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Maintenance and Service (continued)
Electrical
The Refrigerating Specialties Division molded water resistant Class
"B" solenoid coil is designed for long life and powerful opening force.
The standard coil housing meets NEMA 3R and 4 requirements. This
sealed construction can withstand direct contact with moisture and
ice. The coil housing far exceeds the requirements of NEMA Standard
ICS, 1-110.57 salt spray test for rust resistance.
By definition, Class "B" coil construction will permit coil temperatures,
as measured by resistance method, as high as 130°C (266°F). Final
coil temperatures are a function of both fluid and ambient temperatures.
The higher fluid temperatures require lower ambient temperatures so
the maximum coil temperature is not exceeded. Conversely, low fluid
temperatures permit higher ambient temperatures.
The molded Class "B" coil is available from stock with most standard
voltages. However, coils are available for other voltages and
frequencies, as well as for direct current. Coils are also available as
transformer type with a 6 volt secondary winding for use with the
Refrigerating Specialties Division Pilot Light Assembly (see current
copy of Bulletin 60-10, "Pilot Light Assembly and Solenoid Transformer
Coil").
SYMPTOM
PROBABLE REASON
Regulator does not
Diaphragm or seat dirty, damaged or frozen.
shut off flow.
Diaphragm follower stuck or damged.
Piston jammed with excess dirt.
Throttling plug leaking due to excess
dirt or damage.
Diaphragm ruptured or badly deformed.
A4AB Modular Solenoid Pilot seat leaking.
A4AS Modular Solenoid Pilot seat leaking.
Diaphragm and seat eroded due to flash gas.
Modular Solenoid Pilot not closing.
Regulator does not
A4A (inlet) Pressure Regulator Diaphragm
open
ruptured or badly deformed.
Diaphragm follower stuck, damaged or frozen.
A4AS/A4AB Modular Solenoid
Pilot not opening.
Piston worn, too much clearance.
Regulator Operation
Diaphragm or seat dirty or damaged.
erratic.
Diaphragm follower has dirt on the outside
diameter or outside diameter is damaged.
Other system components, line controllers,
thermostats, etc., erratic.
Regulator too far oversized.
Pressure drop across
Inlet or outlet restricted.
regulator too high.
Regulator too small.
Large amount of flash gas in liquid line.
High pressure drop causes high rate of
expansion of gas at regulator outlet.
Regulator does not open all the way.
Refrigerating Specialties Division
SERVICE POINTERS (Check General Procedure)
The solenoid coil must be connected to electrical lines with volts and
Hertz same as stamped on coil. The supply circuits must be properly
sized to give adequate voltage at the coil leads even when other
electrical equipment is operating. The coil is designed to operate with
line voltage from 85% to 110% of rated coil voltage. Operating with a
line voltage above or below these limits may result in coil burnout.
Also, operating with line voltage below the limit will definitely result in
lowering the valve opening pressure differential. Power consumption
during normal operation will be 33 watts or less.
Inrush and running current is listed below:
Standard Coil
Vohs/Hertz
120/60 (Blue leads)
208/60 (Blue & Red leads)
240/60 (Red leads)
440/60 (Yellow & Red leads)
115/50 (Yellow & Blue leads)
230/50 (Yellow leads)
Other
On transformer coil the 6 volt leads are always black.
CORRECTION
Clean or replace. Clean strainer.
Clean or replace. Install follower carefully.
Remove and polish piston and bore with crocus cloth. Clean valve and
strainer.
Clean or replace. If used on liquid, check for
erosion due to excessive flash gas. Reduce flash gas by subcooling or by
reducing pressure drop across valve by providing restriction at valve outlet.
Replace. If Range "D" make sure has 2 diaphragms.
Check seat and needle. Replace as needed,
Check seat and needle. Replace as needed.
Replace. Reduce flash gas by subcooling or by reducing pressure drop
across regulator by providing restriction at valve outlet.
Check power at leads, make sure coil is de-energized.
Replace. It Range D make sure has 2
diaphragms.
Clean or replace. Install follower carefully.
Pressure drop across valve too high; over 21 bar (300 psig). Lower pressure
drop. Improper power supply. Correct. Replace solenoid coil.
Replace piston. Check for reason. If used on liquid, check for flash gas.
Clean or replace. Clean strainer.
Clean or replace.
Adjust, repair or replace.
Check load. Replace with smaller regulator or investigate use of reduced
capacity plug.
Check for restriction. Clean strainer.
Open manually to be sure valve is full open.
Replace with proper size regulator.
Reduce flash gas by subcooling. Reduce line restriction by increasing line
size, particularly at the regulator outlet. Replace with larger regulator.
Increase pipe size at the outlet of the
regulator.
Check piston for wear. Replace, it needed.
8
Inrush Running Fuse
Current Current
Size
(Amps) (Amps) (Amps)
1.1860
0.46
1
0.63
0.26
1
0.60
0.23
1
0.39
0.13
1
1.22
0.21
1
0.65
0.26
1
Contact Factory
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