Specifications
        21 
4. Start-up Procedures 
4.1. Pre Start-up 
A complete start-up is required to ensure all 
systems have been setup and adjusted to 
ensure optimum and reliable unit operation. 
The final adjustment and balancing must be 
done when all space and water 
temperatures are at design conditions. The 
use of auxiliary or portable air heaters may 
be required to heat the room. Read this 
section thoroughly before attempting to 
commission the Seresco dehumidifier. 
N
OTE: Do not use the unit as a construction 
site heater. Construction dirt will invade the 
unit and can significantly deteriorate unit 
performance and lifespan. 
1.  Ensure the unit installation conforms to 
all recommendations made by Seresco 
in this manual.
2. 
Check to ensure all packing materials 
and shipping brackets have been 
removed from the unit.
3. 
Leak test (with halogen leak detector) all 
factory and field piping. Shipping and 
handling may have caused refrigerant 
leaks inside the dehumidifier. 
4.  Check the nameplate for power 
requirements and confirm that it 
matches the available power supply. 
5.  Voltage must be within ±10% of the 
voltage printed on the nameplate. Verify 
that all field wiring matches the Seresco 
wiring schematics. Inspect and tighten 
all field and factory wiring. 
6.  Leave power on and allow 24 hours of 
crankcase heater operation before 
attempting the start-up. 
7.  Check the drain pan and the 
condensate piping. Test the drain and 
prime the P-trap by pouring water into 
the drain pan. 
8.  Verify that any space heating coil is 
installed in the supply air duct (after the 
evaporator coil) and not in the return 
duct. 
9.  PV or PH models have a pool water 
heater. Energize the circulating pump 
and establish water flow. Inspect the 
piping and repair any water leaks. 
Ensure the control wiring has been 
installed between the unit and auxiliary 
pool water heater. 
10.  Ensure the control wiring has been 
installed to the outdoor air-cooled 
condenser. 
11.  Ensure all peripheral controls and 
sensors are connected and wired 
correctly. 
12.  Verify that all service valves in the 
refrigeration lines are fully open. 
13.  Inspect the air filters and coils to assure 
they are clean. If necessary, clean the 
coils and install new air filters. 
14.  Verify that the unit has appropriate 
vibration isolators and that the unit is 
level. 
15.  Complete the Pre Start-up checklist 
section of the Warranty 
Registration/Start-up Form (copy 
provided with the unit and on page 34 of 
this manual). 
4.2. Start-up Procedure 
All appropriate fields and sections of the 
Warranty Registration and Start-up report 
should be completed. A proper start-up 
requires that the unit be run and monitored 
in all modes of operation at design 
conditions with the operating data recorded 
on the forms provided in the annex of this 
manual. Seresco reviews every report to 
ensure all aspects of the system are 
functioning within normal operating 
parameters. Carefully follow the process 
detailed in the start-up report. 
If the space is not at design conditions at 
the time of the start-up, a follow up visit 
for final adjust and balance is required. 
Mail or fax the completed start-up report 
back to Seresco to validate your unit’s 
warranty. Seresco will archive it for future 
reference. If you do not have a start-up 
report, call the Seresco for a new copy or 
download a PDFversion from 
www.seresco.net
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