Maintenance; Air System Adjustment; Duct Static Measurements - York AVV25B Installation Manual

SECTION XIV: MAINTENANCE
Filters must be cleaned or replaced when they become dirty. Inspect at
least once per month. The frequency of cleaning depends upon the
hours of operation and the local atmospheric conditions. Clean filters
keep unit efficiency high.
COIL CLEANING
CAUTION
!
Ensure adequate precautions are taken to protect electrical compo-
nents from liquid.
If the coil needs to be cleaned, it should be cleaned with water.
As an alternative to water, EVAP-Green by Nu-Calgon is the only pH
neutral coil cleaner approved to be used when it is properly diluted.
ENSURE THE CLEANED COILS ARE THOROUGHLY RINSED
AFTER USE OF EVAP-GREEN.
LUBRICATION
The bearings of the blower motor are permanently lubricated.
CONDENSATE DRAINS
During the cooling season check the condensate drain lines to be sure
that condensate is flowing from the primary drain but not from the
secondary drain. If condensate ever flows from the secondary drain the
unit should be promptly shut off and the condensate pan and drains
cleaned to insure a free flowing primary drain.
Johnson Controls Unitary Products
SECTION XV: AIR SYSTEM ADJUSTMENT
To check the Cubic Feet per Minute (CFM), measure the external duct
static using a manometer and static pressure tips. To prepare coil for
static pressure drop measurements run the fan only to assure a dry coil.
Drill 2 holes, one 12" away from the air handler in the supply air duct
and on 12" away from the air handler in the return air duct (before any
elbows in the duct work). Insert the pressure tips and read the pressure
drop from the manometer.
EXTERNAL DUCT STATIC
Measure the supply air static pressure. Record this positive number.
Measure the return air static pressure. Record this negative number.
Treat the negative number as a positive, and add the two numbers to-
gether to determine the total external system static pressure. If a filter
rack is installed on the return air end of the air handler or indoor coil sec-
tion, make sure to measure the return air duct static between the filter
and the indoor coil.
FIGURE 17: Duct Static Measurements
5292157-UIM-B-0317
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