– 10 –
Open
fi
rst main gas shut-off valve
slowly
. Reset high-
low gas pressure switches (if applicable). Check main
gas line for leaks using soap solution.
Heat is Enabled By The Following:
MDT And MRT Standard:
To
enable
the heat, rotate the
“Temperature
Setpoint”
knob
(MP-15)
clockwise to the desired
setpoint above the actual air temperature. The
allowable temperature range is 55
o
to 90
o
F.
MRT-PRO With Smart Room Sensor:
To
enable
the heat, press the
“Warmer”
or
“Cooler”
button on the face of the remote
MRT-Pro
room sensor
(TS-02)
to the desired room setpoint. Each push of the
button changes the temperature setpoint by 1
o
F. The
setpoint can be changed a maximum of + 10
o
F from
the default of 65
o
F.
Changing the heating setpoint
also changes the cooling setpoint.
MRT Expert or VDT Expert With A BACview (KP-01):
To enable the heat for MRT Expert scroll through
the “Setpoints” menu in the BACview and enter the
desired room Heating Occupied and Unoccupied
Setpoints. For VDT Expert enter the desired Heating
Discharge Air Setpoint.
Energy Savings Modes:
There are 3 Energy Savings Modes that could
disable the burner.
NOTE: A BACview or PC is required to change
Setpoints. For a more detailed control sequence,
see the Digital Control System Users Manual.
Setting Main Flame
CAUTION: You will have approximately three (3)
minutes before the unit shuts down on Freezestat
( L o w D i s c h a r g e Te m p e r a t u r e , i f y o u h a v e
disconnected plug wires TS-01 and TS-03). Referred
to in Section X.
NOTE: 3 OR 4 TRIALS MAY BE NEEDED TO
PURGE AIR FROM GAS LINE.
United Technologies Electronic Controls Spark
Ignitor (RE-02)
Watch microammeter carefully. Burner must hold in low
fi
re for approximately 10 seconds before modulating
up. The reading should be at least 0.5 microamps.
If the read-ing is too low, slowly turn the low-
fi
re
adjustment on the modulating valve in or out until
satisfactory readings are obtained. When adjusting
low
fi
re, there should be a continuous
fl
ame along the
entire burner length without any blowout spots.
Install manometer at test port on the last tee of the
burner manifold, or MR valve test port.
Slowly
open last manual gas shut-off valve.
Enable the fan and burner. Unit will run for 5 seconds
before valve opens and burner lights if all safeties and
limits are in normal operating mode.
NOTE: This is a direct spark ignition burner. Low
fi re may need to be adjusted fi rst in order to light
the burner.
Adjust high
fi
re pressure reading (from manometer) to
match Normal Manifold Pressure
fi
ring rate shown on
unit rating plate.
Refer to Valve Adjustment instructions in Section X
for setting high and low fi re gas pressure settings.
The high
fi
re setting must be made before adjusting
low
fi
re. Adjust the high
fi
re setting according to the
Maxitrol Valve Adjustment instructions in Section X.
The high
fi
re setting
must not
exceed the pressure
stated on the rating plate.
When adjusting low fi re, there should be a
continuous fl ame along the entire burner length
without any blowout spots.
Burner must hold in low
fi
re for approximately 10 seconds before modulating up.
Check
fl
ame signal with burner cycling through full
fi
ring
range.
Cycle burner several times to insure smooth light off.
Low
fi
re may need to be readjusted.
There should be a continuous spark for ten (10)
seconds with the last gas cock turned off and the
ignition control (RE-02) should lock out.
Check main gas lines for leaks.
Main
fl
ame is now set. Make sure burner modulates
and turn thermostat to the desired setting.
