Dometic SEASTAR POWER ASSIST PA1200-2HP User manual

[REVISION P] Form No. 298403 | ©2022 Dometic
SEASTAR
POWER ASSIST (P/A)
Hydraulic Power Assist for SeaStar Steering Systems
Installation and User’s Manual — Book 17.2
EN

ii EN
All information, illustrations and specifications in this manual are based on
the latest information available at the time of publishing. The illustrations
used in this manual are intended as representative reference views only.
Moreover, because of our continuous product improvement policy, we
may modify information, illustrations and/or specifications to explain and/
or exemplify a product, service or maintenance improvement. We reserve
the right to make any change at any time without notice.
©2021 Dometic
All Rights Reserved. This document, subject matter and all information
herein is the sole, exclusive and confidential property of Dometic and shall
not be disclosed, copied, reproduced or used in whole or in part for any
purpose other than as specifically authorized in writing by Dometic.
is a registered trademark of the American Boat &
Yacht Council (http://www.abycinc.org)
SeaStar, SeaStar PRO, and BayStar are all trademarks of Dometic.
Loctite is a trademark of Henkel Corporation.
This book contains:
• the user’s manual for the SeaStar Power Assist (P/A) system.
• installation instructions for the SeaStar Power Assist (P/A) system.
• information for the following models: PA1200-2, PA1200-2HP, PA1206-2,
PA1225-2, PA1315-2.
About this Book

iii
EN
Table of Contents
Specifications .........................................................................iv
1 Important Safety Information .............................................. 1-1
1.1 Explanation of symbols .................................................... 1-1
1.2 Safe operation............................................................... 1-2
1.3 Safety considerations for installers .................................... 1-3
1.4 Safety labels.................................................................. 1-4
2 System Operation................................................................ 2-1
2.1 Pre-trip inspection......................................................... 2-3
2.2 Maintenance inspection................................................. 2-3
3 Installation........................................................................... 3-1
3.1 Before you start ............................................................. 3-1
3.1.1 Compatibility......................................................... 3-2
3.1.2 Tools required....................................................... 3-2
3.1.3 Installation overview .............................................. 3-3
3.2 Compensating line fitting installation ............................... 3-3
3.3 Pump installation........................................................... 3-5
3.3.1 Installing 90° fittings .............................................. 3-6
3.4 Plumbing the system – general requirements ..................... 3-7
3.5 SeaStar outboard front mount cylinders and I/O cylinder .... 3-8
3.5.1 Single cylinder diagram.......................................... 3-8
3.5.2 Dual cylinder installations....................................... 3-9
3.5.3 Triple cylinder installations .................................... 3-10
3.6 SeaStar outboard side mount and splashwell
mount cylinders ............................................................ 3-11
3.7 SeaStar inboard and sterndrive cylinders......................... 3-12
3.8 Autopilot connection detail........................................... 3-13
3.7 SeaStar inboard and sterndrive cylinders......................... 3-12
3.9 Electrical installation ..................................................... 3-14
4 Filling and Purging the System ............................................ 4-1
4.1 With Power Purge .......................................................... 4-1
4.2 Manual fill and purge..................................................... 4-2
4.2.1 Hydraulic fluid requirements ................................... 4-2
4.2.2 Fill and purge procedure ....................................... 4-2
4.3 System checks.............................................................. 4-7
4.3.1 Air removal check.................................................. 4-7
4.3.2 Fluid level check................................................... 4-7
4.3.3 System pressure test ............................................. 4-8
4.3.4 Interference checks............................................... 4-8
5 Troubleshooting Guide........................................................ 5-1
5.1 Warning lights .............................................................. 5-3
6 Accessories.......................................................................... 6-1
6.1 Fitting kits ..................................................................... 6-1
6.2 Dual ignition control kit part# HA1201............................... 6-1
6.3 Power harness fuse kits ................................................. 6-2
6.4 SeaStar Power Purge JR part# HA5445-2 ......................... 6-2

iv EN
7 Mounting Templates............................................................ 7-1
7.0.1 Floor mounting....................................................... 7-1
7.0.2 Wall mounting ....................................................... 7-3
8 Warranty...............................................................................8-1
8.1 2-Year limited warranty................................................... 8-1
8.2 Return goods procedure................................................ 8-2
8.3 Technical support ......................................................... 8-2
8.4 Authorised service centers & distributors ......................... 8-2
Specifications
Models All
Operating voltage 12/24V (automatically detected)
Working pressure 1000psi (6.9 MPa)
Maximum pressure 2000psi (13.8 MPa)
Relief pressure 2000psi (13.8 MPa)
Maximum pump flow rate 240 in3/min (3930 cc/min)
Average current draw ~3A
Maximum current draw, 12V (24V) 50A (25A)
Internal fuse rating 40A x2 (80A)
Recommended external use/breaker
rating, 12V (24V)
50A (25A)
Ignition wire maximum current draw 1A
Weight (w/o harness) 11.5lb (5.2kg)
Dimensions (w/o harness) H x W x D 11.1” x 6.2” x 6.5”
(28 cm x 15.7 cm x 16.5 cm)
Ignition harness length 25’ (7.6m)
Models PA1200-2
PA1200-2HP
PA1315-2
PA1206-2 PA1225-2
Power harness length 15’ (4.5m) 6’ (1.8m) 25’ (7.6m)
Power harness wire gauge 10AWG 10AWG 8AWG
3-3/4"
5"
8-3/16"
5/8"
2-1/2"
5"
5-1/4"
1-3/8"

1-1
EN
1 Important Safety
Information
Safe operation of SeaStar steering with Power Assist (P/A) depends on
proper installation and maintenance of the system, as well as the operator’s
safe judgment, boating knowledge, and expertise.
The installer and operator must read and understand the safety requirements
in this section before installing or using the steering system. If you have any
questions about safe installation or operation of this system, contact
Dometic Marine. Please don’t guess.
The symbols below are used throughout this publication to alert you to
potential hazards involved with the operation and installation of this product.
Observe these warnings and notices carefully. The safety alerts alone
cannot eliminate hazards; strict compliance with any special instructions
during installation, operation, and maintenance, along with common sense
operation, are important measures to prevent hazardous situations.
1.1 Explanation of symbols
DANGER!
Safety instruction: Indicates a hazardous situation that, if not avoided,
will result in death or serious injury.
WARNING!
Safety instruction: Indicates a hazardous situation that, if not avoided,
could result in death or serious injury.
CAUTION!
Safety instruction: Indicates a hazardous situation that, if not avoided,
could result in minor or moderate injury.
NOTICE!
Indicates a situation that, if not avoided, can result in property damage.
NOTE
Supplementary information for operating the product.

1-2 EN
General
• Read and understand this manual and any other documentation
provided with your steering system.
• Know and obey all applicable federal, state, and municipal laws and
regulations that govern boating in your area. Dometic recommends all
boat operators take a boating safety course.
• Never operate a boat while under the influence of drugs or alcohol.
Before every use
• Perform the pre-trip inspection described in section 2.1.
During use
• Wear a Coast Guard-approved personal flotation device (PFD).
• Attach the engine shut-off lanyard to your PFD.
• Do not allow anyone not familiar with the controls (steering, shift/
throttle) to operate the boat.
After use
• Rinse the steering cylinders thoroughly, using only fresh, clean water.
• Do not use acetone, or cleaners containing ammonia, acids, or any other
corrosive ingredients, on any hydraulic steering components.
• Some products formulated for cleaning fiberglass hulls are known to
aggressively corrode stainless steel shafts. If using a hull cleaner, avoid
overspray on the cylinders. Rinse off any overspray immediately with
fresh, clean water.
WARNING!
Do not operate the boat if any component is not in proper working order.
It may result in a loss of steering control, which could lead to a collision
and/or ejection from the boat, causing property damage, personal injury,
and/or death.
1.2 Safe operation
WARNING!
The safety information below is intended to inform you of hazards that
may be present when operating a boat equipped with electronic controls.
Read and understand this information.

1-3
EN
Before installation
• Read and understand this manual, and any other manuals supplied with
this system.
• Ensure you have all the required components on hand before you start.
• Do not use a wheel-mounted trim switch with coiled cord. The cord can
wrap around the steering wheel shaft and inhibit steering.
During installation
• Install components as instructed in this manual. Some component parts
and kits may contain additional installation instructions – refer also to
those instructions.
•
Do not substitute any component of the system without written authorization
from Dometic. Dometic parts are rigorously engineered and tested to
ensure system integrity. Substitution of components may compromise
safety, performance, and reliability.
• The steering cylinder must be compatible with, and rated for, the
engine(s) installed on the boat.
• If an instruction is unclear, contradictory, or you are otherwise unsure how
to proceed, do not guess. Contact Dometic Marine technical support.
After installation
• Perform the system inspection checks described in section 4.3.
• Correct any interference issues before handing the boat to the owner.
1.3 Safety considerations for installers
CAUTION!
We recommend that installation of the SeaStar Power Assist is performed
by a certified marine technician.
WARNING!
Failure to comply with these instructions may result in loss of steering
control, which could lead to a collision and/or ejection from the boat,
causing property damage, personal injury, and/or death.

1-4 EN
Figure 1-1. Safety labels.
WARNING!
If a decal is missing or becomes illegible, it must be replaced. Contact
Dometic technical support for a replacement copy.
1.4 Safety labels

H1 H2
C1 C2
H1 H2
C1 C2
HELM
PUMP
STEERING
LINES
COMPENSATING
LINE
POWER
ASSIST
UNIT
POWER
ASSIST
UNIT
HELM
PUMP
STEERING
LINES
COMPENSATING
LINE
SEASTAR OUTBOARD
CYLINDER
TILLER ARM
SEASTAR INBOARD
CYLINDER
2-1
EN
WARNING!
Always perform a pre-trip inspection of the steering system, as shown in
section 2.1, before use.
2 System Operation
How it works
The Dometic SeaStar Power Assist (P/A) is an electronically controlled gear
pump that is added into the hydraulic steering circuit between the helm
and steering cylinder. Fluid circulated by the helm pump enters the power
assist and is routed through the gear pump to the steering cylinder(s). The
helm becomes the control element, controlling speed and direction, while
the P/A is the working element, adding power to the steering fluid.
The helm pump controls the pump speed – the faster you turn the wheel,
the faster the gear pump will run. When you aren’t steering the P/A is
stopped, drawing only standby power.
Figure 2-1.
Using the power assist
The P/A is usually wired to turn on with engine ignition, in which case you
simply start your engine(s) and enjoy effortless steering from any helm on
your boat. The LED on the P/A will illuminate green when power is on.

2-2 EN
Some installers or builders will wire the P/A to turn on with an accessory
switch, or they may wire the accessory switch in series with the engine
ignition signal. In this case you will need to turn the P/A on with a switch.
This feature allows you to turn the power assist off and steer manually in the
event batteries are very low.
In multi-engine setups the P/A can be wired to turn on if any engine is
running, but some installers may elect not to wire it that way. Check with
the installer or builder.
NOTE
When steering loads are high it is possible to turn the helm faster than the
power assist can pump, in which case you will notice an increase in
steering effort. This won’t hurt the pump, but it won’t make the boat steer
any faster. Simply reduce your steering effort until you just feel an
increased resistance, at which point you’ll be steering at the maximum
rate of the P/A pump.
NOTE
Moderate pump noise when steering is normal. The location of the pump
and the material to which it is mounted will affect the volume.
Loss of power assist
If the P/A loses power the steering will revert to a manual hydraulic system.
You will be able to steer the boat normally, but with higher effort. In the
event you lose power assist, slow the boat to reduce steering load and
effort. Refer to the troubleshooting section for assistance.
Autopilot use
The P/A can be used with any hydraulic autopilot system. Simply engage
your autopilot as you normally would. There is no need to turn off the
power assist.

2-3
EN
2.1 Pre-trip inspection
2.2 Maintenance inspection
Perform the following inspection prior to every use:
1. Check the steering fluid level in the helm.
See section 4.3.2.
2. Verify immediate steering response when turning steering
wheel(s).
Turn the steering wheel slowly to port and to starboard through the full
range of motion and make sure the engines or rudders respond
immediately. Watch that the hoses move freely without snags or
hang-ups. Perform this check with and without the P/A turned on.
3. Inspect all steering hoses and fittings for wear, kinks, or leaks.
Check all steering hoses and fittings between the helm, power assist,
and cylinders for any signs of leakage, kinking, wear, or chafing. Check
that the fittings are tight.
4. Check for binding, loose, or worn steering components.
Perform a thorough system inspection as described in section 4.3:
• Every two months or 20 operating hours, whichever comes first.
• After any service that touches the steering system.
Ensure that any issues are corrected before using the boat.
WARNING!
Failure to comply with these instructions may result in loss of steering
control, leading to collision with obstacle(s), ejection from vessel resulting
in property damage and/or personal injury or death.
WARNING!
Do not operate boat if any component is not in proper working condition.
WARNING!
Do not operate boat if any component is not in proper working condition.

2-4 EN
Notes

3-1
EN
3 Installation
Installation of the SeaStar P/A should be performed by a qualified marine
technician. To ensure proper installation of the steering system:
• Familiarize yourself with the system and review the entire installation
procedure before you start installing components.
• Make sure you read and understand all the safety information in this
manual, and in any other manual included with the system.
• Check that you have all the components and tools you need.
If you need technical assistance, or wish to report an error in our
documentation, please contact Dometic technical support.
Email: [e-mail]
Phone: [phone]
3.1 Before you start
NOTE
Where a fastener torque is specified in this manual, the standard tolerance
is ±5% unless a range is given.
NOTE
Due to a small amount of internal hydraulic slip, a “master spoke” or
“centered” steering wheel cannot be maintained with a hydraulic steering
System. For best results, use an equal distance spoke steering wheel.
WARNING!
The SeaStar P/A unit has been designed and tested for use with marine
hydraulic steering only. Use in any other application may result in property
damage and/or personal injury or death.
CAUTION!
The SeaStar power assist is designed and validated for use with SeaStar
helms, steering cylinders, and hoses. Warranty may be void if products
from other manufacturers are used in the system.
WARNING!
Do not use a wheel-mounted trim switch with coiled cord. The cord can
wrap around the steering wheel shaft and inhibit steering.

3-2 EN
3.1.1 Compatibility
The SeaStar P/A and P/A PRO are designed for use in recreational marine
applications. See the matrix below for helm, cylinder, P/A, and hose
compatibility.
NOTE
The power assist can be used with helms of any displacement, but we
recommend 1.4, 1.7, and 2.0 helm pumps for optimal performance.
Table 3-1.
Helm compatibility Power Assist Model
PA12XX-2, PA1200-2HP PA1315-2 (PRO)
SeaStar ✓✕
SeaStar PRO ✕✓
Hose compatibility
SeaStar ✓✕
SeaStar PRO ✓ ✓
Nylon tube ✕
(may be used for compensating line only)
Cylinder compatibility
All SeaStar front mount
outboard cylinders
✓ ✓
All SeaStar inboard and
sterndrive cylinders (except
power steering cylinders)
✓ ✓
HC5380(-3), HC5370(-3)
or any other unbalanced
cylinder*
✓✕
* An unbalanced cylinder is one in which the sha exits one end of the barrel only.
3.1.2 Tools required
You will need the following tools to complete your installation.
• 1/2”, 5/8”, and 3/4” open end wrench.
• Electrical cut and crimp pliers.
• All other tools noted with your helm pump and steering cylinder
installation instructions.
WARNING!
Do not use with Baystar steering cylinders. The P/A can output enough
pressure to damage the Baystar support rods.

3-3
EN
3.1.3 Installation overview
STEP 1 – Install system components
Install the SeaStar helm(s) and steering cylinder(s) according to the
installation instructions provided with the components.
Install the compensating line fitting to the helm as shown in section 3.2.
Install the SeaStar power assist pump as shown in section 3.3.
Review the system plumbing requirements in section 3.4, then find
your configuration in sections 3.5 to 3.7 and make the required hose
connections.
If you have an autopilot pump, plumb it into the system as shown in
section 3.8.
Make the electrical connections as shown in section 3.9, but do not
turn on the power assist yet.
STEP 2 – Fill and purge the system
Fill and purge the hydraulic system as shown in section 4.
STEP 3 – System check
To complete the installation, perform the system checks outlined in
section 4.3 before using the boat.
NOTICE!
Do no run the P/A unit until the SeaStar steering system has been bled
free of air. Failure to do so may result in non-repairable damage to the
P/A unit.
NOTICE!
Do not attempt to install an NPT fitting into a -3 helm hose fitting port.
Doing so will lead to irreparable damage to the helm. Only use SeaStar
ORB hose fittings.
The helm, power assist, and autopilot (if equipped) each have a small fluid
reservoir. The compensating line (also called a reservoir line or return line)
connects these reservoirs together so that they act as a single, larger reservoir.
This connection can be made with hose or with SeaStar nylon tubing.
The helm has two reservoir ports, marked ‘R,’ on the rear cover. These
ports are shipped plugged from the factory, so you will need to install a
fitting. An ORB fitting is supplied with the power assist for installation on
helms with a ‘-3’ suffix in the part number. If you have an older helm with
NPT fittings you will need to order an NPT fitting kit, HF5540.
3.2 Compensating line fitting
installation

3-4 EN
ORB fittings:
Remove the plug from the bottom-most R port.
Thread the 45° fitting (supplied with the P/A) into the helm port until
the fitting washer (item 2) contacts the face of the helm port. Tighten
hand tight. Do not use a wrench.
Re-position the fitting to the desired orientation by turning it
counterclockwise to a maximum of one full turn.
While holding the fitting body securely with a wrench, torque the lock
nut (item 1) to 18 ft-lbs (24.4 Nm).
NPT fittings:
Remove the plug from the bottom-most R port, taking care to keep any
sealant residue out of the pump.
Clean sealant residue from the threads in the helm cover as thoroughly
as possible. Clean from inside out, and with threads facing down, to
avoid contaminating the helm.
Apply a liquid thread sealant, such as Loctite®565 PST, to the tapered
pipe thread of fitting, following the sealant manufacturer’s application
directions. Do not apply sealant to the straight-threaded portion of
the fitting.
Install the fitting in the pump body hand tight, then use a wrench to
tighten one turn. Tighten no more than one additional turn to align the
fitting to the desired orientation. Do not overtighten, as you may
damage the helm.
SECURE WITH WRENCH
HERE WHILE TIGHTENING
LOCKNUT (ITEM 1)
2
1
Figure 3-1.

3-5
EN
3.3 Pump installation
The SeaStar P/A can be wall-mounted to a bulkhead or transom, or floor-
mounted with the accessory mounting foot (included). Mounting
templates for wall and floor mounting are provided in section 7.
When determining where to mount the pump, consider the following:
• The P/A must be mounted in a dry location.
• The P/A must be mounted within 10° of vertical. Mounting in any other
orientation will result in a poor purge of air from the system, leading to
poor performance and possible safety hazard.
• The pump motor will get hot during heavy use. Do not mount the pump in
an area where fabrics or other flammable materials may contact the motor.
• The P/A will make noise comparable to an autopilot pump; consider this
if installing the pump in a center console, or in an area where you wish to
limit noise.
• The pump motor contains strong magnets that may affect a magnetic
compass. Ensure the power assist is at least 24” (60 cm) from a compass.
• The pump’s electronics may be affected by strong magnetic fields. Do
not mount the power assist within 12” (30 cm) of devices that generate
magnetic fields, such as electric motors (e.g. bilge pump).
• The straight fittings installed in the pump may limit where you can place
the pump while respecting the minimum bend radius of the hose. To
mount the pump closer to a bulkhead you can install 90° fittings in place
of the straight fittings. See section 3.3.1.
Figure 3-2.
WARNING!
Failure to correctly mount the P/A within 10° of vertical may lead to excessive
air in the steering system, leading to poor steering performance and/or
the potential loss of steering control, leading to a collision and/or ejection
from the boat leading to property damage, personal injury, and/or death.
R
H1
H2
10° 10° 10° 10°

3-6 EN
3.3.1 Installing 90° fittings
The minimum bend radius for SeaStar and SeaStar PRO hose is 3.5” (9 cm).
If you are installing the pump with the hose exit close to a bulkhead or other
obstruction that won’t allow a suitable bend radius, you can replace the
straight fittings at the pump output (labeled C1 and C2) with 90° fittings.
These are sold separately in kits of three fittings, part number HF5529.
To install:
Remove the straight fittings, taking care to keep any sealant residue out
of the pump.
Clean sealant residue from the threads in the pump body as thoroughly
as possible. Clean from inside out, and with threads facing down, to
avoid contaminating the pump.
Apply a liquid thread sealant, such as Loctite®565 PST, to the tapered
pipe thread of the 90° fittings, following the sealant manufacturer’s
application directions. Do not apply sealant to the straight-threaded
portion of the fitting.
Install the fitting in the pump body hand tight, then use a wrench to
tighten an additional two turns. Tighten no more than one additional
turn to align the fitting to the desired orientation. Do not overtighten,
as you may damage the pump body or fitting.
CAUTION!
Adjust fitting orientation immediately. Once the sealant begins to cure any
further adjustment will likely result in a leak, in which case you will need to
remove the fitting and re-apply sealant.
CAUTION!
Never use Teflon tape to seal any fittings in a SeaStar hydraulic steering
system. Use of Teflon tape will void the warranty.
Figure 3-3.

3-7
EN
WARNING!
Do not cut the hose or attempt to install reusable fittings. Failure of the
hose or fittings may lead to loss of steering control resulting in a collision
and/or ejection from the boat leading to property damage, personal
injury, and/or death.
WARNING!
Failure to comply with these plumbing requirements may lead to loss of
steering control resulting in a collision and/or ejection from the boat
leading to property damage, personal injury, and/or death.
CAUTION!
Contamination is the most common cause of hydraulic system wear or
failure. Take care to keep contamination out of the hoses and fittings.
3.4 Plumbing the system – general
requirements
Before installing the steering hoses, please read and understand the
important DOs and DON’Ts below.
DO:
✓ Use only SeaStar or SeaStar PRO hose. Exception: you may use nylon
tube plumb the compensating line only.
✓Protect the hose from chafing, rubbing, and contact with assembly
screws or sharp edges of any type.
✓Route hoses through a protective PVC tube if possible. If not possible,
attempt to route the hoses so that they can be periodically inspected
for wear or damage.
✓Secure exposed sections of hoses every 12” (30 cm) or less.
✓Provide sufficient hose length in the splashwell to allow for cylinder
movement throughout the turning arc and the entire tilt range of the
engine(s).
✓Torque hose fittings to 15 ft-lb (20.3 Nm).
DON’T:
✗Use standard SeaStar hose with a SeaStar PRO power assist. Use only
SeaStar PRO hose.
✗Use hoses shorter than 6’ (1.8m) in length in the system.
✗Cut hose or attempt to install reusable fittings.
✗Install pipe sealant onto the hose side of a fitting.
✗Remove the protective end caps until the hoses have been routed and
are ready to be connected to the pump or cylinder.
✗Install hoses in an area where they will be exposed to high temperatures.
Areas to avoid are near engine manifolds and in engine compartments.
✗ Install hoses such that they contact electrical connections or are
exposed to battery acid or fumes from batteries.
✗Bend hoses tighter than a 3.5” (90 mm) radius.
✗ Allow hoses to hang free in an area where they could become a
safety hazard.

3-8 EN
3.5 SeaStar outboard front mount
cylinders and I/O cylinder
Outboard front mount cylinder part #’s:
HC5345-3, HC5347-3, HC5348-3, HC5358-3, HC5375-3, HC5445-3,
HC6345-3, HC6358-3, HC6845(S), HC6850
NOTE
Includes older models without -3 suffix.
I/O cylinder part #: HC5332
Connect hoses as follows:
Table 3-2.
Helm P/A Cylinder
SH1 C1 Port side
PH2 C2 Starboard side
R R
Helm pump model
and Displacement
Wheel
Turns
1.7 cu.in. per revolution 5
2.0 cu.in. per revolution 4
2.4 cu.in. per revolution 3.5
Table 3-3.
Single cylinder diagram3.5.1
Figure 3-4.
R
H1
H2 C1 C2
R
H1
H2 C1 C2
PRS
H1 H2
C1 C2
R
PORT STARBOARD