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Benchmark 3.0LN 24-Month Maintenance Kit 58015-04
Technical Instruction Document
TID-0135_0C
10
/12/2017
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, New York 10913
•
Phone: 800-526-0288
Page 11 of 20
6.1.4 Flame Detector Replacement
Flame detector (P/N
66034
) and gasket (P/N
81048
) are used on Benchmark 3.0 Low NOx
units. Complete the instructions below to replace these parts.
1. Refer to Figure 7 to locate the flame detector installation location.
2. Install the replacement flame detector and gasket in the location shown. Secure the
flame detector to the burner housing flange using the two screws removed in section
6.1.1, step 3.
3. Reconnect the flame detector lead wire.
FLAME
DETECTOR
IGNITER
BURNER
BURNER
HOUSING
Figure 7. Burner Assembly Igniter & Flame Detector Locations
6.1.5 Exhaust Manifold Inspection
The exhaust manifold of the Benchmark 3.0LN is installed on the top of the secondary heat
exchanger, at the rear of the unit, as shown below in Figure 8. Perform the following steps to
remove and inspect the manifold:
1. Remove the four (4) bolts securing the flue starter section collar to the top of the exhaust
manifold.
2. Disconnect the flue starter section from the exhaust manifold.
3. Disconnect the condensate trap drain hose from the 1-1/2" O.D. pipe on the bottom of
the exhaust manifold.
4. Using a 3/4" socket wrench, remove the five (5) bolts securing the exhaust manifold to
the heat exchanger (Figure 9). Also, remove the three (3) hex nuts from the manifold
PEM studs. Remove the complete exhaust manifold from the unit.
5. Remove the silicone rubber seal from the recess in the flange of the exhaust manifold.
Ensure that all seal residue is removed from the flanges of the exhaust manifold and
secondary heat exchanger.
6. From the opening at the top of the manifold, remove the condensate trap float (with
guide attached). Also, remove the orifice gasket located beneath the float.
FLAME DETECTOR GASKET
(
81048
)
FLAME DETECTOR
(
66034
)
IGNITOR
(
GP-122435-S
)