AERCO Electronic Control Valve - Manual (Page 29)

VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
8-5
CM34. Holding the Lower Shaft (16), carefully replace the entire Shaft/Seat/Piston assembly into the Valve
Body (1) and Seat Cage (2).
CM35. Thoroughly clean the gasket surfaces of the Valve Body (1) and Valve Top (21) of all dirt and
scale. If necessary, use a wire brush, emery or both.
CM36. See Figure 8-1 or 8-2. Reassemble these parts in the following order:
• NEW Valve Top Gasket (13)
• Valve Top (21)
• Cap Screws or Hex Hd. Bolts (14) – Valve sizes 2-1/2” to 4” use 1/2”-13 Cap Screws. Valve
sizes 1” to 2” use 3/8”-16 Hex Hd. Bolts. Tighten using an alternating pattern to provide a
uniform seal and prevent Valve leakage.
• NEW Packing Assembly (20)
• Packing Nut (18)
• Hex Nuts (17)
• Indicator Plate (See Figure 8-1 or 8-2)
CM37. Replace the Actuator (27), Linkage (26) and Gasket (29) onto the Valve Top (21) and secure with
Cap Screws (19).
CM38. Position the Hex Nuts (17) at the original location noted during the removal process.
CM39. Install the Indicator Plate on the Valve Shaft (16) with the curved end facing upward (Figure 8-4).
CM40. Attach the Valve Shaft (16) to the Linkage Adapter by rotating the Shaft counterclockwise (as
viewed from above). If the Valve Shaft cannot be turned by hand, use an open-end wrench to turn
the “double-nuts” on the Shaft until it engages the Linkage adapter threads. Insert the Shaft into
the Linkage Adapter until the Hex Nuts (17) are snug against the Indicator Plate.
CM41. Press down on the Valve Shaft (16) to compress the Pilot Spring (10) in the Valve Body.
CM42. With the Pilot Spring compressed, verify that the Indicator Plate is aligned with the “0” (zero)
marking on the Scale (28). If necessary, rotate the Valve Shaft until the Plate is aligned with the
“0” Scale marking.
CM43. If the Valve had been removed from the heating fluid line, replace it in. the line. Reconnect the
electrical connector plug to the Actuator.
CM44. Prior to placing the Valve back into service, perform the Control Valve Adjustment procedure in
Section 3.