Service manual

ROBERTS-GORDON SECTION 12: OPERATION pg 35
Section 12. Operation
Checking the Gas Line
1. Open main valve and verify that no gas is flowing
through the gas meter.
2. Purge the line if this was not done following pressure
testing with air.
3. Verify that the gas pressure is not above 14" w.c. (1/2
PSIG)
4. Close main gas valve.
Checking the Electrical System
1. Set all thermostats below room temperature.
2. Turn on power supply to the system controls.
3. Check to see that no part of the system (i.e. burners,
vacuum pump, outside air supply blower) is powered.
4. Individually check each zone by energizing the
thermostats separately. Each zone thermostat should
start the vacuum pump immediately. When the vacuum
pump reaches the nominal running RPM, the air
proving switch closes and activates the ignition
module. On VANTAGE
®
EV systems equipped with the
optional control panel, a pre-purge period of 45 to 60
seconds will precede burner ignition trial.
5. If more than one system is installed, be sure that no
part of one system is affected by the controls of a
different system.
6. Make a preliminary vacuum check at burners in
branches which have an adjustable damper coupling.
See Figure 33 for vacuum measuring instructions. This
check is to ensure that all dampers are open before
the system is fired. The vacuum measured in the
burner control housing should be approximately 1" to
1-1/2" w.c. differential or more.
Starting the System
Note: During the initial firing, the protective oil on the
tube may smoke for 30 to 60 minutes and
adequate ventilation should be provided.
The optional VANTAGE
®
EV control panel provides a pre-
purge, which delays energizing the burners for about one
minute after the vacuum pump starts, and post-purge,
which keeps the vacuum pump running for about one
minute after the last thermostat is satisfied.
1. Start with all thermostats below room temperature.
2. Open main gas valve.
3. Turn up thermostats one at a time, waiting to see that
all burners in a zone start. When the burner ignites, a
large blue flame will be observed through the viewer
window.
4. If any abnormal operation occurs, see the trouble-
shooting section of these instructions.
WARNING
Disconnect gas and electrical supplies before performing
service or maintenance.
Replace door before operating.
Failure to follow these instructions will result in death,
injury or property damage.