Section 7: Commissioning The Corayvac System; Setting The Corayvac End Burner Vacuum - Roberts Gorden UltraVac NEMA 4 Installation Manual

SECTION 7: COMMISSIONING THE CORAYVAC
NOTE: The ROBERTS GORDON
software must be installed on the PC, the communi-
cation connection must be made to the controller and
all wiring of the ROBERTS GORDON
control boards, relay boards, burners, pumps and
VFD must be completed before starting the commis-
sioning procedure.
7.1 Setting The CORAYVAC
It is important to understand that the frequency that
the VFD runs the motor at, determines the speed of
the impeller in the pump. Variation of the impeller
speed will increase or decrease vacuum in the sys-
tem. The following procedure will help you set mini-
mum and maximum VFD frequency settings to
achieve proper vacuum in the system.
Step 7.1.1 At the controller, turn on the 24 V power
switch on the relay board. At the PC, "connect" to the
controller (see the ROBERTS GORDON
VAC™ Software Installation and Operation Manual,
P/N 10081600NA for details) and then open the
manual override screen(Alt + M). On the screen,
click the "ON" button for the vacuum pump. Wait 30
seconds then click the ON button for zones 1-3.
Step 7.1.2 The pump should be running and the burn-
ers should light within 60 seconds. At the VFD, verify
that the number displayed on the LCD screen is
"60.0" If it is lower than 60.0, hit the "up" arrow button
on the VFD until the number reads 60.0 Let the burn-
ers fire for approximately 20-30 minutes to warm up
the system. Using a manometer, check the end vent
vacuum in each zone (each branch of burners). See
Page 30, Figure 20.
If the lowest end vent vacuum reading is above 3.0"
wc, reduce the vacuum pump speed. Generally, the
lowest end vent vacuum reading is on the longest
branch of the system. Use the down arrow button on
the VFD to reduce the frequency of the output signal
to the pump, thus reducing the pump speed and low-
ering the end vent vacuum reading. Continue to
reduce the frequency until the end vent vacuum read-
ing is between 2.5" - 3.0" wc. Make note of this fre-
quency setting below. The frequency is found on the
VFD's LCD screen.
2.5" wc - 3.0" wc VFD Frequency Setting
Record Frequency Setting Here:
To avoid damage to the pump motor, do not adjust
the frequency above 60.0 Hz. Verify that the end vent
vacuum readings in the remaining branches are
®
® ULTRAVAC™
® ULTRAVAC™
® End Burner Vacuum
® ULTRA-
SECTION 7: C
SYSTEM
proper. If necessary, adjust the proper damper cou-
pling to achieve an end vent vacuum of 2.5" - 3.0" wc
See Page 30, Figure 20. Damper couplings should
be found near the end of the radiant portion of the
pipe in each branch or where a branch connects to
other branches at a cross or tee. See Page 31, Fig-
ure 21.
T CORAYVAC ® S
OMMISSIONING HE YSTEM
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