Raypak 5042004 operating instructions Leak Test Procedure: Dual-SeatGas Valve, Post Start-UpCheck

Leak Test Procedure: Dual-Seat Gas Valve

Proper leak testing requires three pressure test points in the gas train.

Remove the access panel on the rear of the heater to access the gas valve for this test. Testpoint A is a blee- dle valve located upstream of the combination gas valve on the supply manifold.

Test point B is a bleedle valve located between the two automatic gas valve seats.

Test point C is a bleedle valve located downstream of both automatic gas valve seats and upstream of the manual valve. Refer to Fig. 49.

These tests are to be conducted with the electrical power to the heater turned OFF.

1.Manually close the downstream leak test valve.

2.Open the bleedle valve at test point A and connect a manometer to it. Verify that there is gas pressure and that it is within the proper range (NOTE: must not exceed 14.0 in. WC).

3.Open test point B and connect a rubber tube to it. Connect the other end of the tube to a manometer and look for a build-up of pressure. Increasing pressure indicates a leaking gas valve which must be replaced.

4.Next, close the upstream manual gas valve (field supplied) and remove the manometers from the bleedle valves in test point A and test point B. Connect a rubber tube from the test point A blee- dle valve to the test point B bleedle valve and open the upstream manual gas valve. Make sure that test point A & B bleedle valves have been opened so as to allow gas to flow. This will bring gas pressure to the second valve seat.

5.Open the bleedle valve at test point C and connect a second rubber tube to it. Connect the other end of the tube to a manometer and look for a build-up of pressure. Increasing pressure indicates a leak- ing gas valve which must be replaced.

6.Remove rubber tube and manometers. Close each test point bleedle valve as the tubes are removed.

7.After no leakage has been verified at all valve seats and test valves, open downstream leak test valve and restore electrical power to the heater.

		TO BURNER
GAS	A	B

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Fig. 49: Leak Test Procedure

Post Start-Up Check

Check off steps as completed:

1.Verify that the heater and heat distribution units or storage tank are filled with water.

2.Confirm that the automatic air vent (if used) was opened two full turns during the venting proce- dure.

3.Verify that air has been purged from the system.

4.Verify that air has been purged from the gas pip- ing, and that the piping has been checked for leaks.

5.Confirm that the proper start-up procedures were followed.

6.Inspect burner to verify flame.

7.Test safety controls: If heater is equipped with a low water cut-off or additional safety controls, test

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