Carrier AQUAZONE VQL, Инструкция по установке, запуску и обслуживанию

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Scroll Compressor Rotation —
It is important to be
certain compressor is rotating in the proper direction. To
determine whether or not compressor is rotating in the proper
direction:
1. Connect service gages to suction and discharge pressure
fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge
pressure should rise, as is normal on any start-up.
If the suction pressure does not drop and the discharge
pressure does not rise to normal levels:
1. Turn off power to the unit. Install disconnect tag.
2. Reverse any two of the unit power leads.
3. Reapply power to the unit and verify pressures are correct.
The suction and discharge pressure levels should now move
to their normal start-up levels.
When the compressor is rotating in the wrong direction, the
unit makes an elevated level of noise and does not provide
cooling.
After a few minutes of reverse operation, the scroll com-
pressor internal overload protection will open, thus activating
the unit lockout. This requires a manual reset. To reset, turn the
thermostat on and then off.
NOTE: There is a 5-minute time delay before the compressor
will start.
Unit Start-Up Cooling Mode
1. Adjust the unit thermostat to the warmest position.
Slowly reduce the thermostat position until the compres-
sor activates.
2. Check for cool air delivery at unit grille a few minutes
after the unit has begun to operate.
3. Verify that the compressor is on and that the water flow
rate is correct by measuring pressure drop through the
heat exchanger using P/T plugs. Check the elevation and
cleanliness of the condensate lines; any dripping could be
a sign of a blocked line. Be sure the condensate trap in-
cludes a water seal.
4. Check the temperature of both supply and discharge
water.
5. Air temperature drop across the coil should be checked
when compressor is operating. Air temperature drop
should be between 15 and 25 F.
Unit Start-Up Heating Mode
NOTE: Operate the unit in heating cycle after checking the
cooling cycle. Allow five minutes between tests for the pres-
sure or reversing valve to equalize.
1. Turn thermostat to lowest setting and set thermostat
switch to HEAT position.
2. Slowly turn the thermostat to a higher temperature until
the compressor activates.
3. Check for warm air delivery at the unit grille within a few
minutes after the unit has begun to operate.
4. Check the temperature of both supply and discharge
water.
5. Air temperature rise across the coil should be checked
when compressor is operating. Air temperature rise
should be between 20 and 30 F after 15 minutes at load.
6. Check for vibration, noise and water leaks.
Flow Regulation —
Flow regulation can be accom-
plished by two methods. Most water control valves have a flow
adjustment built into the valve. By measuring the pressure drop
through the unit heat exchanger, the flow rate can be deter-
mined. Adjust the water control valve until the flow of 1.5 to
2 gpm is achieved. Since the pressure constantly varies, two
pressure gages may be needed in some applications.
An alternative method is to install a flow control device.
These devices are typically an orifice of plastic material de-
signed to allow a specified flow rate that are mounted on the
outlet of the water control valve. Occasionally these valves
produce a velocity noise that can be reduced by applying some
back pressure. To accomplish this, slightly close the leaving
isolation valve of the well water setup.
Flushing —
Once the piping is complete, final purging and
loop charging is needed. A flush cart pump of at least 1.5 hp is
needed to achieve adequate flow velocity in the loop to purge
air and dirt particles from the loop. Flush the loop in both direc-
tions with a high volume of water at a high velocity. Follow the
steps below to properly flush the loop:
1. Verify power is off.
2. Fill loop with water from hose through flush cart before
using flush cart pump to ensure an even fill. Do not allow
the water level in the flush cart tank to drop below the
pump inlet line to prevent air from filling the line.
3. Maintain a fluid level in the tank above the return tee to
avoid air entering back into the fluid.
4. Shutting off the return valve that connects into the flush
cart reservoir will allow 50 psi surges to help purge air
pockets. This maintains the pump at 50 psi.
5. To purge, keep the pump at 50 psi until maximum pump-
ing pressure is reached.
6. Open the return valve to send a pressure surge through
the loop to purge any air pockets in the piping system.
7. A noticeable drop in fluid level will be seen in the flush
cart tank. This is the only indication of air in the loop.
NOTE: If air is purged from the system while using a 10 in.
PVC flush tank, only a 1 to 2 in. level drop will be noticed
since liquids are incompressible. If the level drops more than
this, flushing should continue since air is still being
compressed in the loop. If level is less than 1 to 2 in., reverse
the flow.
8. Repeat this procedure until all air is purged.
9. Restore power.
Antifreeze may be added before, during or after the flushing
process. However, depending on when it is added in the
process, it can be wasted. Refer to the Antifreeze section for
more detail.
Loop static pressure will fluctuate with the seasons. Pres-
sures will be higher in the winter months than during the warm-
er months. This fluctuation is normal and should be considered
when charging the system initially. Run the unit in either heat-
ing or cooling for several minutes to condition the loop to a
homogenous temperature.
When complete, perform a final flush and pressurize the
loop to a static pressure of 40 to 50 psi for winter months or 15
to 20 psi for summer months.
After pressurization, be sure to remove the plug from the
end of the loop pump motor(s) to allow trapped air to be
discharged and to ensure the motor housing has been flooded.
Be sure the loop flow center provides adequate flow through
the unit by checking pressure drop across the heat exchanger.
Antifreeze —
In areas where entering loop temperatures
drop below 40 F or where piping will be routed through areas
subject to freezing, antifreeze is needed.
To avoid possible injury or death due to electrical shock,
open the power supply disconnect switch and secure it in
an open position before flushing system.