Daikin DPS012 - DPS 016-028 Gas Pipe Manifold Pressure Adjustment

DPS 016–028 Gas Pipe Manifold Pressure Adjustment
For Two Stage Furnace
1. Read gas pressure at the Inlet Pressure Tap of the
Honeywell VR8305Q Gas Safety Control Valve (Figure
50) and conrm pressure is at 7.0" wc for natural gas or
11.0" for propane. Adjust upstream pressure reducing
gas regulator as required to obtain 7.0" wc gas pressure
for natural gas or 11.0" for propane.
2. The gas pipe manifold pressure for high fire (stage
#2) should be set at 3.5" wc for natural gas or 10.0"
for propane. Adjust the High Pressure Adjustment
Honeywell VR8305Q Gas Safety Control Valve
(Figure 50) as required. Screwing the adjustment
clockwise will increase pressure; counter clockwise
will decrease pressure.
3. The gas pipe manifold pressure for low re (stage
#1) should be set at 0.88" wc for natural gas or 2.5"
for propane. Adjust the Low Pressure Adjustment
Honeywell VR8305Q Gas Safety Control Valve (Figure
50) as required. Screwing the adjustment clockwise
will increase pressure; counter clockwise will decrease
pressure.
For Modulating Furnace:
1. Read gas pressure at the Inlet Pressure Tap of the
Honeywell VR8305Q Gas Safety Control Valve (Figure
50) and conrm pressure is at 7.0" wc for natural gas or
10.0" for propane. Adjust upstream pressure reducing
gas regulator as required to obtain 7.0" wc natural gas
pressure or 10.0 for propane.
2. The gas pipe manifold pressure for high re should be set
at 3.5" wc for natural gas or 8.2" for propane. Adjust the
High Pressure Adjustment on the Honeywell VR8305Q
Gas Safety Control Valve (Figure 50) as required.
Screwing the adjustment clockwise will increase pressure;
counter clockwise will decrease pressure.
3. The gas pipe manifold pressure for low re (stage #1)
should be set at 0.26" wc for natural gas or 0.74" for
propane.
Adjust the Low Pressure Adjustment on the Honeywell
VR8305Q Gas Safety Control Valve (Figure 50) as
required until pressure at the Honeywell VR8305Q Gas
Safety Control Valve Outlet Pressure Tap reads 0.26"
wc for natural gas or 0.74" for propane. Screwing the
adjustment clockwise will increase pressure; counter
clockwise will decrease pressure.
Adjust the Maxitrol M520B Modulating Valve (Figure 51)
Low Flow Adjustment screw until the gas pipe manifold
pressure reads 0.26" w.c. for natural gas or 0.74" for
propane.
Figure 50: Honeywell VR8305Q Gas Safety Control Valve
Used for Both Staged and Modulating Furnaces
White Rogers is also used — functionally the same but different in
appearance.
Figure 51: Maxitrol M520B Modulating Valve
High Pressure Adjustment
Pressure Regulator Adjustment
(under cap screw)
Low Pressure Adjustment
ON–OFF Gas Control Knob
Outlet Pressure Tap
Inlet Pressure Tap
Low Flow Adjustment Tap
(right side)
Low Flow Adjustment Tap
(left side)
opTIonal gas heaT
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