DriSteem Vapor-logic3, Инструкция по установке и эксплуатации

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STS ®
and LTS
® valve modulation
With a valve system, the modulation is very simple.
The demand signal simply determines how far the
valve is going to open. In other words, if the system
demand is 25%, the valve will be open 25%.
GTS
®
burner modulation
The burner assembly used on a GTS consists of a
variable speed blower, a constant air/gas ratio
modulating gas valve, and a burner. Depending upon
the burner size, the type of gas, and the venting
option, burner output can modulate from a minimum
of 25-90% of its rated capacity up to 100% of its
rated capacity. To accomplish this turndown, the
VAPOR-LOGIC
®
3
controller monitors the blower
tachometer feedback and uses it, in conjunction with
the system demand, to control the blower speed. As
the blower speed varies, the gas valve automatically
adjusts the amount of gas introduced into the burner
to maintain a constant air/gas ratio. This variable
combination of gas and air results in clean
combustion over the entire range of the burner
capacity.
Operation:
Valve and burner modulation
Modulation types: valves and burners.
Operation
When individual burner demand falls below its
minimum rating (25-90% depending on options),
burner operation changes from modulated to Time
Proportioned (TP). TP simply means that the burner
output is kept constant, but is cycled on and off. The
burner cycle time is two minutes, and the on time of
the burner is proportional to the system demand. The
breakpoint between burner modulation and burner
time proportioning depends upon system options.
To ignite the burner, the blower is run at a speed
optimized for ignition to provide the smoothest,
quietest, most reliable ignitions. If the tank is cold,
the unit will run at 100% capacity to preheat the tank.
Once the tank temperature rises above 88°C, the
burner will resume normal operation. In a two burner
system, one burner will always be running, while the
other burner may or may not be running depending on
system demand. Once both burners are off, they will
switch roles upon re-ignition to maintain even wear
on combustion system components.
VL3-IOM-0301-METRIC.pdf 44 11/19/2009 9:22:39 AM