Weil-McLain WM97+100 Manual page 120

WM97+ Series 2
Cleaning heat exchanger flue side, 110
Handle the cover plate/burner assembly carefully to
avoid damage to the components or refractory. Place
the assembly on a clean, flat surface.
Inspect refractory and replace if damaged
1. See Figure 125, page 121 part C.
a. Inspect the refractory to make sure it is intact, with no
visible damage.
b. If the refractory must be replaced, use a wide-blade putty
knife to gently pry the refractory from the heat exchanger
cover plate. The refractory is attached with silicone ad-
hesive and should separate with a little pressure on the
putty knife.
DO NOT gouge or crack the refractory. The refrac-
tory is made of ceramic fiber materials. Read the ce-
ramic fiber WARNING on page 100 before handling
or disposing of ceramic fiber materials.
c. When replacing the refractory, apply a ring of silicone
adhesive on the cover plate. Place the refractory onto the
cover plate. Before handling the assembly, allow the adhe-
sive to set enough that the refractory is firmly held in place.
Inspect and clean the heat exchanger
1. Access the heat exchanger interior by following the previous
instructions. Remove and inspect the heat exchanger cover
plate gasket. Replace if necessary.
2. See Figure 125, page 121 part E.
3. Use a strong light to visually inspect the interior of the heat
exchanger. Make sure the flueways (tubes) are clear and un-
obstructed.
4. Use a vacuum cleaner to remove any accumulation on the
heating surfaces. This includes removing any pieces of refrac-
tory than may have dropped into the exchanger.
DO NOT use any solvent when cleaning the ex-
changer.
5. If the vacuum cleaner is unable to clean completely, wash the
heating surfaces with clean, warm water.
a. Place a bucket under the boiler condensate drain con-
nection.
b. Loosen and move the condensate bracket, then loosen the
condensate trap upper nut and slide the trap off of the
drain connection. (See Figure 74, page 65 for reference.)
c. Spray water into the heat exchanger and tubes to remove
sediment. Collect water in the bucket below.
6. Inspect the heat exchanger cover plate gasket. Replace if is
damaged in any way.
Reinstall components
1. See Figure 125, page 121 for reference.
2. Clean cover plate. Ensure cover plate burner sealing surface is
clean and had no remains of old gasket are present.
3. Reinstall the burner (item 9) and burner gasket (item 10) on
the cover plate (item 6). Tighten the four (4) burner screws
(item 13) using a torque wrench. The screws must be secure,
but the torque must not exceed 20 inch-pounds.
4. Apply a ring of silicone adhesive on the cover plate (to secure
the refractory).
5. Slide the refractory (item 12) over the burner. Align the refrac-
tory and press in place.
– 120 –
-
GAS FIRED WATER BOILER
Figure 124
A
B Boiler interior, with
C Combustion chamber cover
D Disassembling to access the
E Heat exchanger interior
F Exploded heat exchanger
1 Inlet air silencer
2 Blower assembly
3 Gas valve
6.
7. Reinstall the igniter assembly (item 7).
8. Reinstall the cover plate assembly (items 2 and 6) and secure
9. Reconnect the igniter wire and the igniter ground wire.
10. Reinstall the blower/venturi/gas valve assembly.
11. Reinstall the air inlet silencer (item 1) by pressing onto the
12. Reconnect the flexible gas line to the gas valve using two
13. Reinstall the condensate trap and bracket on the boiler
— Boiler Manual
Legend for Figure 125, page 121
Boiler interior
components disconnected
to allow removal of
combustion chamber cover
plate
plate and components
removed from boiler
burner
view
handling the assembly, allow the adhesive to set
Before
enough that the refractory is firmly held in place.
a. The igniter gasket must be intact and in good condition.
Replace with a new gasket if necessary.
b. Insert the igniter into the cover plate opening, with the
gasket in position.
c. Reinstall the two (2) socket head Allen bolts finger tight.
d. Use a torque wrench to tighten the igniter bolts. DO NOT
exceed 20 inch-pounds torque.
the cover plate with 10-mm hex nuts (item 8).
You must gradually tighten the cover plate nuts us-
ing a torque wrench. The final torque MUST NOT
exceed 45 inch-pounds. Alternate tightening until
all nuts reach 45 inch-pounds.
a. Slide the blower/venturi/gas valve assembly up to the
cover plate, passing the two (2) threaded studs up through
the cover plate holes. Use the two (2) locking nuts to
secure the assembly.
b. Torque nuts to 20 in. lbs.
c. Reconnect the two (2) blower wiring harnesses and the
gas valve harness.
venturi.
wrenches. Snap the air silencer clip back into place.
condensate drain connection. (See Figure 74, page 65 for
reference.)
Perform a complete start-up procedure when put-
ting the boiler back into service. See page 90 and all
instructions for start-up and verification. Include a
soap suds leak test on all interior and exterior gas
piping after starting the boiler.
(continued)
4 Air silencer clip
5 Venturi assembly
6 Heat exchanger cover plate
7 Ignitor assembly
8 (4) Combustion chamber
cover plate retainer nuts
9 Burner
10 Burner gasket
11 Putty knife
12 Refractory
13 (4) Burner retainer screws
14 Boot for LP orifice
15 Cover plate gasket
Part number 550-142-204/0117