Dunkirk Q90-100 Series IV - Manual

HIGH ALTITUDE
MANIFOLD PRESSURE ADJUSTMENT
1. Turn off manual gas valve.
2. Remove manifold pressure tap plug marked “Outlet
Pressure Tap” from gas valve using 3/16” Allen wrench.
Install ⅛” NPT x ¼” barbed fi tting. See Figure #1
3. Connect manometer or gauge to gas valve pressure
tap barbed fi tting just installed in step 1. Manometer
should be capable of reading 1 to 15 inches of water
column. See Figure #2.
4.
Turn electrical power and gas supply on. Set
thermostat high enough to start boiler.
5. Start boiler.
6. Note gas manifold pressure on manometer or gauge.
Manometer or gauge reading should be 2½ inches
water column at start up.
7. To adjust manifold pressure, remove “Pressure
Regulator Adjustment Cap” located on gas valve
to gain access to regulator adjustment screw. Turn
adjustment screw clockwise to increase pressure and
counterclockwise to decrease pressure. See Figure
#1.
NOTICE
When doing this procedure, place pressure regulator
cap back in place to obtain correct reading. Not
putting cap in place gives false reading of manifold
pressure.
8. Adjust manifold pressure to indicated value using
known gas Btu value and known altitude of installation.
See Tables #1 and #2 on following pages.
P/N 240009672, Rev. D [06/2013]
Please read these instructions carefully before starting the adjustment or conversion process. These
changes must be performed by a qualifi ed service agency.
OFF
ON
INLET OUTLET
PRESSURE REGULATOR
ADJUSTMENT (UNDER CAP SCREW)
INLET
PRESSURE
TAP
VR8205
WIRING TERMINALS (2)
OUTLET
PRESSURE
TAP
SUPPLEMENTAL INSTRUCTIONS
DANGER
Before servicing, turn off electrical power to boiler
at service switch. Close manual gas valve to turn
gas supply OFF to boiler. Failure to comply will result
in death or serious injury.
!
9. Once correct pressure reading is obtained and remains
steady, shut off boiler at thermostat, shut off manual
gas valve, and electrical supply. Remove manometer or
gauge, ⅛” barbed fi tting and replace pressure tap plug.
10.
Restore electrical and gas supply, restart boiler and
check for gas leaks using soapy water or a commercial
leak detector.
11.
Fill out data on adjustment/conversion label and attach
to inside left panel of boiler.
Operate boiler through at least 6 ignition cycles to check for
proper operation of boiler before leaving job site.
Figure 1 - Gas Valve Detail
EFFECTIVE DATE SEPTEMBER 1, 2012