Engineered air EngA G-TRAC2, Инструкция по установке, эксплуатации и обслуживанию

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A
G-TRAC2
IOM-25 9 of 42 Mar 99 R7
Dip switch Block B – Fuel Curves/Air Curves
The GTRAC-2 has built in air to fuel ratio curves. The combination of these curves provides 16 possible settings. The curves
are selected by turning dipswitches on or off. These dipswitches are located in a slot below the set-point knob on the front
of the control. Dipswitches 1 and 4, on block A and B, adjust the gas valve curve; dipswitches two and five adjust the
combustion air curve.
There is a label attached to the unit indicating the factory dipswitch settings.
The correct curves for a particular burner will vary based on the gas valve, air shutter, and combustion air blower and unit
size. If there are problems with condensate forming in the flue, the burner can be set up to reduce the amount of
condensate formed. This will require the burner to operate with extra combustion air
(higher O
2
) in the mid-to-low fire
range. Increasing the amount of combustion air distributes the water vapor, formed during combustion, over a larger
volume of flue gases. This dilutes the concentration and lowers the dew point temperature. Note however, that increasing
the amount of excess air too much will reduce the burner efficiency, slightly.
Following are curve guides for setting up air/fuel mixtures.

Dipswitches 1 and 4 set gas valve curves.

Dipswitches 2 and 5 set air damper curves.
GAS CURVES
Gas
Curve Dip switch 1 Dip switch 4 Characteristics
1 OFF OFF
Undersized valve or high efficiency application. Lower O
2
in
mid-range.
2 OFF ON Normal Setting
3 ON OFF
Oversized gas valve or condensate reduction. More O
2
in mid-
range.
4 ON ON Even more O
2
in low and mid-range. *
* On versions manufactured after May 12, 1998.
AIR CURVES
Air Curve Dipswitch 2 Dipswitch 5 Characteristics
1 OFF OFF Rich (Lower O
2
in mid-range).
2 ON OFF Normal Setting
3 OFF ON Lean (More O
2
in mid-range).
4 ON ON Lean “S” curve
Dipswitch Block “C” – Low Limit, PI, CTRAC, 0

10 VDC Control
This dip switch block is located:
G-TRAC 2.1 - near the top on the back of the board.
G-TRAC 2.2 – through the small slot at the very top of the panel front.
The controller must be turned over to access these switches. This dipswitch block provides low limit enable or disable, and
control choices of “
Normal PI ”, “ CTRAC PI ” or “ Direct 0-10 VDC Control” (such as from a BMS) .