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

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
B-1 M3 X 6 PH + MS
B-2 M4 X 8 PH + Self Tapping
B-3 M4 X 8 TH + Self Tapping
B-4 M4 X 8 TH + MS
B-5 M4 X 10 FH + M/S
B-6 M4 X 10 TH + Self Tapping
B-7 M4 X 10 TH + M/S
B-8 M4 X 10 Flat Head
B-9 M4 X 12 PH + M/S
Table 33 – Replacement Bolts and Nuts
NUMBER DESCRIPTION
O-1 Intake and Exhaust Adapter O-Ring
Combustion Analyzer Port Plug O-
O-2
O-3 Exhaust Adapter O-Ring (75Ø)
Exhaust Temperature Sensor O-
O-4
O-5 Fan O-Ring
O-6 Air-Gas Mixer Gasket
Table 34 - Replacement O-Rings and Clips
PART NUMBER
7855P-384
7855P-385
7855P-386
7855P-387
7855P-388
7855P-389
7855P-390
7855P-391
7855P-392
PART NUMBER
7855P-256
7855P-334
Ring
7855P-254
7855P-092
Ring
7855P-371
7855P-428
NUMBER DESCRIPTION
B-10 M4 X 12 TH + M/S
B-11 M4 X 14 PH + Self Tapping
B-12 M4 X 15 PW + M/S
B-13 M4 X 20 TH + Self Tapping
B-14 M5 X 14 Flange Bolts M/S
B-15 M5 X 10 TH+ M/S
B-16 M4 X 9 PH.PW + Self Tapping
N-1 M4 Nut
N-2 M5 Nut
NUMBER DESCRIPTION
O-7 Gas Valve O-Ring
O-8 P18 O-Ring
O-9 P15 O-Ring
O-10 P20 O-Ring
O-11 Flow Sensor Clip
64
PART NUMBER
7855P-393
7855P-394
7855P-395
7855P-396
7855P-397
7855P-453
7855P-296
7855P-398
7855P-399
PART NUMBER
7855P-076
7855P-047
7855P-044
7855P-282
7855P-254
WHL-060 REV. 1.6.16