Installation Guide

44
CIRCULATOR BLOWER SPEEDS
This furnace is equipped with an ECM circulator blower. The heat-
ing blower speed is shipped set at “B”, and the cooling blower
speed setting is “D”. These blower speeds should be adjusted by
the installer to match the installation requirements so as to pro-
vide the correct heating temperature rise and correct cooling CFM.
Use the dual 7-segment LED display adjacent to the DIP switches to
obtain the approximate airflow quantity. The airflow quantity is
displayed as a number on the display, rounded to the nearest 100
CFM. The display alternates airflow delivery indication and the op-
erating mode indication.
Example: The airflow being delivered is 1225 CFM. The display
indicates 12. If the airflow being delivered is 1275, the display
indicates 13.
1. Determine the tonnage of the cooling system installed with the
furnace. If the cooling capacity is in BTU/hr divide it by 12,000
to convert capacity to TONs.
Example: Cooling Capacity of 30,000 BTU/hr.
30,000/12,000 = 2.5 Tons
2. Determine the proper air flow for the cooling system. Most
cooling systems are designed to work with air flows between
350 and 450 CFM per ton. Most manufacturers recommend an
air flow of about 400 CFM per ton.
Example: 2.5 tons X 400 CFM per ton = 1000 CFM
The cooling system manufacturer’s instructions must be checked
for required air flow. Any electronic air cleaners or other devices
may require specific quantity of air, consult installation instruc-
tions of those devices for requirements.
3. Knowing the furnace model, locate the high stage cooling air
flow table. Look up the cooling air flow determined in step 2
and find the required cooling speed and adjustment setting.
Example: A *MVM970603BN furnace installed with a 2.5 ton
air conditioning system. The air flow needed is
1000 CFM. Looking at the cooling speed chart for
*MVM970603BN, find the air flow closest to 1000
CFM. A cooling airflow of 1000 CFM can be
attained by selecting the cooling speed “C” and
the adjustment to “normal”.
4. Continuous fan speed is selectable at 25%, 50%, 75% or 100% of the furnace’s maximum airflow capability.
Example: If the furnace’s maximum airflow capability is 2000 CFM, the continuous fan speed at 25% will be 0.25 x 2000 or
500 CFM.
5. Locate the blower speed selection DIP switches on the integrated control module. Select the desired “cooling” speed tap by
positioning switches 1 and 2 appropriately. Select the desired “adjust” tap by positioning switches 9 and 10 appropriately.
Refer to the DIP switch chart for switch positions and their corresponding taps. Verify CFM by noting the number displayed on
the dual 7-segment LED display.
6. The multi-speed circulator blower also offers several custom ON/OFF ramping profiles for cooling. These profiles may
be used to enhance cooling performance and increase comfort level. The ramping profiles are selected using DIP
switches 7 and 8. Refer to the bullet points below for a description of each ramping profile. Verify CFM by noting the
number displayed on the dual 7-segment LED display.
T O AVOID PERSONAL INJURY OR DEATH DUE TO ELECTRICAL SHOCK ,
TURN OFF POWER TO THE FURNACE BEFORE CHANGING SPEED TAPS .
WARNING
Model Tap
Low
Stage
Cool
High Stage
Cool
100%
Heat
*CFM
Low heat
CFM for
2 stage
A
398 599 953 667
B
557 817 1059 740
C 696 1007 1158 808
D 810 1212 1260 881
A
403 629 1202 855
B 540 806 1316 923
C
705 1023 1389 1033
D 819 1230 1396 1063
A
513 789 1228 867
B 660 967 1337 939
C 791 1182 1430 1016
D
913 1375 1516 1077
A 564 820 1818 1256
B
784 1133 1870 1292
C 982 1464 1910 1316
D
1259 1736 1957 1358
A 547 867 1891 1329
B 831 1160 1940 1362
C
1020 1467 1968 1390
D 1278 1910 2028 1440
A
433 656 938 687
B 541 790 950 751
C
686 972 986 814
D 806 1195 992 874
A 405 624 1057 758
B 549 808 1146 815
C 678 994 1256 882
D 784 1177 1349 946
A
556 837 1234 889
B
714 1022 1325 944
C 838 1206 1442 1019
D 991 1475 1528 1068
A
524 784 1759 1209
B 744 1078 1797 1249
C
927 1388 1840 1277
D 1185 1766 1881 1300
*100% CFM shown. CFM will vary proportionally with the gas valve BTU/H input.
*CVM970803BN
*CVM970804CN*
*CVM971005CN*
*MVM971005CN*
*MVM971205DN*
*CVM970603BN
*MVM970603BN*
*MVM970803BN*
*MVM970804CN*