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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 5 of 20
Figure 1. Benchmark 3.0 Low NOx (LN) Boiler
5.
WATERSIDE INSPECTION OF BENCHMARK 3.0 HEAT EXCHANGER
Benchmark 3.0LN units contain both a primary heat exchanger and a secondary heat
exchanger, as shown in Figure 2. Perform the waterside inspection as follows:
1. Ensure that the preliminary set-up and disassembly procedures in section 4 have been
performed to provide access to the unit‘s heat exchangers.
2. Allow the unit to cool prior before proceeding.
3. At the rear of the unit (Figure 3), slowly open the drain valve and drain the boiler water
from both heat exchangers.
4. Open the P&T relief valve, or loosen/remove the shell sensor to allow air to enter the
heat exchangers during draining.
5. After the heat exchangers have been drained, remove the 2-1/2 inch access port plugs
on the right side of the primary and secondary heat exchangers, as shown in Figure 2.
6. If waterside inspection is required by your local inspector, follow the inspector's
instructions. Upon satisfactory completion of the inspection, proceed to step 7.
7. Apply pipe compound to the threads of the access port plugs and replace them using a
pipe wrench.
8. Close the drain valve at the rear of the boiler.
9. Close the P&T relief valve or reinstall/tighten the shell sensor removed in step 4.
10. Open the water supply and return valves to the unit and refill the heat exchangers. This
completes the waterside inspection for the unit.