Danfoss Pilot Operated Servo Valve ICS 25 - 65 (80)

Introduction

This guide provides detailed instructions for the installation, maintenance, and operation of the Danfoss Pilot Operated Servo Valve, ICS 25 - 65 (80).

Specifications

Refrigerants: Applicable to HCFC, HFC, R717 (Ammonia), and R744 (CO2). Flammable hydrocarbons are not recommended. The valve is recommended for use in closed circuits only. Contact Danfoss for further information.

Temperature Range: -60/+120 °C (-76/+248 °F)

Pressure Range: Designed for a maximum working pressure of 52 barg (754 psig).

Technical Data: The ICS can be used in suction, liquid, hot gas, and liquid/vapor lines. It regulates flow through modulation or ON/OFF function based on control impulses from connected pilot valves.

Regulating Range: Dependent on the chosen type and combination of pilot valves.

Opening Differential Pressure (p): A minimum opening differential pressure of 0.07 bar (1 psi) is required for the ICS main valve to begin opening, and 0.2 bar (3 psi) for it to be fully open.

Design (Fig. 4)

• 1. Body
• 2. Top cover
• 3. Function module
• 3a. Valve plate (Teflon) (available as spare part)
• 3b. Washer plate
• 4. Gasket
• 5. Bolts
• 6. Plug
• 7. Gasket
• 8. Manual operating spindle
• 9. Plug
• 10. Gasket

Installation

The valve must be installed with the spindle in a vertically upwards position (Fig. 1). Ensure the arrow on the valve is in the direction of flow and the top cover is upwards (Fig. 2). The top cover can be rotated 4 x 90° relative to the valve body.

If an external pilot valve is used, connect the pilot line to the upper side of the main line to prevent dirt and oil from entering the pilot line. Avoid using external control pressure for solenoid valve operation in liquid lines to prevent liquid hammer.

The valve is designed for high internal pressure. Piping systems should be designed to avoid liquid traps and thermal expansion pressure risks. Protect the valve from pressure transients like liquid hammer.

Welding (Fig. 3, 4, and 5)

Remove the top cover and function module before welding to prevent damage to O-rings and the Teflon valve plate. Lift out the function module using an M6 bolt screwed into the piston's threaded hole (Fig. 3). Clean any debris blocking the bolt hole.

Note: Remove all parts from the valve body before welding (Fig. 5). Internal surfaces and weld connections have an anti-corrosion treatment. Disassemble the valve just before welding/brazing to maintain this treatment. Protect disassembled function modules in polyethylene bags or with rust protection agent. Use only compatible materials and welding methods. Clean the valve internally after welding. Prevent welding debris and dirt from entering the valve body and function module. The valve body must be stress-free after installation. Do not mount valves where the outlet is open to atmosphere; it must always be connected to the system or properly capped.

Assembly

Remove welding debris and dirt from pipes and valve body before assembly. Check O-rings for damage. Apply refrigeration oil to ease insertion and protect O-rings. Check the top gasket for damage and replace if necessary.

Tightening (Fig. 6)

Tighten the top cover with a torque wrench to the values indicated in the table.

Colors and Identification

ICS valves are zinc-chromated from the factory. The zinc-chromatization does not cover welding connections. Valves can be painted for additional corrosion protection. Valve identification is made via the ID plate on the top cover. Protect the ID plate when painting.

Maintenance

Service

ICS valves are easy to dismantle. Do not open the valve under pressure. Relieve pressure by carefully opening the manual operating spindle. Small grooves along the thread will release refrigerant. Ensure correct local safety measures are taken.

Lift out the function module using an M6 bolt (Fig. 3). Clean any debris blocking the bolt hole.

When opening and removing the function module:

• Check O-rings for damage. A damaged O-ring may affect modulation.
• Check piston and cylinder for scratches and wear. Replace the function module if wear is excessive.
• Ensure cylinder and valve seat move freely with low friction.
• Replace the Teflon valve plate if damaged. Repair kits are available:

Repair Kits:

For mounting instructions, refer to DKRCI.PI.HSO.D.

Assembly

Remove dirt from the body before assembly. Ensure channels are not blocked by particles. Apply refrigeration oil to ease insertion and protect O-rings.

Tightening (Fig. 6)

Tighten the top cover with a torque wrench to the values in the table.

Note:

Always pay attention to the spindle during manual opener operation (Fig. 7):

1. Ensure the C-clip (C) is on the spindle (B) and intact.
2. When turning the manual stem clockwise to open, ensure the C-clip reaches the top nut of the packing gland. Do not over-torque; stop when the C-clip contacts the top nut.
3. To deactivate the manual opener, turn the spindle (B) counter-clockwise to the top point, then tighten further counter-clockwise to 8 Nm (5.9 lb/ft).
4. Remount the cap (A) and tighten clockwise to 8 Nm (5.9 lb/ft).

Use only original Danfoss parts, including O-rings and gaskets. Consult Danfoss if in doubt. Drawings are for illustration only.

UL Listing Information

The following text is applicable to UL-listed ICS 25-65 products: Applicable to common non-flammable refrigerants, including/excluding R717, and non-corrosive gases/liquids depending on sealing material compatibility. Design pressure must not be less than ANSI/ASHRAE 15 Section 9.2 for the refrigerant used.