Williamson-Thermoflo PLB-112 LOW-BOY, Manual

Page: 18 / 26

PLB-112
Oil Furnaces
–
Furnace Manual
18
11/13
5. DIMENSIONS AND RATINGS (continued)
Table 12: Airflow Data, Models with ½ HP PSC Motors
0.2" (W.C.) 0.3" (W.C.) 0.4" (W.C.) 0.5" (W.C.) 0.6" (W.C.) 0.7" (W.C.)
HIGH
1680 1640 1600 1590 1540 1460
MED-HIGH
1210 1190 1180 1160 1130 1110
MED-LOW
1110 1070 1040 1010 970 930
LOW
960 940 920 890 860 830
BLOWER
SPEED
EXTERNAL STATIC PRESSURE WITH AIR FILTER
Table 13: Airflow Data, Models with ¾ HP ECM Motors
SW1- HEAT
DIP switch position
HEAT INPUT
(USGPH)
CFM with SW3-ADJ
DIP switch position A
CFM with SW3-ADJ
DIP switch position B
CFM with SW3-ADJ
DIP switch position C
A
(1=OFF, 2=OFF)
0.68 1160 1275 1045
B
(1=ON, 2=OFF)
0.80 1340 1475 1205
C
(1=OFF, 2=ON)*
0.68 1000 1100 900
D
(1=ON, 2=ON)*
0.80 1160 1275 1045
SW2- COOL
DIP switch position
A/C size
(TON)
CFM with SW3-ADJ
DIP switch position A
CFM with SW3-ADJ
DIP switch position B
CFM with SW3-ADJ
DIP switch position C
A
(1=OFF, 2=OFF)
4.0 1200 1380 1020
B
(1=ON, 2=OFF)
3.5 1050 1210 875
C
(1=OFF, 2=ON)
3.0 900 1035 765
D
(1=ON, 2=ON)
2.5 750 865 640
SW2- COOL
DIP switch position
A/C size
(TON)
CFM with SW3-ADJ
DIP switch position A
CFM with SW3-ADJ
DIP switch position B
CFM with SW3-ADJ
DIP switch position C
A
(1=OFF, 2=OFF)
4.0 1600 1750 1440
B
(1=ON, 2=OFF)
3.5 1400 1540 1260
C
(1=OFF, 2=ON)
3.0 1200 1320 1080
D
(1=ON, 2=ON)
2.5 1000 1100 900
SW4- DELAY
DIP switch position
HEAT INPUT
(USGPH)
PreRun On-Delay
CFM Level - Time
ShortRun On-Delay
CFM Level - Time
Off-Delay
CFM Level - Time
A
(1=OFF, 2=OFF)
0.68 13% - 45 sec. 19% - 60 sec 38% - 3 min.
B
(1=ON, 2=OFF)
0.80 13% - 45 sec. 19% - 30 sec 38% - 3 min.
C
(1=OFF, 2=ON)
All 13% - 45 sec. 100% - 0 sec 100% - 2 min.
D
(1=ON, 2=ON)
All 13% - 90 sec. 100% - 0 sec 100% - 2 min.
No adjustment
required
A/C size
PreRun On-Delay
CFM Level - Time
ShortRun On-Delay
CFM Level - Time
Off-Delay
CFM Level - Time
- All NO DELAY NO DELAY 100% - 90 sec
NOTE:
Disconnect main power to unit prior to changing DIP switch settings.
OIL HEATING MODE
24 VAC input (R) on W only
CONTINUOUS FAN
24 VAC input (R) on G only
In Cooling - Dehumidification mode, with no 24 VAC input to DH, the CFMs are reduced by 15%.
The CFMs shown are reduced by 20% if there is 24 VAC input to Y1 (first stage cooling mode)
PreRun and ShortRun are the periods of time when the the blower starts at very low CFM to minimize the distributon
of cool air in the system and then runs up to normal speed.
Off Delay is the time required to cool down the heat exchanger with low CFMs, to minimize cool draft in the air
distribution system.
COOLING OR HEAT PUMP HEATING MODE
24 VAC input (R) to G, Y/Y2 and O (for cooling)
DELAY PROFILE FOR OIL HEATING MODE
* Alternate adjustment in oil-fired heating mode for higher temperature rise
DELAY PROFILE FOR COOLING OR HEAT PUMP HEATING MODE