Reznor YDSA Unit Installation Manual - Manual (Page 44)

Form I-Y, P/N 273646R6, Page 44
Gas Pressure Tap Location
Locate the 1/8” pressure tap on the manifold (See
FIGURE 24A, page 43). With the
manual valve turned OFF, connect a manometer to the 1/8” pressure tap in the mani-
fold. Both high-fire and low-fire pressure can be checked at the manifold pressure tap.
Open the manual valve.
Unit Test Mode Must be Enabled - Refer to Paragraph 10.3 to enable Test Mode
Follow the instructions to enter Test Mode and proceed to Test Mode Screen E.a.5.
Manifold Pressure Measurements
From the Test Mode Screen E.a.5:
•
Press the enter key until the cursor is flashing on the Heat Capacity: field.
Adjust the Heat Capacity value to 100% which will result in a signal of 10vdc
to the modulating gas valve.
•
Press the enter key until the cursor is flashing on the Stg 1: field.
Press the up arrow to set the Stg 1 value to ON.
Step 1 - High-Fire Manifold Pressure Reading
Using the manometer, measure the pressure on high fire. Check the pressure with
the chart on page 49. Normally adjustments to the factory settings should not
be necessary.
• If no adjustment is required, proceed to Step 5.
• If an adjustment is required, proceed to Step 2.
Step 2 - Single-Stage Valve Output Pressure
Set the value of Stg 1 to OFF. Locate the output pressure tap on the top of the single-
stage valve. Close the manual valve and connect a second manometer to the 1/8”
output pressure tap on the single-stage valve. Open the manual valve, set the value of
Stg 1 to ON, and measure the gas pressure.
If the output from the valve is not correct, remove the cap from the adjustment screw on
the single-stage valve. Adjust the output pressure setting by turning the regulator screw
IN (clockwise) to increase pressure. Turn the regulator screw OUT (counterclockwise)
to decrease pressure. Replace the cap.
CAUTION: DO NOT bottom out the gas valve regulator adjusting screw.
This can result in unregulated manifold pressure causing excess over
fire and heat exchanger failure.
Cycle the burner by turning the value of the Stg 1 field OFF and ON to actuate the
valve.
When the outlet pressure is correct, set the value of Stg 1 to OFF. Close the manual
valve and remove the manometer. Open the manual valve and proceed to Step 3.
Step 3 - Rechecking High-Fire Manifold Pressure
Set the value of Stg 1 to ON. Recheck the pressure at the manifold tap in the high fire
condition (Heat capacity field 100% 10vdc). Check the pressure with the chart on
page 41. Normally adjustments to the factory settings should not be necessary.
If no adjustment is required, proceed to Step 5.
If an adjustment is required, proceed to Step 4.
Step 4 - Modulating Valve High-Fire Pressure Adjustment
Follow the procedures in Step 4 to adjust the high fire output pressure of the modulating
valve.
Instructions for
Measuring Manifold
Pressure - Option AG73
(modulation with one
heat section)
NOTE: Two digital
manometers may be
required.
9.2.2 Checking Gas Pressure (cont’d)
9.2 Gas Heat Section (cont’d)
9.0 Optional Equipment including Heat Sections (cont’d)