Viking VSC 61 FY User manual

Table of Contents
•Preliminaries
•Introduction
•Vessel Operations
•Fuel System
•Propulsion System
•Electrical System
•Electrical Safety
•Bilge Pumps
•Heating / Cooling System
•Fire Emergency
•Corrosion Protection
•Subsystems
•Water System
•Sanitation System
•Vessel Care
•Addenda
•Service Numbers Directory
VSC
61 FY
Owner’s Manual
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Owner’s Manual
Aircon / Heating - 66 Viking Sport Cruiser 61FY
v1.0
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Cooling / Heating System
This chapter describes the Cruisair heating/cooling system
and, briefly, how it works. Instructions are given on basic
operations and troubleshooting apparent problems. Major
components are identified and located.
Major Topics:
How it works 67
Aircon components (location drawing) 68
Compressor units 69
Evaporator and blowers 70
Operating the system 71
Troubleshooting the system 72
The Publisher’s Statements on
page i of this Owner’s Manual apply
to this chapter. Please read before
proceeding.
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TABLE OF CONTENTS

67 - Aircon / Heating
Viking Sport Cruiser 61FY
Owner’s Manual
v1.0
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How it Works
Your VSC 61 Flybridge Yacht is equipped with a Cruisair
“Direct Expansion” system (so-called because refrigerant,
rather than tempered water, is piped to individual expan-
sion units in the cooled spaces). This is a complete sub-
system that includes many items. Unlike home air condi-
tioners, it uses seawater to absorb the heat removed from
the vessel.
The seawater pump Aand pickup Bare installed below
the galley floor. The pump is specially-built to run for days
on end, and it is very quiet. A magnetic drive couples the
motor to the centrifugal pump, C.This pump cannot suck,
and is NOT self-priming, so water must flow freely to it
(hence its location below the waterline). The system is
designed to be self-draining (of seawater) with hoses go-
ing uphill, in and out of the pump until just before the
overboard discharge; from that point hoses go constantly
downhill. NEVER MOVE THE HOSES. The self-draining de-
sign makes it easy to winterize the system if the vessel is
out of the water.
If air is drawn in, the pump can become air locked. This
could happen if the vessel is removed from the water – then
bleeding of the pump may be needed. Avoid this by closing
seacock Bbefore lifting the vessel and open it again when
the vessel is back in the water.
Seawater supply passes through strainer D. Like all such
strainers, it must be checked for weeds and debris on a
regular schedule. If any of the units do not cool as they
should, the strainer is the first place to look for the source
of the problem. The rotating impeller in the pump is lubri-
cated by seawater. Thus, if debris blocks the water flow
the bearing surfaces will overheat, which may lead to pump
failure.
The seawater pump has a manifold Efeeding three hoses F
which supply seawater to the 4 condenser units (com-
pressors).
Seawater is pumped through hoses Finto the double wall
coils G on top of the condenser. A reciprocating-type com-
pressor compresses R22 refrigerant gas from about 75
psi to 275 psi, making it very hot and dense. It then passes
through the double walled coils Gwhich envelop the gas
pipe with cool seawater. The hot gas warms the seawater,
thus giving up heat and becoming cool. The seawater,
which is now hot, is pumped through hoses Hinto a mani-
fold then overboard through the starboard engine exhaust.
The cooled gas is filtered and dried Lthen pumped in
insulated pipes M to the various expansion units in the
living spaces.
Note:- All items shown are accessed via the hatch in the
galley floor.
36,000 BTU
B
D
B
C
E
F
G
A
D
H
L
M
F
H
F
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Owner’s Manual
Aircon / Heating - 68 Viking Sport Cruiser 61FY
v1.0
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S-Seawater Pump - Draws
seawater thru a bottom fit-
ting and strainer and sends
it to the four condenser units.
C-Reverse Cycle Direct
Expansion Condensers -
These 4 units compress re-
frigerant, causing it to re-
lease heat, which is trans-
ferred to seawater flowing
thru and then discharged
overboard (via port engine
exhaust). Compressed re-
frigerant goes to evaporator
units in the cabins to provide
cooling. A reverse cycle valve
enables the system to heat
cabins as well.
C+is 36,000 BTU;
others Care 7-10k BTU.
All 4 condensers are under
the galley floor.
E-Evaporator Units - These
6 units receive the com-
pressed refrigerant and
quickly decompress it
through a heat exchanger
coil, thus taking up heat from
the cabin air. Thus the air is
cooled, and the now hot re-
frigerant circulates back to
the condenser units where
the acquired heat is trans-
ferred to seawater during rec-
ompression.
Aircon Components
Seawater p/u
Salon
Deck Lower
Deck
12K
10K
12K
12K
7K
10K
C
S
C
+
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69 - Aircon / Heating
Viking Sport Cruiser 61FY
Owner’s Manual
v1.0
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Compressors
The four compressors and the seawater pump are under
hatch #13 in the galley, A. To gain access to this, and also
the water system, lift hatch Aand put it safely aside. Then
remove the large white plastic storage bin filling the hatch
space. Lift it up and also put it safely aside.
All of the equipment is now visible. The compressors are
on shelves, but other components are on the floor. Space
here is very limited so great care must be taken not to
stand on or move any equipment. While you can access
the strainer from here, it is easier to check it for weeds
via the lift-up stair B(hatch #12) near the washer. To op-
erate the thru-hull valve, lift up the small hatch (#11) in
front of the washer.
Check for water leaks around the seawater hoses and
hose clamps. Although double clamped, the hose sof-
tens over time and leakage is possible. An integral drip
pan under each compressor drains to a small grey water
sump under hatch #10 in the starboard cabin – from there
the condensate is pumped overboard.
Total rated system capacity is 63,000 BTU. Compressor
ratings are:
•One 36,000 BTU unit C1supplies three 12,000 BTU
evaporators in the Salon and dinette.
•One 10,000 BTU unit C2supplies a 10,000 BTU evapo-
rator in the forward cabin
•Another 10,000 BTU unit C3supplies a 10,000 BTU
evaporator in the starboard cabin.
•One 7,000 BTU unit C4supplies the evaporator in the
port cabin.
There are six evaporator units (see next page) throughout
the vessel. Each has expansion valves which allow the high
pressure refrigerant gas to expand, causing a sudden drop
in pressure and a resulting drop in its temperature to below
freezing. The cold refrigerant then goes through the coils of
a type of radiator as a blower moves air across the coils,
cooling the air very quickly. A reverse cycle valve is installed
to reverse the process, and thus deliver warm air.
The system operates effectively, cooling well in seawater
up to 80°F and heating well in seawater down to 42°F.
Photo Dshows typical discharge from the compressors
when the system is running. Knowing “normal”, you can
judge if the seawater filter is restricted by weeds etc. When
the seawater pump is running all four compressors have
seawater flowing though them, whether they are operat-
ing or not. This is a free flow system and water must flow
when the seawater pump is running. A hose from each
compressor goes along the side of the hull and ends in a
manifold. A single hose from there discharges into the
starboard engine exhaust tube.
←
Discharge
Discharge
Typical
discharge
Suction
Suction
Hatch #12 - lift stair
Hatch #13
Refrigerant gas lines
to/from evaporators
B
A
C
1
C
4
C
3
C
2
R
C
4
D
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Owner’s Manual
Aircon / Heating - 70 Viking Sport Cruiser 61FY
v1.0
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←
Not cooling?
A buildup of dust is
the most common
cause of poor cooling
performance. Inspect
and clean often.
F
←
←
Conditioned air outlets and returns
Photos above show typical locations of outlets/inlets
that facilitate circulation of heated or cooled air in the
living spaces. Cis outlet; Ris return.
conditioned air out
conditioned air out
air returns
air returns
conditioned
conditioned
air out
air out
→
Evaporators and Blowers
The six evaporators (expansion units) Aare located in
spaces that are normally an enclosed compartment, and
usually not far from a floor level air return grille R. The
photos here show typical installations of evaporator units
– under beds or couches, and under the bridge stairs.
A boat is more commonly used in hot weather so the
prime need is for air conditioning. Chilled air is forced up
to outlets near the ceiling C. Being cold, the conditioned
air falls and circulates to the ground where the suction of
the return air Rpulls it back in to the evaporator to be
recooled and recycled back to the ceiling area.
Evaporators have an integral blower Bto suck in air through
a grille R, a filter screen F, and then into the evaporator
unit A.Within the unit, cooled (or heated) refrigerant gas
goes into an expansion valve behind the evaporator, it
deploys through the coils and returns to the suction side
of the condensing unit (compressor) to start a new cycle.
In cooling mode,the temperature of incoming air is low-
ered about 20°F as it blows over the chilled evaporator
coils. The chilled air is blown into an insulated pipe Eand
discharged via an outlet duct C to cool the vessel.
In reverse cycle cold floor-level air is heated, the evapora-
tors warm the air, and blow out outlet duct(s) C.
Sensors Smonitor return air temperature; do not move them.
Below each evaporator, an integral pan catches dripping
condensate. It drains to the grey water box from where it
discharges overboard. This is why it’s essential to have on
the SHOWER DISCHARGE PUMP breaker if the A/C is operating.
Behind every return air duct there is a filter, either inside
the duct or attached to the
evaporator unit. Filters
quickly collect dust, and it
gradually blocks off air flow,
resulting in very little air com-
ing from the outlet.
It is absolutely necessary to
keep return air filters clean.
Cleaning of the filters should
be scheduled – remove and
clean them every 2 or 3
weeks when the vessel is in
use. Vacuum then rinse in
warm water. Let dry before
refitting.
Do not run the A/C without dust
filters in place. Dust will clog up the
evaporator coils and major work will
be needed to remove it.
←
B
C
E
F
A
R
S
AB
A
R
C
F
R
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71 - Aircon / Heating
Viking Sport Cruiser 61FY
Owner’s Manual
v1.0
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Operating the System
The four condensing units share a common seawater in-
put fed by the seawater pump. This pump starts when
any A/C breaker is switched on.
To distribute air more evenly, evaporating units in some
cases have more than one outlet. Similarly, ttoilets are
supplied with air ducted from a unit in the adjoining cabin.
Procedure
Switch on breakers Qto T, or only the ones needed. Se-
lecting any of the units powers up the system. The sea-
water pump starts automatically and seawater flows
through all four condensers, even if only one is selected.
Also, the SMX controls become active. After starting the
system, check voltage under load, and check that over-
board discharge at the starboard exhaust is normal.
Note:- The panel switches are CIRCUIT BREAKERS, and if
overloaded through low AC voltage they may trip.
SMX II controls
On system start-up: If the individual SMX II controls were
not switched off, they assume the settings of the last
time they were used.
Indicator lights show compressor mode: COOLING or HEATING.
The setpoint indicator lights when temperature is reached.
Press SET key to display current setpoint (the tempera-
ture you wish to maintain). To change setpoint, use the UP
and DOWN keys and select the temperature required.
To select automatic changeover from heat to cool, press
HEAT and COOL both at the same time.
To switch the system off, push the OFF key.
It is best to leave fan speed in automatic, unless you wish
to run the fans only without the compressor running. In
automatic, when the compressor is running, as the set-
point is reached fan speed slows down. Once the com-
pressor cycles off, the fan runs in slow speed. AUTO fan is
strongly recommended.
For further information consult your Cruisair Direct Expansion
Users Guide and the SMX Series Control System guide.
Electrical load management
If shore power voltage is low power can be conserved by
running only the compressor serving the area you are in.
The cooktop and the A/C are the biggest users of power.
Cooling
indicator
Set point
indicator
Up/Down
keys
COOL key
OFF key
Fan indicator
Heating
indicator
SET key
TEMP key
HOT key
Fan key
SLOW-FAST
keys
HeatingCooling
Down Set Up
Run Off Aux. Heat
Slow Fan Fast
Manual Mode
Temp.
SMX II
Set point &
system error
SMX II Keypad
In addition to providing all the controls necessary for
climate control in the living spaces, the SMX units also
display error codes (please reference your SMX manual
for details). System faults are displayed as a code on
these SMX controls. For example, it will show if the
sea water strainer is partially blocked with weeds.
Aircon / Heating Breakers
Activate condensers selectively by breakers Qto T.
They also power the vessel’s six evaporators.
Q
R
S
T
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Owner’s Manual
Aircon / Heating - 72 Viking Sport Cruiser 61FY
v1.0
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Check voltage and
load – 240 volts
Reduce load if a A/C
breaker. With an Iso-Boost
transformer and 100 amp
service, low voltage should not be a problem, but you
may be unable to switch on all units. Remember as
voltage decreases amperage increases.
The SMX units also display error codes (see SMX
manual for details). System fault codes are displayed
if, for example, compressors are overheating because
the seawater strainer is partially blocked with weeds.
To clean the seawater strainer. . .
•Switch off ALL breakers for the A/C system.
•Close seacock S. Have a dish handy to dump sea-
water and debris from the strainer into it.
•Loosen the four bolts holding the cap B.Seawater
will come out. Avoid getting seawater into the com-
partment by having an absorbent cloth around the
cap. Ease up and remove bolts and cap.
•Remove the internal screen. Clean out all weeds
and other debris.
•Replace the screen and cap, tighten down the nuts.
•Open the seacock S; the strainer should quickly fill
with seawater. Check the cap for leaks. If OK, switch
the system on.
•Check again to ensure there are no leaks.
•Check that discharge
flow is normal.
Regularly check the A/C strainer
for weeds and other debris.
Remember – this is below the
waterline! So shut the seacock.
Troubleshooting the System
One of the advantages of a direct expansion system is its
simplicity. It depends simply on:
•an unobstructed supply of seawater,
•correct voltage,
•free flowing air supply to the return air grilles, and
•unobstructed air discharge ducts.
Any one of these items that is not up to par will give you
a problem.
If the air conditioner is running in weedy water, the strainer
can quickly fill with weeds. Don’t neglect to regularly check
the A/C strainer for weeds, sea urchins and other debris. If
anything gets through the strainer it can slow down the
magnetic drive to the pump. However, the strainer will not
stop sand, and that may damage the seawater pump. Over
time, sand in the water can erode the double wall pipe
above the compressor.
Also be aware that suction at the thru-hull may attract
plastic junk in the water, preventing seawater getting to
the pump. Get to know the normal appearance of dis-
charge from the compressors through the engine exhaust
so you can tell if flow is reduced.
Do NOT obstruct the return air grilles with furniture, cush-
ions or newspapers. If air cannot get through obviously
the air in the cabin cannot be cooled or heated.
The same thing happens if the air filter screen behind the
return air grille is not cleaned – very quickly dust builds
up, starving the system of free flowing air. You should
check screens every two weeks if the vessel is in con-
stant use, monthly if not.
Check the dock voltage, if it is low, below 205 volts, you
should be selective in how many units you run or, if cool-
ing, set them at a higher temperature.
If you leave the system on when you are away for a few
days, arrange for someone to check that it is operating
properly (and leave the SHOWER DISCHARGE PUMP on).
These are very simple checks – if they are done the sys-
tem will perform as designed, and maintain a constant
pleasant temperature throughout the vessel.
S
B
S
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