Weil-McLain 550-141-951/1002 manual Install propane gas orifice, Perform Boiler Manual start-up

GAS-FIRED WATER BOILER — Propane Conversion Instructions

You must read and have the Ultra Boiler Manual with you to	Figure 1 Gas component locations
proceed with these instructions.

Install propane gas orifice

1.Turn off electrical power to boiler at external line switch or breaker.

2.Remove jacket front door by removing two knurled head screws at lower front.

3.Lift door away from boiler to remove.

4.Shut off gas to boiler by closing the manual gas valve (Figure 1).

5.Remove propane orifice disc from conversion kit envelope. Read the stamping on the orifice.

The orifice stamping must agree with the boiler size (see front page). DO NOT proceed with installation if orifice is incorrect. Installing the wrong orifice could result in severe personal injury, death or substantial property damage.

6.Disconnect the gas line union (Figure 1).

7.Remove (3) star-drive screws securing gas valve to venturi (Figure 2).

8.Place orifice in the black rubber grommet in the gas valve outlet port (Figure 2).

9.Reposition gas valve against venturi and replace (3) screws securing valve to venturi.

10.Reconnect gas line union.

11.DO NOT ADJUST gas valve pressure. See WARNING, bottom right.

12. Perform leak test and gas pressure checks given on page 19 of Boiler Figure 2 manual. Verify gas pressure at gas valve inlet pressure tap is in the range

given on the front page of this document and in Boiler Manual.

Perform Boiler Manual start-up

Follow all instructions in Boiler Manual Section 7, pages 24 through 30, to start-up the boiler after converting for propane. Because the boiler has been changed, you must verify correct operation, including checking combustion with test instruments both at high fire and low fire as described in the Boiler Manual. Failure to comply could result in severe personal injury, death or substantial property damage.

Replace boiler jacket front door

Replace boiler jacket front door after servicing. The boiler front door must be securely fastened to the boiler to prevent boiler from drawing air from inside the boiler room. This is particularly important if the boiler is located in the same room as other appliances. Failure to keep the door securely fastened could result in severe personal injury or death.

Apply conversion label

1.After installation is complete, attach the propane conversion label (in instruction manual envelope) next to the boiler rating plate.

Installing propane orifice

DO NOT adjust or attempt to measure gas valve outlet pressure. The gas valve is factory-set for the correct outlet pressure. This setting is suitable for natural gas and propane, requiring no field adjustment. Attempting to alter or measure the gas valve outlet pressure could result in damage to the valve, causing potential severe personal injury, death or substantial property damage.

Part number 550-141-951/1002