Webasto thermotop E User manual

Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
Installation Instructions
Marine Water Heaters
Thermotop C / E - Diesel 12v - English
Marine Comfort
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
Thank you for choosing Webasto Marine Central Heating
We are certain that you will enjoy many years of satisfactory
service from your Webasto product. Should you require any
assistance Butler Technik are always at your service.
Happy Boating!
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
Replacing other heaters
If this heater kit has been purchased to replace an
existing installation please see the important points
below. Otherwise continue to the next page.
Replacing other heaters
If you are removing an existing heater to fit this new
one then you must remove all the associated old
parts for that heater even if you are replacing a like
for like heater.*
This includes:
Fuel lines
Fuel pump
Exhaust system
Wiring harness
Controls / timers
Heater mountings
The heating circuit can remain intact, i.e. (radiators
and blowers etc) as long as they are installed in a
correct manner and resemble the installations
described on pages 16-22.
When all of the above parts are removed continue
with the new installation using the supplied new
parts.
*System components wear and performance can
decrease with age and should be replaced when
fitting a new heater.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
WARRANTY
Your Webasto heater is covered by a full
Manufacturer’s warranty covering defects caused by
faulty manufacture. This warranty period is 24
months from the point of purchase.
Claims cannot be accepted where faulty installation
has caused failure.
The warranty does not cover damage through water
ingress, external force, incorrect installation or
misuse.
Repairs, both during and after the warranty period,
should be carried out by an authorised Webasto
dealer only. Claims for repairs carried out by other
than an authorised Webasto dealer cannot be
accepted.
These conditions do not affect your statutory rights.
If you have any doubts as to who is your local
dealer, please do not hesitate to call Webasto. We
will inform you of your local dealer, who will be
pleased to give you any further information with
regard to your heater, or carry out any work or
repairs you may require.
All warranties are subject to the specific exclusions
detailed below:
Bulbs, line fuses, fuel filters, overheat fuses,
drive belts, glass panels, refrigerant,
receiver drier and lubricants. (Unless their
loss, damage or failure, has been caused by
a defect that falls within the scope of the
warranty cover as detailed above).
Glow plugs, burners, gaskets and seals normally
replaced during routine servicing, will not be
covered by the warranty, either to qualify for,
or within the duration, of any specific
warranty period.
Travelling time and mileage incurred in order to
affect repairs, (unless the installation of the
product is such that it cannot practically be
taken to an authorized repair centre).
These exclusions also preclude any claims for
labour associated with the diagnosis, or repair, of
any defects falling wholly within the scope of the
exclusions.
Warranty cover does not apply if the product was not
correctly installed (except as detailed above); is used
for any purpose other than that for which it was
designed; has been subject to misuse or neglect in any
way; has been modified without the prior approval of
Webasto product UK Ltd; has been fitted with non
genuine parts; or has been serviced or repaired other
than by a person approved by Webasto Product UK Ltd.
Warranty cover commences upon the date of purchase
of the product, or of the equipment into which the
product is installed from new. All warranty claims must
be presented with proof of purchase of the product.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
SERVICE
Don’t guess … seek advice!
Your local authorised Webasto dealer will be
pleased to help. Check first to determine
whether ‘call out’ charges may be applicable.
Regularly check your Webasto heating system
for the following points:-
• Corrosion on electrical terminals … clean
and spray with an inhibitor as necessary
• Clean running at the exhaust … if not, call
an authorised Webasto dealer
• Ensure that the exhaust outlet and
combustion air intake are ‘free’ and not
blocked or damaged … repair or replace as
required.
• Ensure sufficient water is in the header tank
if a tank is used, or check the system
pressure gauge if a the heater is fitted to a
pressurised system. Do not let either type
of system run dry.
• Periodically check the water specific gravity
and top up as required with a 75% water
25% anti-freeze mix .
• Run your heating system during the
summer, if only for a few minutes each
month, to check that it is operating
satisfactorily and to avoid ‘old’ diesel
collecting in the fuel lines. This avoids
acidity which can destroy components.
Every alternate season, it is recommended that
an authorised Webasto dealer tests the heater
system, and if required, any carbon deposits can
be removed from the heat exchanger.
If the heater takes in sea water or water from a
hose whilst cleaning the boat, - seek the advice
of a Webasto dealer immediately.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
TECHNICAL DATA
THERMOTOP C 12v
Heater Operation Thermotop C
Type Water heater with
evaporator type burner
Mark of Approval ~S289
Heat Output Full load
Part load 5.2kW 2.5kW
Fuel Diesel - EN590
Gas Oil - BS2869A2
Fuel Consumption Fuel load
Part load 0.59 l/h 0.30 l/h
Rated Voltage 12 Volt
Operating Voltage Range 9.75…15 Volt
Rated power consumption with circulating pump
(without vehicle fan) Full load Part load 32 W 18 W
Max. permissible ambient temperature:
Heater: - operation
- storage
Metering pump: - operation
-40º …+60ºC
-40º …+120ºC
-40º …+20ºC
Max. allowable working pressure (heat carrier) 0.4…2.5 bar
Capacity of heat exchanger 0.15 l
Minimum amount to be maintained in the circuit 4.00 l
Minimum volume flow of heater 250 l/h
CO2 content in exhaust gas (perm. funct. Range) 8…12.0 Vol -%
Dimensions of heater Length 214 mm
Width 106 mm
Height 168 mm
Weight 2.9kg
Circulating Pump 4847
Volume flow against 0.14 bar 500 l/h
Rated voltage 12 Volt
Operating voltage range 10.5…15 Volt
Rated power consumption 14 W
Dimensions of circulating pump Length 95 mm
Width 61 mm
Height 61 mm
Weight 0.3 kg
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
TECHNICAL DATA
THERMOTOP E 12v
Heater Operation Thermotop E
Type Water heater with
evaporator type burner
Mark of Approval ~S316
Heat Output Full load
Part load 4.2kW 2.5kW
Fuel Diesel - EN590
Gas Oil - BS2869A2
Fuel Consumption Fuel load
Part load 0.47 l/h 0.30 l/h
Rated Voltage 12 Volt
Operating Voltage Range 10.5…15 Volt
Rated power consumption with circulating pump
(without vehicle fan) Full load Part load 22 W 18 W
Max. permissible ambient temperature:
Heater: - operation
- storage
Metering pump: - operation
-40º …+60ºC
-40º …+120ºC
-40º …+20ºC
Max. allowable working pressure (heat carrier) 0.4…2.5 bar
Capacity of heat exchanger 0.15 l
Minimum amount to be maintained in the circuit 3.00 l
Minimum volume flow of heater 250 l/h
CO2 content in exhaust gas (perm. funct. Range) 8…12.0 Vol -%
Dimensions of heater Length 214 mm
Width 106 mm
Height 168 mm
Weight 3.0 kg
Circulating Pump 4847
Volume flow against 0.14 bar 500 l/h
Rated voltage 12 Volt
Operating voltage range 10.5…15 Volt
Rated power consumption 14 W
Dimensions of circulating pump Length 95 mm
Width 61 mm
Height 61 mm
Weight 0.3 kg
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
HEATER DIMENSIONS
105.5
104.5
213.5
1Fuel Inlet
2Water Outlet
3Exhaust Gas Outlet
4Combustion Air Inlet
5 Water Inlet
162.8
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
THE HEATER
The Thermotop Marine Kit incorporates a
diesel powered 5.2kW / 4.2kw water heater,
with a capability of a variable heat output,
down to a reduced heat level of 2.5kW.
Heated water is supplied to the vessel’s
heating system, consisting of household style
radiators and an option of domestic hot water
is also possible with the use of a Calorifier.
The heater burns diesel fuel supplied from the
vessel’s main tank, the correct amount of fuel
being measured and drawn by the dosing
pump, prior to delivery to the heater’s
combustion chamber.
On arrival in the combustion chamber, the fuel
is vaporised off a unique ‘Ferro-Tech’ burner,
initially being ignited by a glowpin. Following
starting the heater, combustion is sustained by
the continuous vaporisation of the metered
fuel delivery.
Combustion takes place within a sealed heat
exchanger, and exhaust gasses are ducted to
the vessel's side or transom, via a stainless
steel flexible pipe and skin fitting.
Meanwhile the heater’s integral water pump
circulates cool water from the heating system
into the heat exchanger, where it is heated
and re-introduced hot into the heating system
to heat the radiators etc.
Operation of the heater is via a 3 event digital
timer, which can be sited in the main cabin
area. The timer also has an “instant heat”
facility.
If blower boxes are used, an optional thermostat
control system is available to regulate the cabin
temperature.
For maximum safety, the heater has various
sensors which will shut down the heater should
they be activated.
These heaters are not solely used in boats; but
are supported by a pedigree of military, truck,
car, luxury coach and a variety of other applica-
tions.
The Thermotop C / E marine kit is designed
specifically for marine users, incorporating the
high technical specification required for The
Inland Waterways
Combustion Air Inlet
Fuel inlet
Cold Water Return
Hot Water Outlet
Exhaust Gas Outlet
Electrical Connections
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
POSITIONING OF THE HEATER
The heater requires a dry, protected area, which
will not be adversely affected by seawater,
excessive vibration or fumes.
The location of the heater must be well clear of
any gas storage or delivery lines. When
choosing the position, bear in mind stowage,
conduits and service access points, steering gear
linkages etc. It is also important to consider the
required installation features for the Thermotop
C / E heater.
1. Exhaust maximum length
2. Exhaust outlet point
3. Combustion air maximum length
4. Combustion air inlet point
5. Access for heater pipes
6. Fuel pick-up point
7. Electrical supply
The engine room is a favoured position, where
fuel, combustion air and access to the hull for the
exhaust are all at hand. As an alternative, fit the
heater in a cupboard in the galley, ducting the
combustion air inlet to a point within the vessel
not usually occupied by passengers. Avoid
impinging upon stowage space or placing the
heater where sails may rest on the hot exhaust
system. Mount the heater level so as to avoid
forming air pockets inside the heat exchanger.
The heater will be shipped with a serial number / ID
label attached on one side and a duplicate spare on
the other. Please mount the spare label on the
other side of the heater or somewhere on the
heater were it is visible.
Figure 1
Typical Water Heater System
Do not mount the heater as shown below
If the heater is mounted in these orientations air will be trapped inside
the heat exchanger.
Permissible mounting orientations are shown below
0°<> +90°
0°<> -90°
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
EXHAUST SYSTEM
Length of the combustion air inlet & exhaust lines in
total:
With exhaust silencer: max 2.0m
Without exhaust silencer: max 5.0m
Exhaust Connection - Typical
Create a swan neck in the exhaust to prevent water
ingress. The heater requires a dry exhaust, not
water injected.
Minimum bend radius: 50mm
Total bends
Combustion air pipe: max 270°
Exhaust pipe: max 270°
For every 90°of bend in combustion air and exhaust
pipes the exhaust system total length must be
de-rated by 500mm.
The exhaust from the heater must not be
connected to any other exhaust system.
Route the flexible exhaust, securely attached in such
a way that the heat cannot affect
adjacent plastic piping, electric cables etc.
The exhaust pipe should be wrapped in the woven
glass protective sock and secured with stainless ties
supplied with the kit. If addition protection is re-
quired, over-wrap with woven glass tape available
from your Webasto Dealer.
Exhaust Insulation
Apply Sealant to
Underside of Face
60
52 50
Not To Scale
Drillind Dimensions
Thermo 90
EX
Silencer
Swan neck
created in
exhaust
Flexible Exhaust with
attached Lagging
Heater
Hull
Turn Inwards & overlap
Lagging 50mm to prevent
fraying
Over sleeve using Woven Glass
Lagging if extra protection is
required
Secure Lagging with
'Worm Drive' type clamps
Leave sufficient exposed exhaust
to allow exhaust clamp to be fitted
The skin fitting is normally fitted on the transom or
cockpit combing. The hull side is acceptable for motor
boats, but bear in mind the bow wave line and beam
sea risk. It must also not point in the direction of travel,
or be susceptible to high land wind pressure, which may
blow out the flame within the heater.
Measure the diameter of the skin fitting to be fitted and
cut the hole using a hole saw.
A suitable pilot hole should be drilled first!
 Do not fit the skin fitting below the water line.
 Do fit the skin fitting as high as possible to stop
water ingress
 Do make sure that exhaust clamps are tight to
avoid gas leakage
 Do make sure the exhaust glasses cannot reach
the combustion air intake
 Do not cover the exhaust with the heater running.
We recommend the application of a suitable high
temperature sealant being used on all the exhaust
connections sufficient to fill the corrugations in the
flexible pipe ONLY but not enough to block or impair the
exhaust system.
We recommend the use of Webasto PC diagnostics to
verify the exhaust emissions of the installation. Your
local Webasto agent can supply this instrument or may
be able to offer a commissioning / calibration service.
For CO2 emissions refer to the table of specifications in
this book.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
FUEL CONNECTION
If you are installing the heater to Lloyds
specifications, Specialist advice should sought.
The Fuel system conforms to ISO 7840 & the Inland
Waterways specifications when installed correctly
as detailed. Always ensure only clean fuel is used.
The heater is designed to run on EN590 Diesel &
BS2869A2 Gasoil.
The use of fuels containing high levels of sulphur,
water or other contaminants may increase the
service interval required.
Several specific regulations apply including the use
of flame resistant fuel pipe such as copper pipe,
and fire resistant fixings. Use a sharp pipe saw and
NOT a hacksaw if the supplied copper pipes are
shortened. If the pipes are shortened the pipe ends
must be
re-flared with a suitable flaring tool as per the
picture below. Ensure afterwards that the bore of
the pipes are still 2mm. Use a 2mm drill bit as a
gauge. Connect the flared copper pipes with the
small black ISO7840 hose pieces to the Fuel Pump,
Heater, Standpipe and other fuel system parts that
have a barbed nipple connection and secure with
worm drive clamps.
The best technique is to fit the rubber pipes on to
the standpipe, fuel pump and the heater nipples
and then insert the copper pipe flared ends fully into
the other ends of the rubbers. The reason for this is
to ensure there are no gaps inside the rubber pipes
that could harbour air pockets as shown below.
Apply a dab of diesel to the pipe ends before
assembly. This will make the installation easier and
reduce the likelihood of the bore of the rubber pipe
being torn and causing a blockage.
Follow the diagrams below for connecting the fuel
supply and positioning the components, noting the
mounting parameters, for the fuel pump, which are
critical to ensure correct operation of the heater.
Mount the fuel pump using the “P” clip according to
Pump Diagram. Ensure the correct direction of flow is
observed. Depending upon the quality of fuel used and
the point where the fuel is extracted from the vessels
fuel system, an additional water
separator and or fuel filter may be required prior to the
dosing pump.
Fuel Supply System - Typical
Tank
Heater
Ball Valve Fuel Pump
Fuel Filter &
Water Trap
The Ball Valve, Filter / Separator are optional and may
not be part of your kit. All optional parts
mentioned are available from your Webasto Dealer.
The copper fuel pipe used in the system should be:
2 mm Inside Diameter
5 mm Outside Diameter
The copper pipe supplied with the kit meets this
standard.
Ensure that the 2mm I.D. - 5mm O.D supplied copper
pipe is used.
If you fit any additional filter or valves in the fuel
system make sure the pipes / hoses are flared copper
and are connected with ISO7840 50mm long hose
sections clamped at each end.
5 mm2 mm
Fuel pipe dimensions
Flared end of copper pipe
If other pipe fittings are needed due to different fuel
supply arrangements i.e. in-line filters or water
traps etc other than those supplied these can be
obtained from your Webasto Dealer.
Illustration of how to insert a copper pipe into a rubber joiner.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
The suction hose length, (Fuel Tank to Fuel Pump)
including the pick up pipe length, (if applicable)
should be no longer than 1.20m, use the 1.2m
copper pipe supplied.
The maximum height of the Heater above the Fuel
Pump should be no more than 3.0m.
The Fuel Pump Must NOT be mounted above the
heater or any exhaust pipe.
All fuel lines must be correctly installed and securely
mounted and protected against heat, impact and
abrasion damage.
Tank
Heater
≤1.20m ≤8.80m
Fuel System - Pipe Maximum Lengths
Fuel Pump mounting orientation is critical to correct
performance. Mount horizontally using anti vibration
clip with electrical connector inlet orientated
downwards as shown in drawing below. Do not
mount close to heat sources, (engines or exhausts).
Ensure pump is mounted to avoid mechanical
damage. The pump must not be mounted more
than 3m below the heater. Refer to the drawing
below for the correct heights etc.
FUEL CONNECTION
(Continued)
Direction of Fuel Flow
Fuel Pump Orientation
Ensure the fuel lines are installed securely with rubber
lined P-Clips and routed in such a way that they will not
suffer from mechanical damage.
Do not install the fuel lines adjacent to any heat source.
Do not clip the fuel lines to any exhaust system. Do not
clip any wiring harness or cable to the fuel lines. When
route the pipes try to avoid forming tight angles in the
copper pipe. All bends must be gentle and sweeping
with a large radii.
Fuel System - component heights
Ensure the fuel lines are installed securely with rubber
lined P-Clips and routed in such a way that they will not
suffer from mechanical damage.
Do not install the fuel lines adjacent to any heat source.
Do not clip the fuel lines to any exhaust system. Do not
clip any wiring harness or cable to the fuel lines. When
route the pipes try to avoid forming tight angles in the
copper pipe. All bends must be gentle and sweeping
with a large radii.
When fitting the optional fuel filter (Sub-kit 4110766A).
mount the fuel filter in between the standpipe & fuel
pump. Observe correct orientation as shown below! The
mounting bracket should be installed as shown below
with the bracket holes sitting on top of the hose tail flats.
When fitting the hose tails to the filter body DO NOT use
PTFE tape! Use a liquid sealant e.g. Loctite 572
Fuel IN
from Tank Fuel OUT
to Heater
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
When fitting the Webasto standpipe drill the fuel tank
using a “25mm” hole saw, or using a cone cutter in
preference to filing. Note: before drilling, grease the
top of the fuel tank around the intended drilling area to
collect any swarf which will be present.
Ensure that the aforementioned guidelines are referred
to when choosing the positions of components, such
as the heater and fuel pump.
Link the fuel supply from the standpipe to the fuel
pump and from the pump to the heater using the
copper Fuel pipe with the black hose sections as
unions as described previously. Remember to Flare
the copper pipe ends if any pipes have been
shortened. Remove any burrs from the Fuel pipe using
a small file and blow any swarf out of the pipes prior to
fitting.
Lay the fuel pipe straight, preferably running gently
upwards towards the heater to ease the bleeding of
any air in the fuel line. Avoid tight radius pipe bends as
these cause a resistance in fuel flow. It is preferable to
have a wide radius bend.
Securely clip the pipes at frequent intervals, away from
any heat source.
Please note if any other pipe fittings or inline Valves or
Filters etc are fitted into the fuel line that contain
compression fittings make sure they do not contain
brass olives as these are too brittle.
Only use copper olives. When using copper olives
there is less chance of distorting the copper pipe.
If the supplied standpipe is too long for the fuel tank
ascertain the correct length, (normally 4~5 inch from
tank bottom) then using a very sharp knife blade score
the pipe diameter and snap the excess off.
Ensure the standpipe is leak free after installation.
Webasto Standpipe
FUEL STANDPIPE
CONNECTION
It is possible to use instead of the Webasto standpipe
a piece of pipe that complies with the Webasto
standard of 5mm OD & 2mm ID. Below is a picture of
how this can be achieved using readily available parts.
A suitable hole needs to drilled to suit either a through
bulkhead connector or a weld in place threaded 'bush'.
If a bulkhead connector is used, use bonded washers,
(doubtless seals) between the metal of the tank and
the connector shoulder.
If it is decided to weld in a bush, make sure the male
insert has a tapered thread.
Thread a piece of pipe to the specification detailed
above through the fitting into the fuel tank.
Bend at 90 degrees taking care not to kink the pipe
and collapse the internal bore.
Tighten up the nut and olive to secure the connection.
Do not over tighten the fitting and crush the pipe.
A fuel resistant thread sealant must be used on both
options. Do not use PTFE tape!
Ensure the penetration into the fuel tank is leak free
afterwards.
Please ensure that the
pipe used complies with
the Webasto fuel pipe
standard of:
5mm OD
2mm ID
Use bonded washers on
the bulkhead connector.
Alternative Standpipe
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
COMBUSTION
AIR INTAKE
Do not extract combustion air from passenger
compartments.
The heater is supplied with a length of
combustion air pipe. This should be placed in
such a position to provide dry, cool air to the
heater unit. Always fit pipe!
If mounted in the engine room, ensure that no
foreign bodies enter the intake pipe.
Avoid mounting the pipe in such a manner that
drive belt dust could enter the heater!
Do not let the pipe hang down if a potential
exists for bilge water to enter the pipe if the
vessel heels over in heavy seas.
The combustion air pipe supplied is the
maximum length permitted and should not be
extended.
Do not extract combustion air from the vessel’s
engine air intake or filter system.
Fit the round black combustion air silencer to the
end of the pipe and securely mount.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
WATER PIPES
Non-Pressurised System
100mm
Highest Radiator (in system)
20mm Water Pipes
15mm Water Pipes
Calorifier
Heater
Radiator
Fan Assisted
Warm Air Heater
Header Tank (must be highest point in system)
TYPICAL WATER CIRCUIT WITH HEADER TANK
The Thermotop C / E marine kit includes a Water Header Tank and rubber hoses suitable for
connection to 22mm pipe work. As numerous systems are used on vessels, no other pipe work is
supplied as standard.
Pictured below is a Thermotop C / E marine kit installed as an un-pressurised independent closed
system, an example is shown below. However, with modifications it can be used to provide engine
pre-heating or to operate an independent un-pressurised system.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
PLUMBING OPTIONS
WATER
Heater
Header
Tank
Radiator
Or
Blower Box
Radiator
Or
Blower Box
Pump
Calorifier
Filling point
Example 2. Gravity system with a two pipe header tank.
Heater
Header
Tank
Radiator
Or
Blower Box
Radiator
Or
Blower Box
Pump
Calorifier
Filling point
Example 1. Gravity system with a one pipe header tank.
Heater
Header
Tank
Radiator
Or
Blower Box
Radiator
Or
Blower Box
Pump
Calorifier
Filling point
Example 3. Gravity system with a two pipe header tank and bypass valves
The hot water plumbing arrangements can use typical domestic components, i.e. pipe, elbows, tees etc. The
heating system flow and return lines, (called the 'spine') need to be made up with 22mm OD pipe, Copper, Hep2o,
Speedfit etc. The heater is supplied with a length of 22mm ID rubber hose, cut this hose to suit and interface into
the spine with 22mm pipe and jubilee clips or use threaded hose tails connected to push fit fittings or compressions.
The radiators can be connected as shown using 22x15x22 unequal Tees. Good plumbing practice Rules! Try to
keep elbows to a minimum, use swept bends where possible. Try to ensure a gentle rise on the flow and return
pipes to ease the commissioning process as air locks in pipe work installed behind joinery can be problematic to
overcome! These rules apply to both non-pressurised and pressurised systems
Examples of typical non-pressurised gravity plumbing arrangements.
A
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
PLUMBING OPTIONS
WATER (non-pressurised)
All these systems are filled via the header tank with a mixture of 75% Water & 25% Glycol.
Example 1. Gravity system with a one pipe header tank.
By far the simplest gravity fed system.
Quick and easy to fill up with coolant.
The header tank is connected via an equal T piece in the return line of the heating spine within
about 30cm of the coolant pump inlet.
This is the quickest and most cost effective system to install with regards to material costs.
However, it is by far the most onerous system to commission.
The main drawback of installing a one pipe header tank system is the difficulty in removing the
air from a dry system during commissioning.
Example 2. Gravity system with a two pipe header tank.
Similar to the first system but instead of relying on air to naturally travel up one single pipe via a
T piece, this system deliberately circulates water through the header tank to remove large
amounts of air. The tank is plumbed into the system as in example 1 above but instead of the T
piece, the pipe is cut and an elbow is fitted on each end and two pipes are run vertically up to
the header tank.
With this type of arrangement all the large pockets of air will be taken from the system.
There are two problems with this system, firstly, when the visible air bubbles have been
removed there is no reason to waste energy pumping water up to the tank and then back down.
The header tank ends up being a radiator! Secondly, the water turbulence is constantly
introducing micro bubbles into the water. These air bubbles act as an insulator and reduce the
thermal efficiency of the water that’s being circulated.
Example 3. Gravity system with a two pipe header tank and bypass valves
The header tank uses two vertical pipes, one in and one out as in the above example
However, the two vertical pipes connect to the spine via 2 Tee pieces.
In between the two Tees, a ball valve is fitted.
The reason for this is to speed up the air purging as in example 2, but to also negate the
formation of micro bubbles.
How it works. When the system is dry and being commissioned we need to get as much air out
of the system as possible so we Close Valve A. This forces the water up into the header tank
and back down to the circulation pump and is a good performance indicator of the air / water
content during the commissioning process. When all the visible air bubbles have been removed
Open Valve A. The micro bubbles will now eventually vent from the water and into the header
tank. As opposed to example 2 the header tank in this system no longer acts as a radiator or
imposes any additional flow resistance.
This is the most efficient non-pressurised header tank system.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
Heater
Radiator
Or
Blower Box
Radiator
Or
Blower Box
Pump
Calorifier
Expansion
Vessel
Filling Loop from Vessels cold pressurised water
supply. Note 2 ball valves and one check valve.
AAV AAV
PV
PLUMBING OPTIONS
WATER (Pressurised)
Examples of typical Pressurised plumbing arrangements.
Heater
Radiator
Or
Blower Box
Radiator
Or
Blower Box
Pump
Calorifier
Expansion
Vessel
Filling Loop from Vessels cold pressurised water
supply. Note 2 ball valves and one check valve.
AAV AAV
PV
Example 1. Typical Pressurised system using Auto Air Vents - (AAVs).
Example 2. Typical Pressurised system using Auto Air Vents - (AAVs) & Spirovent
Spirovent
Note the inclusion of the Pressure Relief valves, (marked as PV). One of these should be mounted in
the hot water outlet pipe no more that 30cm away from the heater. Preferably at a high point.
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Webasto Part Number : 4110310A
Issue No: 02 : 10th November 2010
Matthew Millard
In the interests of continued development, we reserve the right to change
specifications without prior notice © Webasto Product UK Limited
Marine Comfort
PLUMBING OPTIONS
WATER (Pressurised)
Example 1. Pressurised system with AAV's
This is the most efficient, reliable and robust system and is most suitable for a marine
installation. There is no need for a header tank to be fitted and therefore radiators can be
installed at any height in any position. This is especially useful when installing a system in a
boat with decks on different levels.
The air purging and filling process is very easy and straight forward.
There is no need to top up any header tanks.
To charge the system a 'filling loop' or connection to the vessels pressurised water system is
required. As indicated in the drawing, two ball valves and a non return valve are required so as
to prevent any glycol contamination of the vessels cold water supply.
An expansion tank is connected via a T piece to the return spine close to the circulation pump
return. This tank has inside a rubber bladder that should be delivered pre charged to 3 bar.
In between the above mentioned tank and pump, the 'filling loop' is Teed into the return spine
also, as seen in the diagram.
A pressure gauge is fitted to indicate the system pressure.
When filling this system for the first time proceed as follows.
Pre mix the water / glycol.
Remove one of the vent caps from each radiator, (the threaded boss that holds the bleed screw
on the radiator). One radiator at a time.
Make sure both the valves on each radiator are fully open.
Carefully fill each radiator as much as you can with this pre mixed fluid and replace the
threaded boss on each radiator. Now the system should be almost full.
With the filling loop connected open both the valves on the filling loop pipe and watch the
pressure gauge. Fill to 1 bar (14.5psi). You will probably hear air escaping from the auto air
vents, this is normal.
Now the system is under pressure, open each radiator in turn and bleed any trapped air.
Recharge and repeat as necessary.
Switch on the heater so the pump is circulating and check the pressure gauge and recharge the
water system up to 1 bar if required.
Ensure both the valves on the filling loop are turned OFF when filling has been completed.
DO NOT overcharge the system above 1 BAR (14.5 psi) when cold.
It is normal when the system is up to full operating temperature for the pressure to rise up to 1.5
BAR (21.75psi) ± 5%.
Example 2. Pressurised with AAV's & Spirovent
Exactly the same system as above but with the addition of a Spirovent unit that will remove the
micro bubbles quicker than AAV's alone.
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