Unit Start Up Procedure - Carrier 50YER036 Installation, Operation And Maintenance Instructions

W a t e r- t o - W a t e r ( 5 0 Y E R ) S e r i e s - P u r o n
R e v. : 1 J u l y, 2 0 1 0

Unit Start Up Procedure

� WARNING! �
When the disconnect switch is closed, high voltage is
present in some areas of the electrical panel. Exercise
caution when working with energized equipment.
1. Adjust all valves to their full open position. Turn on
the line power to all heat pump units.
2. Operate each unit in the cooling cycle.
3. Operate each heat pump in the heating
cycle immediately after checking cooling
cycle operation. A time delay will prevent the
compressor from re-starting for approximately five
(5) minutes.
4. Establish a permanent operating record by logging
the unit operating conditions at initial start-up for
each unit.
5. If a unit fails to operate, conduct the following
checks:
a. Check the voltage and current. They should
comply with the electrical specifications
described on the unit nameplate.
b. Look for wiring errors. Check for loose terminal
screws where wire connections have been
made on both the line and low-voltage terminal
boards.
c. Check the supply and return piping. They must
be properly connected to the inlet and outlet
connections on the unit.
d. If the checks described above fail to reveal
the problem and the unit still will not operate,
contact a trained service technician to ensure
proper diagnosis and repair of the equipment.
Note: Units have a five minute time delay in the
control circuit that can be eliminated on the CXM
PCB as shown in Figure 8. See controls description
for detailed features of the control.
� WARNING! �
Verify ALL water controls are open and allow water flow
prior to engaging the compressor. Freezing of the coax or
water lines can permanently damage the heat pump.
26
®
Water Temperature Change Through
Source Heat Exchanger
Water Flow, gpm [l/m]
For Closed Loop: Ground Source
or Closed Loop Systems at 3 gpm
per ton [3.9 l/m per kW]
For Open Loop: Ground Water
Systems at 1.5 gpm per ton
[2.0 l/m per kW]
Coax Water Pressure Drop 50YER 036-120
Model GPM
30°F
Source/Outdoor Coax
4.5 1.7
036
6.8 4.1
9.0 7.1
7.5 1.5
060
11.3 4.0
15.0 6.9
15.0 1.7
120
22.5 4.4
30.0 7.6
Load/Outdoor Coax
4.5
036
6.8
9.0
7.5
060
11.3
15.0
15.0
120
22.5
30.0
Must use antifreeze if operation falls in grey area
Operation not recommded
Multiply PSI x 2.31 to determine ft of hd
Rise, Cooling Drop, Heating
°F, [°C] °F, [°C]
9 - 12 4 - 8
[5 - 6.7] [2.2 - 4.4]
20 - 26 10 - 17
[11.1 - 14.4] [5.6 - 9.4]
Pressure Drop PSI
50°F 70°F 90°F
1.3 1.0 0.8
3.4 2.8 2.4
6.0 5.1 4.5
1.3 1.1 0.9
3.4 3.0 2.7
6.2 5.5 5.0
1.4 1.2 0.9
3.8 3.3 2.7
6.8 6.1 5.0
0.6 0.5 0.3
1.4 1.3 1.1
2.6 2.4 2.2
1.4 1.3 1.2
3.5 3.2 3.0
6.2 5.8 5.5
1.6 1.4 1.3
3.8 3.5 3.3
6.8 6.4 6.0