Unitary Products Group
7
278177-BTG-A-0407
APPLYING FILTER PRESSURE DROP TO
DETERMINE SYSTEM AIRFLOW
To determine the approximate airflow of the unit with a filter in
place, follow the steps below:
1.
Select the filter type.
2.
Determine the External System Static Pressure (ESP)
without the filter.
3.
Select a filter pressure drop from the table based upon
the number of return air openings or return air opening
size and add to the ESP from Step 3 to determine the
total system static.
4.
If total system static matches a ESP value in the airflow
table (i.e. 0.20, 0.60, etc,) the system airflow corre-
sponds to the intersection of the ESP column and Model/
Blower Speed row.
5.
If the total system static falls between ESP values in the
table (i.e. 0.58, 0.75, etc.), the static pressure may be
rounded to the nearest value in the table determining the
airflow using Step 5 or calculate the airflow by using the
following example.
Example:
For a 120,000 Btuh furnace operating on high
speed blower, it is found that total system static is 0.58" w.c.
To determine the system airflow, complete the following
steps:
1.
Obtain the airflow values at 0.50" & 0.60" ESP.
Airflow @ 0.50": 2152 CFM
Airflow @ 0.60": 2042 CFM
2.
Subtract the airflow @ 0.50" from the airflow @ 0.60" to
obtain airflow difference.
2042 - 2152 = -110 CFM
3.
Subtract the total system static from 0.50" and divide this
difference by the difference in ESP values in the table,
0.60" - 0.50", to obtain a percentage.
(0.58 - 0.50) / (0.60 - 0.50) = 0.8
4.
Multiply percentage by airflow difference to obtain airflow
reduction.
(0.8) x (-110) = -88
5.
Subract airflow reduction value to airflow @ 0.50" to
obtain actual airflow @ 0.58" ESP.
2152 - 88 = 2064
ACCESSORIES
PROPANE (LP) CONVERSION KIT -
1NP0347 - All units
This accessory conversion kit may be used to convert natural
gas (N) units for propane (LP) operation. Conversions must
be made by qualified distributor or dealer personnel.
CONCENTRIC VENT TERMINATION -
1CT0302 (2")
1CT0303 (3")
For use through rooftop, sidewall. Allows combustion air to
enter and exhaust to exit through single common hole. Elimi-
nates unslightly elbows for a cleaner installation.
SIDEWALL VENT TERMINATION KIT -
1HT0901 (3")
1HT0902 (2")
For use on sidewall, two-pipe installations only. Provide a
more attractive termination for locations where the terminal is
visable on the side of the home.
COMBUSTIBLE FLOOR BASE -
1CB0314 - 14 1/2” Cabinet
1CB0317 - 17 1/2” Cabinet
1CB0321 - 21” Cabinet
1CB0324 - 24” Cabinet
COIL TRANSITION KIT -
1TK0914 - 14” Furnace
1TK0917 - 17” Furnace
1TK0921 - 21” Furnace
1TK0924 - 24” Furnace
These kits are required in downflow application when using
G*F* series coils. These kits are not required with MC/FC
series coils, but please ensure that the coil and furnace are
secured and that there are noair leaks.
CONDENSATE NEUTRALIZER KIT -
1NK0301
Neutralizer cartidge has a 1/2" plastic tube fittings for installa-
tion in the drain line. Calcium carbonate refill media is also
avaiable from the Source 1 Parts (p/n 026-30228-000).
HIGH ALTITUDE PRESSURE SWITCHES -
For installation where the altitude is less than 8,000 feet it is
not required that the pressure switch be changed. For alti-
tudes above 8,000 feet see kits below. Conversion must be
made by qualified distributor or dealer personnel.
1PS0901 - 060, 100, 120 MBH
1PS0902 - 080/1200 MBH
1PS0903 - 080/1600 MBH
1PS0904 - 040 MBH
ROOM THERMOSTATS
- A wide selection of compatible
thermosets are available to provide optimum performance
and features for any installation.
1H/1C, manual change-over electronic non-programmable
thermostat.
1H/1C, auto/manual changeover, electronic programmable,
deluxe 7-day, thermostat.
1H/1C, auto/manual changeover, electronic programmable.
* For the most current accessory information, refer to the
price book or consult factory.
