SM/SV-Space Master Unit Coolers (E316008_B)
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8.2
OPERATION CHECKOUT
With the system operating, check the supply voltage. The voltage must be /- 10% of the voltage marked
on the unit nameplate and the phase to phase unbalance should be 2% or less.
LISTEN CAREFULLY to the unit to make sure there are no unusual sounds. Sounds such as a noisy motor, the
fan(s) scraping on the housing, or loose fasteners allowing parts to rattle need to be addressed immediately
before continued unit operation.
Check the room THERMOSTAT setting. Be sure it functions properly.
For DIRECT EXPANSION systems let the system balance out at the desired room temperature and check the
operation of the expansion valve by properly measuring the superheat at the sensing bulb. As much as thirty
minutes may be required for the new balance to take place after an adjustment is made.
For BRINE or GLYCOL COOLING systems keep the closest vent to the coil open while the fluid fills the coil to
allow trapped air to escape. Close the vent valve once fluid flows out of the valve and check for water hammer
in the coil.
With HOT GAS DEFROST systems allow the coil to frost, then manually advance the defrost timer to initiate a
defrost cycle. Observe the defrost cycle to see if all controls are functioning properly and that the coil is clear of
all frost before the system returns to refrigeration. Adjust the time clock pins if necessary. Reset the defrost
timer to the correct time of day. A defrost cycle is only needed when the frost build up is such that it impedes
the airflow through the coil. The defrost requirements will vary on each installation and may change depending
on the time of the year and other conditions.
With ELECTRIC DEFROST systems allow the coil to frost then manually advance the defrost timer to initiate a
defrost cycle. Observe the defrost cycle to see if all controls are functioning properly and that the coil is clear of
all frost before the system returns to refrigeration. Adjust the time clock pins if necessary. Reset the defrost
timer to the correct time of day. A defrost cycle is only needed when the frost build up is such that it impedes
the airflow through the coil. The defrost requirements will vary on each installation and may change depending
on the time of the year and other conditions.
9
PREVENTATIVE MAINTENANCE
A preventive maintenance schedule should be established as soon as the SM/SV Series unit is installed. The unit
should be inspected periodically for proper operation and build up of frost and debris.
WARNING: All power to the evaporator must be off before cleaning or performing maintenance.
9.1
DRAIN PAN
Inspect and clean the drain pan to insure free drainage of condensate. The drain pan should be cleaned regularly
with warm water and soap.
If the drain pan needs to be removed, support the long dimension of the pan from underneath with a minimum of
two 4x4s for one and two fan units, or two 6x6s for three and four fan units, so the outer sheet metal skin does
not buckle and become damaged.
Do not point load the center of the support beam.
For longer pans more
than one lifting device may be needed to keep the pan balanced when lifting. If the drain pan uses hot gas
defrost make sure the coil is completely pumped out and isolated with hand valves to prevent refrigerant from
escaping to the atmosphere. Remove electric wires if the unit has an electric defrost drain pan. Remove the drain
line so that it is out of the way of the pan when it is being lowered. Remove the drain pan attachment bolts from
the bottom of the evaporator unit and slowly lower the pan from the unit. Assemble pan in reverse order.
Replace hot gas interpiping gaskets before tightening flange bolts.
