Cashco 8310LP - Manual (Page 2)

2 IOM-8310HP/LP-BASIC
SECTION III
III. PRINCIPLE OF OPERATION
1. Movement occurs as pressure variations register on the
diaphragm. The registering pressure is the outlet P
2
,
or downstream pressure. The range spring opposes
di a phragm movement. As outlet pressure drops, the
range spring pushes the di a phragm down, opening
the ports; as outlet pres sure increases, the di a phragm
push es up and the port opening closes.
2. A complete diaphragm failure will cause the reg u la tor
to fail open.
IV. START-UP
1. Start with the block valves closed. A bypass valve may
be used to maintain outlet pressure in the down stream
system without chang ing the fol low ing steps.
2. Relax the range spring by turning the adjusting screw
counter clockwise (CCW) (viewed from above) a min-
i mum of three (3) full revolutions. This re duc es the
outlet (downstream) pres sure set point.
3. If it is a “hot” piping system, and equipped with a by-
pass valve, slowly open the bypass valve to preheat
the system piping and to allow slow ex pan sion of the
piping. Ensure proper steam trap operation, if installed.
Close ly monitor outlet (down stream) pressure via gauge
to ensure not over-pres sur iz ing. NOTE: If no bypass
valve is in stalled, extra caution should be used in start-
ing up a cold system; i.e. do everything slowly.
4. Crack open the outlet (downstream) block valve.
5. Slowly open the inlet (upstream) block valve ob serv ing
the outlet (downstream) pressure gauge. De ter mine if
the regulator is fl owing. If not, slowly rotate the regulator
adjusting screw clock wise (CW) (viewed from above)
until fl ow be gins.
6. Continue to slowly open the inlet (up stream) block valve
until fully open.
SECTION V
V. SHUTDOWN
1. On systems with a bypass valve, and where system
pressure is to be maintained as the reg u la tor is shut
down, slowly open the bypass valve while closing the inlet
(up stream) block valve. Fully close the inlet (up stream)
block valve. (When on bypass, the system pres sure
must be con stant ly observed and manually reg u lat ed.)
Close the outlet (downstream) block valve.
Do not walk away and leave a bypassed regulator
un at tend ed!
2. If the regulator and system are to both be shut down,
slowly close the inlet (upstream) block valve. Close the
outlet (down stream) valve only if regulator re mov al is
re quired.
7. Continue to slowly open the outlet (downstream) block
valve, especially when the downstream piping sys tem
isn’t pressurized. If the outlet (down stream) pressure
exceeds the de sired pres sure, close the block valve
and go to Step 2, then return to Step 4.
8. When fl ow is established steady enough that the outlet
(downstream) block valve is fully open, begin to slowly
close the bypass valve, if in stalled. NOTE: The needle
valve (39) is shipped in a full open position. If the system
is unstable due to pressure fl uctuations, slowly close
the needle valve (39) until the system becomes stable.
This needle valve (39) should never be in a fully closed
position.
9. Develop system fl ow to a level near its expected normal
rate, and reset the regulator setpoint by turning the
adjusting screw CW (viewed from above) to increase
outlet pressure, or CCW to reduce outlet pressure.
10. Reduce system fl ow to a minimum level and observe
setpoint. Outlet pressure will rise from the set point
of Step 9. The maximum rise in outlet pressure on
decreasing fl ow should not exceed the stated upper
limit of the range spring by greater than 10%; i.e. 10-40
psig (.69-2.8 Barg) range spring, at low fl ow the outlet
pressure should not exceed 44 psig (3 Barg). If it does,
consult factory.
SECTION IV
CAUTION C
DO NOT HYDROSTATIC TEST THRU AN IN STALLED
UNIT; ISOLATE REGULATOR FROM TEST. The upper
range spring pressure level listed on the name plate is
the rec om mend ed “up per operative limit” for the sens ing
di a phragm (see Section IV. Start-up, Number 7.) High er
pres sures could cause internal damage. In ad di tion, note
on the name plate that the Inlet and Outlet pres sure and
tem per a ture ratings are at dif fer ent levels.
10. Basic Regulator - (Refer to Figure 1): Regulator may
be rotated around the pipe axis 360°. Rec om mend ed
position is with spring chamber ver ti cal upwards. Orient
such that the spring chamber vent hole does not collect
rainwater or debris.
11. Regulators are not to be direct buried un der ground.
12. For insulated piping systems, recommendation is to not
insulate regulator.
CAUTION D