grooves
should face downward toward the rubber gasket.
For the 1
1
/
4
" seals, set the seal insert into the elastomeric
seat cup. Lubricate the seat cup with soapy water and
set it into the face plate recess.
5. Lubricate the rubber seal collar with soapy water. The
entire rotating seal assembly, which includes a seal ring,
bellows and seal housing, is to be pushed onto the shaft
as one unit. Do not attempt to assemble the seal by plac-
ing the components on the shaft individually. The notches
in the collar should be aligned with the recesses found on
each side of the carbon ring.
6. Press the seal housing tightly against the upper end of
the rubber collar. A screwdriver can be used at several
points along its periphery to provide a tight and even fit.
Press with the screwdriver – dot not tap. Tapping on the
seal may break the ceramic or carbon insert.
7. Place the seal spring on the shaft and then the spring
retainer (except for the 1
1
/
4
" seal). Next, place the
impeller and lock washer on the shaft. Thread the
impeller nut onto the shaft and tighten according to:
3
/
8
"
nut to 8-12 ft. lbs.,
7
/
16
" nut to 17-22 ft. lbs., and
3
/
8
" cap-
screws to 10-14 ft. lbs. Do not overtighten.
8. Clean the pump body of excess debris. Place a new gas-
ket in the recess of the pump body; ensure that it sits
flush against the gasket surface.
9. Replace the motor assembly by inserting the impeller in
the pump body and evenly tighten the eight cap screws.
Refer to the TORQUE CHART on the back page.
10. Refer to the WIRING INSTRUCTIONS section in this
manual to properly configure all electrical connections.
11. Follow the OPERATIONAL INSTRUCTIONS in this manual
to 1) check the PH of the system water, 2) to check the
rotation of the pump and 3) to pressurize the system prior
to starting.
PUMP
BODY DIAGRAM – A Size
PUMP BODY DIAGRAM – AA Size
WARNING: HOT WATER HAZARD
When disassembling a gasketed joint, always use a
new gasket upon reassembly. NEVER RE-USE OLD GAS-
KETS. Failure to follow these instructions could result in
serious personal injury, death and/or property damage.
