CleaverBrooks ProFire Q Series, Установка, эксплуатация и обслуживание

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Operation
3-4
750-437
Q Series Full Modulation
3.2.2 — Standby
The burner is in standby and ready to respond to a call for heat when
• All power supply switches are closed and power is present at the control panel as indicated by the burner's
illuminated white “power” light.
• The high limit control contacts are made. If the high limit has tripped (contacts open), it must be manually
reset.
• The burner's On/Off control switch is in the “ON” position.
• The AZL displays {OFF}.
3.2.3 — Startup
While burner is standby/{OFF}, and when the operating pressure/temperature falls below the operating control
set point the operating control contacts make/close. If all other devices in the limit string are made and the burner
switch is ON, the control sees a “call for heat” and then sequences through startup as follows (commentary in
italics)
{Ph22} = Fan motor on -
The burner energizes the fan
{Ph24} = Traveling to pre-purge position -
Airspeed ramps up to high-fire air delivery rate
{Ph30} = Pre-purge countdown timer (30 sec) -
Control confirms combustion air pressure is proven and then
pre-purges the heat exchanger to rid it of any possible accrued flammable vapors. The control displays {Ph30
XX.X} where “XX.X” is the countdown in seconds.
{Ph36} = Traveling to ignition position -
Airspeed and gas valve opening are positioned for ignition at the LMV's
P0 position.
{Ph38} = Pre-ignition Time - (ignition transformer ON) -
Direct spark transformer energizes the electrode
{Ph40} = 1st Safety Time - (safety shutoff valves ON) -
Gas delivered to the combustion zone.
{Ph42} = 1st Safety Time (ignition transformer OFF) -
Direct spark period terminates and flame presence
confirmed.
{Ph44} = Interval 1 - Flame stabilization
3.2.4 — Operation - Automatic Modulation
• The Control is in phase 60 and burner modulation is released to the load controller. The AZL presents {oP:
YY.Y} where “YY.Y” indicates the percent firing rate.
• The “YY.Y” firing rate is typically proportional to the difference between the load controller's set point and the
currently measured temperature or pressure value: large differences result in high firing rates with the firing rate
diminishing as the measured value approaches the setpoint value.
3.2.5 — Automatic Shutdown
• When the call for heat is satisfied, the operating control contacts open and the LMV3 control enters phase 62
where it commands the airspeed and fuel valve position to the P1 low-fire position.