Westinghouse WGRGH**199 Series, Installation, Start-Up, Maintenance, Parts, Warranty

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WHL-060 REV. 1.6.16
4. Pour tankless water heater cleaning solution into the bucket. Ensure the cleaning solution is approved for potable water systems.
Place the drain hose (D1) and hose D2 to the pump inlet in the cleaning solution.
5. Open service valves (V3 and V4) on the hot water outlet and cold water inlet lines.
6. Turn on the circulation pump. Operate the pump and allow the cleaning solution to circulate through the water heater for at least 1
hour at a rate of 4 gallons per minute. This will remove any possible harmful scale deposits.
7. Rinse the cleaning solution from the water heater as follows:
a. Remove the free end of drain hose D1 from the bucket.
b. Close service valve V4 and open shutoff valve V2.
c.
Do not open shutoff valve V1.
d. Allow water to flow through the water heater for 5 minutes.
e. Close shutoff valve V2.
8. Disconnect all hoses.
9. Remove the cold water inlet filter from the water heater and clean out any residues.
10. Reinsert the filter and ensure the filter cap is securely tightened.
11. Connect electrical power to the water heater.
12. Open a hot water faucet. Run the water heater continuously for five minutes to ensure all cleaning solution is purged from the
system. Check for leaks and ensure the water heater is operating properly.
REPLACEMENT PARTS
NUMBER
DESCRIPTION PART NUMBER NUMBER DESCRIPTION PART NUMBER
B-1 M3 X 6 PH + MS 7855P-384 B-10 M4 X 12 TH + M/S 7855P-393
B-2 M4 X 8 PH + Self Tapping 7855P-385 B-11 M4 X 14 PH + Self Tapping 7855P-394
B-3 M4 X 8 TH + Self Tapping 7855P-386 B-12 M4 X 15 PW + M/S 7855P-395
B-4 M4 X 8 TH + MS 7855P-387 B-13 M4 X 20 TH + Self Tapping 7855P-396
B-5 M4 X 10 FH + M/S 7855P-388 B-14 M5 X 14 Flange Bolts M/S 7855P-397
B-6 M4 X 10 TH + Self Tapping 7855P-389 B-15 M5 X 10 TH+ M/S 7855P-453
B-7 M4 X 10 TH + M/S 7855P-390 B-16 M4 X 9 PH.PW + Self Tapping 7855P-296
B-8 M4 X 10 Flat Head 7855P-391 N-1 M4 Nut 7855P-398
B-9 M4 X 12 PH + M/S 7855P-392 N-2 M5 Nut 7855P-399
Table 33
– Replacement Bolts and Nuts
NUMBER DESCRIPTION PART NUMBER NUMBER DESCRIPTION PART NUMBER
O-1 Intake and Exhaust Adapter O-Ring 7855P-256 O-7 Gas Valve O-Ring 7855P-076
O-2
Combustion Analyzer Port Plug O-
Ring
7855P-334 O-8 P18 O-Ring 7855P-047
O-3 Exhaust Adapter O-Ring (75Ø) 7855P-254 O-9 P15 O-Ring 7855P-044
O-4
Exhaust Temperature Sensor O-
Ring
7855P-092 O-10 P20 O-Ring 7855P-282
O-5 Fan O-Ring 7855P-371 O-11 Flow Sensor Clip 7855P-254
O-6 Air-Gas Mixer Gasket 7855P-428
Table 34 - Replacement O-Rings and Clips