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FAQs

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Q)

Are your products compatible with the new alternative refrigerants?

A)

Yes, the R/S valves are compatible with most common HFC refrigerants and refrigerant oils.

Q)

Is there a problem with selecting valves according to the line size?

A)

Control valves should be selected according to load requirements and operating conditions. In most cases the control valve will be smaller than the line size. Service valves and hand valves are generally selected according to line size.

Q)

Why does my control valve hunt (chatter)?

A)

The frequent cause for hunting is the valve being oversized for the operating conditions. This often is the result of selecting a control valve by line size rather than operating conditions.

Q)

What is MOPD?

A)

Maximum Operating Pressure Difference. A valve will not open when its rated MOPD is exceeded.

Q)

Will refrigerant flow backwards through a solenoid valve or regulator?

A)

Yes. If the down stream pressure exceeds the upstream by the amount of the closing spring pressure, you will get reverse flow through the valve. Check valves installed down stream of the control valve will prevent this from happening.

Q)

Can control valves be installed in a vertical line?

A)

R/S recommends that all regulators and solenoids be installed perpendicular to a horizontal line (please consult us for exceptions).

Q)

Is it necessary to disassemble your hand valves before welding them in line?

A)

With larger valves and proper precautions disassembly in not required. However, R/S recommends disassembly to avoid seat damage.

Q)

What is MRP?

A)

It is the maximum rated pressure of the valve.

Q)

Do some R/S products qualify for Enhanced Capital Allowances (ECA's) under the UK Governments Energy Efficiency Best Practice Programme (EEBPP)?

A)

Yes. See FAQ- General topics and legislation.

See the section on the Climate Change Levy and Enhanced capital Allowance scheme.

Q)

Do you have any training courses for industrial valves?

A)

Yes. For further information please download details (13K Acrobat Reader file).

Q)

How are Parker industrial valves affected by PED97/23/EC?

A)

The Pressure Equipment Directive affects Parker pressure valves in different ways. Final implimentation of the Directive took place on 29th May 2002. Parker have used TUV Germany to verify their compliance. Key points concerning their compliance are as follows:

• Valves of 25-mm port and below are classified under the provisions of Sound Engineering Practice (SEP). Products covered by SEP do not (and should not) carry CE marks.

• Products classified in categories 1, 2, or 4 are required to carry CE marks. This would include products larger than 25mm and all safety devices.

• The materials used in manufacturing the R/S product meet the requirement of the PED. Materials being used include GGG40.3, ASTM 352 LCB, and stainless and carbon steel bar stock.

• All R/S solenoid coils are CE marked whether fitted to PED or SEP products, indicating that they meet EU electrical standards.

• Product descriptions for PED valves will indicate compliance, and these descriptions will appear on our delivery notes with a Declaration of Conformity.

• R/S conformity to PED is certified by TUV Germany (ID No. 0035).

Details of R/S and Flocon product classifications can be downloaded as an Acrobat Reader file (last update 29.5.02).