Manual 2100-537
I
Page 25 of 54
START UP PROCEDURE FOR GROUND
LOOP SYSTEM
1. Be sure main power to the unit is OFF at disconnect.
2. Set thermostat system switch to OFF, fan switch to
AUTO.
3. Move main power disconnect to ON. Except as required
for safety while servicing, DO NOT OPEN THE UNIT
DISCONNECT SWITCH.
4. Check system airow for obstructions.
A. Move thermostat fan switch to ON. Blower runs.
B. Be sure all registers and grilles are open.
C. Move thermostat fan switch to AUTO. Blowing
should stop.
5. Flush, ll and pressurize the closed loop system per
IGSHPA guidelines.
6. Fully open the manual inlet and outlet valves. Start the
loop pump module circulator(s) and check for proper
operation. If circulator(s) are not operating, turn off
power and diagnose the problem.
7. Check uid ow using a direct reading ow meter or a
single water pressure gauge, measure the pressure drop
at the pressure/temperature plugs across the water coil.
Compare the measurement with ow versus pressure
drop table to determine the actual ow rate. If the ow
rate is too low, recheck the selection of the loop pump
module model for sufcient capacity. If the module
selection is correct, there is probably trapped air or a
restriction in the piping circuit.
8. Start the unit in cooling mode by moving the thermostat
switch to cool. Fan should be set for AUTO.
9. Check the system refrigerant pressures against the
cooling refrigerant pressure table in the installation
manual for rated water ow and entering water
temperatures. If the refrigerant pressures do not match,
check for airow problem then refrigeration system
problem.
10. Switch the unit to the heating mode by moving the
thermostat switch to heat. Fan should be set for AUTO.
11. Check the refrigerant system pressures against the
heating refrigerant pressure table in installation manual.
Once again, if they do not match, check for airow
problems and then refrigeration system problems.
NOTE: If a charge problem is determined (high or low):
A. Check for possible refrigerant leaks.
B. Recover all remaining refrigerant from unit and
repair leak.
C. Evacuate unit down to 29 inches of vacuum.
D. Recharge the unit with refrigerant by weight.
This is the only way to insure a proper charge.
