Aqua Comfort AC750 User manual

1
OWNER’S MANUAL
Vintage Signature Series models: AC750, AC1050, AC1100, AC1250, AC1500, AC1750
Manufacturing High Quality, High Efficiency
Heat Pump Pool Heaters
TABLE OF CONTENTS
SAFETY CONSIDERATIONS 2
INSPECTION 2
GENERAL INFORMATION 2
INSTALLATION 2
WATER FLOW & CONNECTIONS 2-3
ELECTRICAL CONNECTIONS 4
MODES OF OPERATION 5
WIRING DIAGRAMS 6
ELECTRONIC CONTROL PANEL 7
CHEMICAL USE 8
START-UP 9-1
MAINTENANCE 1
TROUBLESHOOTING CHECKLIST 11
CALLING FOR SERVICE 12
WARRANTY 13
WARRANTY REGISTRATION 14
Proudly Made in the USA
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888
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475
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ALL IN-GROUND
MODELS
INSTALLATION,
OPERATION,
MAINTENANCE
& SERVICE

2
SAFETY CONSIDERATIONS
• Qualified personnel should perform installation, maintenance and service.
• Make sure all field wiring conforms to the heater specifications and all national and local
codes.
• Disconnect all power sources before performing any maintenance or service to the heater.
INSPECTION
Immediately upon receipt, inspect cartons and their contents for damage due to transit.
Damage, if found, should be noted on delivery papers and a claim filed with the carrier. Also,
check unit data plate to make sure you have the proper model, before installing.
ENERAL INFORMATION
The information in this manual was prepared to assist in the proper installation, operation,
maintenance and service of your new heat pump pool heater. Please read the entire manual
and follow all instructions. Improper installation and use can result in damage to the heater,
unsatisfactory operation, and may void the warranty. Retain this manual for quick reference.
INSTALLATION
When selecting a location consider the following:
• Heater must be located outdoors.
• Minimum of 24” of clearance on access / service side of heater.
• Minimum of 18” of clearance on all three air intake sides of heater.
• Minimum of 48” of clearance for air discharge (top of unit).
• The heater should sit on a solid level surface sufficient above grade to prevent water from
entering it, and allowing condensate to drain from base.
• The length of water piping and electric should be kept to a minimum to avoid capacity loss
and decreased efficiency.
WATER FLOW & CONNECTIONS
Water connections are made at the rear of the heater. Both water in and out are labeled just
above the water connections. LEFT REAR = WATER OUT and RIGHT REAR = WATER IN.
2” unions are supplied and are made to accept 2” rigid PVC pipe. NOTE: unions can be used
for quick drainage of your heater and winterizing.
• Heater must be piped downstream from filter in the pool return line.
• Inline chlorinators must be piped downstream from heater. A check valve must be
installed between the heater and chlorinator to prevent drain back of the chlorine when
the pump is off. A chemical trap may also be piped at least six (6) inches above the

3
height of the chlorinator.
• When all the plumbing connections are complete, and ample drying time is allowed, run the
filter pump and check the entire system for water leaks.
• Make sure filter is clean and there are no obstructions in the filtering system.
• Proper water flow is essential to the performance of your heater. The minimum flow rate is 20 GPM.
TYPICAL WATER FLOW CONNECTIONS

4
ELECTRICAL CONNECTIONS
Field connections must comply with national and local codes. The work must be done by a qualified
electrician.
Heater must be permanently grounded and bonded.
Bonding will drastically reduce the chances of electrolysis, “Electrical Corrosion.”
Use copper conductors only.
Disconnect all power sources before performing any work on unit.
Standard Power Supply: 230/60/1
See unit data plate for specific ampacity.
Wiring Main Power Supply
1. Remove the screws from the plastic front panel, located on the control display side of the
unit.
2. Remove the screws from the front panel of the control box.
3. Route weather tight flexible conduit through the opening at the base of the unit. Connect
conduit to the bottom of the electrical control enclosure. A knockout is provided in the
bottom of the electrical control enclosure to accept either a ¾” or 1” fitting. Mounting conduit
directly to the electrical control enclosure will ensure a moisture tight seal, extending
the life of the heater.
4. Attach grounding conductor to the ground lug provided inside the electrical control enclosure.
5. Install L1 and L2 input conductors to the input lugs of the compressor contactor.
6. Connect bond wire (at least #8 solid copper wire) from bond lug on the right side of coil header
plate to the pool pump bonding terminal or other suitable location.

5
MODES OF OPERATION
To Change Between Pool and Spa Setpoints Manually:
This is the default factory setting (jumper on pins 1-2) and allows the user to change between the pool
and spa setpoints by using the mode button located on the front control panel. The use of an external
water pressure switch IS NOT required for this mode of operation.
To Change Between Pool and Spa Setpoints Automatically:
This change can be done automatically as the water flow is directed to either the pool or spa. The use
of an external water pressure switch in the spa piping IS necessary. A two-wire control circuit must be
connected from the water pressure switch to the terminals 9 and 10 on the terminal strip located in the
electrical control enclosure. The mode jumper must be on pins 2-3 for this mode of operation. See
figure 1 below for pin settings.
Remote Thermostats and Controllers:
If a remote thermostat or another control system is to be used to operate the heater, a normally open
dry contact can be made at terminals 11 and 12 on the terminal strip located in the electrical control
enclosure. Remove the red jumper from terminals 11 and 12 on the terminal strip and install the
remote control system. The mode jumper must be on pins 3-4 for this mode of operation. See figure 1
below for pin settings.
Mode
Configuration Pins
2
3
41
Electronic
Controller
Removable
Jumper
Terminal
Strip
1
2
3
4
5
6
7
8
9
10
11
12
Figure 1 – Terminal Strip & Mode Configuration Pins

6
WIRING DIAGRAMS
2 - Only on 080 models.
Table 1 - Jumper Configurations
Application Jumper Setting
Pool/Spa (1 Valve) 1&2
Pool/Spa (2 Valve) 2 & 3
Remote Automation 3&4
Pool Heater Series - Wiring Schematic 230/60/1
97P675-01 7/25/03
Factory low voltage wiring
Legend
Switch - High pressure
Switch - Low pressure
Relay coil
Field wire lug
Ground
Relay Contacts -
N.O., N.C.
olarized connector
Notes:
Factory line voltage wiring
Field low voltage wiring
Field line voltage wiring
Optional block
Quick connect terminal
Wire nut
Screw terminal -
field connection
CC -
H -
L -
Fan -
Compressor contactor
High pressure switch
Low pressure switch
Fan relay
L1
1 3 2
P
FS1 - Flow Switch 1
Capacitor
FS2 - Flow Switch 2
DC - Defrost Cycle
WT - Water Temperature
TThermistor
RM - Remote Automation
Microprocessor Control
TEST
PIN
CC
HP
LP
DC
WT
FS1
FS2
Field Installed Flow
Switch. See Table 1.
Remote Automation umper
1
2
3
IN 1 2 3
Field Installed home
automation control. See
Table 1.
See Table 1
Fan1
Interface Panel
9
10
11
12
TS
4
Green
5
6
7
8
TS
1
2
3
4
24
LP
LP
HP
HP
CC
CCG
F2
F1
C
IN 1
X3
X3
X2
X2
X1
X1
WAT
WAT
F
F
Comp esso
Unit
ower Supply
208-230/60/1
CC
T1
L1
T2
L2
G
C
R
S
RB
Fan Moto
2
4
T ansfo me
24V
Black/White
Yellow
Blue
230 V
Black
Com
PS
C
D
A
Red
208 V
Black
Blue
Brown
Blk/Wht
Violet
Black
Black
Blue
Blue
Red
Black
Blue
Brown
Blk/Wht
Violet
Black
Black
Blue
Blue
Red
5
1
Brown
Cap
Cap
Not Used
Yellow
Black
Green
Black
Brown
Orange
Blue
Red Black
Blue
Blue
Red
Red
Black
Black
Red
Black
Crankcase
Heater
Black
Black
Orange
Note 1
1 - Only on 105 models.
PTCR
Note 2
Notes:
1. Use only copper conductors.
2. Connect field wiring in grounded rain-tight conduit, per rating plate.
3. Connect bond wire to pool steel using #8 solid copper wire or larger.
4. All wiring must conform to national (N.E.C.) and local electrical codes.

7
ELECTRONIC CONTROL PANEL
+
I
POOL/SPA
STANDBY
HEAT
DEFROST
REMOTE
STANDBY
POOL
SPA
FAULT CODES
HP - High Pressure
LP - Low Pressure
F1 - Flow Sw itch 1
F2 - Flow Sw itch 2
FS - Remote Flow Switch
PO - W ter Sensor Open
HC - W ter Sensor Closed
dO - Defrost Sensor Open
dC - Defrost Sensor Closed
bO - Brown Out Protection
Figure 2 – User Interface Control Panel
Control Settings
Temperature Setpoint
• Temperature setpoint maximum for POOL mode is 95°F (35°C).
• Temperature setpoint maximum for SPA mode is 104°F (40°C).
To change the temperature setpoint, press the POOL/SPA/STANDBY button until you reach either
POOL or SPA mode, this will prompt the control to display the current temperature setpoint. Hold either
UP or DOWN button to scroll to your desired temperature setpoint. Once your new temperature setpoint
has been reached, release the UP or DOWN button. Your new setpoint will be displayed for fifteen
seconds then revert back to the actual pool or spa water temperature.
Note: When the mode jumper is in position 3-4 the setpoint must be changed on the remote control
system.
Selecting Pool or Spa Mode
Press the POOL/SPA/STANDBY button until you reach the desired mode. The LED indicator light will
verify the mode that has been selected. Note: When the mode jumper is in position 2-3 or 3-4 the mode
is determined by the external water pressure (flow) switch or remote controller.

8
CHEMICAL USE
Water quality must be checked regularly and maintained within recommended limits at all times.
Failure to maintain the proper water quality will greatly reduce the life of your heater.
• Never add chemicals directly into skimmer.
• Automatic chlorinators must be piped downstream from the heater. A check valve must be installed
between the chlorinator and heater to prevent raw chlorine from draining back into the heater. A chemical
trap may be piped at least six (6) inches above the chlorinator. See piping diagram B.
Always maintain the following water quality requirements:
PH LEVEL 7.4 to 7.8
CHLORINE CONCENTRATION 1 to PPM
TOTAL ALKALINITY 100 to 200 PPM
CALCIUM HARDNESS 100 to 300 PPM

9
START-UP
Before proceeding with this section make certain all plumbing connections are airtight and leak free.
Flow rates should not exceed 70 GPM maximum. Use of an external bypass is necessary at 70 GPM
and above. Minimum flow rate is 20 GPM.
• Turn filter pump time clock to the ON position and set filter pump hours. For initial heating, the pool
heater and filter pump may need to run continuously until your desired temperature is reached. After
initial heating is achieved, the heater will run only to maintain your desired temperature.
• Turn power supply to heater ON.
• The amber Standby LED will be activated.
• Select POOL or SPA and set your desired water temperature by scrolling either up or down.
• If your programmed water temperature is above the actual water temperature, the red HEAT
LED will light up indicating HEAT mode. The fan will start, and then the compressor will start.
NOTE: Each time the compressor turns off, it is protected by a 3-5 minute anti-short cycling delay.
Initial Heating
Initial heating may require you to run your heater and filter pump continuously for at least 24 hours,
or more, depending on the following factors:
• Temperature difference between actual water temperature and desired water temperature.
• Size of pool.
• Ambient air temperature, the cooler the air temperature the longer the heating time.
• Heat loss (evaporative, convective, radiative and conductive).
• A pool cover / solar blanket may reduce initial heating time by up to 50 percent.
Defrost Cycle
The heat pump pool heater has automatic defrost. When the outdoor temperature drops below 40 °F,
frost may start to form on the evaporator coil. Frost buildup will be heaviest on humid days when the
temperature is between 35-40°. During the defrost cycle, the Defrost LED will be illuminated to indicate
that the unit is defrosting. During this time the fan is running and the compressor is inactive.
Internal Protection Analyzers
The heater is equipped with internal devices to monitor and protect the integrity of the unit. Should an
abnormal condition occur, these devices will interrupt the operation of the unit and may display the
appropriate code on the control panel.
Reducing Heat Loss - Pool Cover / Solar Blanket
We highly recommend the use of a pool cover / solar blanket. Covering your pool is the single most cost
effective means of reducing heat costs from 50 to 70 percent. Heating a pool without a cover is like
heating a house without a roof. They also reduce the amount of maintenance costs. By reducing
evaporation, covers reduce the quantity of chemicals needed.

10
Because evaporation accounts for about 70 percent of pool heat loss, the beneficial effect of using a pool
cover / solar blanket can be dramatic.
Wind Speed Reduction
Reducing wind velocity at the water surface reduces convective and evaporative losses. Fences,
trees, hills, or tall hedges close to the pool perimeter are effective windbreaks. Locate these obstructions
to take maximum advantage of their effectiveness as windbreaks, without shading the pool surface
from the sun.
MAINTENANCE
WARNING: DISCONNECT ELECTRICAL POWER TO UNIT BEFORE STARTING ANY MAINTENANCE TO
PREVENT SERIOUS INJURY FROM SHOCK.
Protecting your Heater
• Keep your pool filter system clean and free of restrictions to ensure proper water flow.
• Check water chemistry regularly. Misuse of chemicals will cause permanent damage to your heater and
other pool equipment. Manufacturers can void warranties for damage as a result of poor water quality.
• Free airflow is essential. Keep the evaporator coil clean and free of weeds, leaves, glass clippings, dirt
and other debris that will decrease the airflow. Keep fences and shrubs away from air inlets (sides and
back of heater).
• Frequent rinsing of the evaporator with fresh water will remove build up from its surface. Always spray
the coil gently with a regular garden hose being careful not to bend aluminum fins.
• Regular cleaning of the cabinet will improve its appearance and extend the life of the finish.
Winterizing
When the heater is exposed to freezing temperatures, it is essential that all water within the unit be properly
drained. When water freezes it expands, damaging piping.
• Turn thermostat settings to OFF. Turn filter pump to OFF.
• Turn power to unit OFF (i.e. pull disconnect or turn circuit breaker OFF).
• Disconnect water inlet and outlet unions at the back of the unit, be careful not to lose rubber o-rings.
• Flush the heater piping out with fresh water to remove any residual chemicals.
• Use low-pressure air or vacuum to remove water that has accumulated inside the piping of the heater.

11
TROUBLESHOOTING CHECKLIST
1. Check to be sure that the electrical power is on. Reset the breakers or replace fuses if necessary.
2. Check to be sure the electronic control panel is set properly. The unit must be in either the Pool or Spa
mode and the desired temperature must be set above the actual pool or spa temperature for the heater to
run. If an error code is displayed, reference the table below to determine the cause.
3. Check to make sure the evaporator coil has enough clearance and that there are no restrictions to its
airflow.
4. Certain ambient air conditions may cause the heater to go into defrost mode. The Defrost mode will be
indicated by the Defrost LED.
NOTE: IT IS NORMAL FOR WATER TO DRIP FROM THE DRAINHOLES AT THE BASE OF THE HEATER.
THE UNIT PRODUCES CONDENSATE WHEN IT OPERATES.
The following table lists error codes as they would appear on the electronic control display. In the event
that an error does occur, check the possible causes list for the corresponding error to correct the problem.
Error Code Description Possible Causes
F1 Internal Flow Switch Open Little or no water flow
The pump is not running
The filter is dirty or clogged
Shortage of water to pump, air leak
Undersized pump
Valves not in correct position
Filter in backwash mode
Water pressure switch needs adjustment or is defective
FS Internal Flow Switch Open Remote
Mode Same as above
HP High Pressure Switch Open Low water flow to heater
Defective high-pressure switch
LP Low Pressure Switch Open Evaporator coil is dirty
Fan motor not running
Low refrigerant pressure
Defective low pressure switch
PO Water Thermistor Open Loose sensor wire
Defective water thermistor
HC Water Thermistor Closed Wire terminals touching
Defective water thermistor
dO Defrost Sensor Open Loose sensor wire
Defective defrost sensor
Dc Defrost Sensor Closed Wire terminals touching
Defective defrost sensor
bO Control Voltage Below 18VAC Low supply voltage to the unit

12
CALLING FOR SERVICE
• Please eliminate any water flow problems before calling for service.
• If you are unable to contact the installing agent, please go to www.aquacomfort.com or contact
AQUACOMFORT TECHNOLOGIES, LLC at 888-475-7443. A factory representative will assist you or your
serviceman over the phone.
SERVICE PERFORMED WITHIN THE WARRANTY PERIOD MUST BE APPROVED BY AQUA COMFORT TECHNOLOGIES,
LLC PRIOR TO SERVICE BEING PERFORMED AND ONLY BY AN AQUA COMFORT TECHNOLOGIES, LLC AUTHORIZED
TECHNICIAN. SEE WARRANTY FOR DETAILS.
Please have the following ready before calling:
IN-GROUND MODEL #:
SERIAL #:
DATE OF INSTALLATION:
NAME OF OWNER:
ADDRESS:
CONTACT #:
NATURE OF PROBLEM: