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STEAM
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VIEW SPARES
Introduction :
The new series pressure boilers were introduced
in March 1996 and were amongst the winners of the CEDA awards the
same year. The series were designed to be stylish in appearance
and simple to service.
This manual has been designed to be a guide for service engineers.
It includes descriptions of all serviceable parts and an exploded
drawing of a complete machine, sub-assemblies and wiring diagrams.
All models are constructed in the same way, but
vary in size.
Principle of Operation :
After switching on, the power light will illuminate
and the ready and service lights will flash four times simultaneously.
The machine will then look for water at the bottom level sensing
probe. If water is not detected at the probe, the machine energises
the solenoid valve to allow water into the boiler. If water is not
detected at the bottom probe, e.g. the probe is scaled up, the machine
will fill to the top probe. If this occurs, the service light will
flash twice and then pause. The machine will function normally but
continue to indicate that the bottom probe has not been detected
(See chart on page 12).
If the bottom or top probes are not detected within 4.5 minutes,
the machine assumes that there is a problem with the water supply,
and will flash the red service light 6 times to indicate that the
boiler has failed to fill within the allotted time.
When the water reaches the probe the machine will
switch on the heating element(s). When the machine has reached boiling
point, pressure will start to build. When the pressure on the pressure
gauge reaches 14 p.s.i. the ready L.E.D. will illuminate and the
solenoid will start to pulse water into the boiler. The element(s)
do not switch off during filling, therefore if water does not enter
the boiler correctly the steam pressure will increase and switch
the override pressure switch off at 18 p.s.i. and all the lights
will go out.
If the water enters the boiler at the correct speed
the pressure will drop to approximately 10 p.s.i. then the solenoid
will switch off. The heating and filling cycle will continue until
the top probe and correct pressure are reached.
Technical Specifications :
Size (mm) :
Fast Flow
Height : 474
Width : 345
Depth : 420 (plus 165mm for drip tray)
WB 2 Supreme
Height : 565
Width : 345
Depth : 420 (plus 165mm for drip tray)
Electrical Loading (kw) :
Fast Flow 3 : 3
Fast Flow 6 : 6
Supreme 3 : 3
Supreme 6 : 6
Heat Up From Cold (mins) :
Fast Flow 3 : 36
Fast Flow 6 : 19
Supreme 3 : 51
Supreme 6 : 27
Average Standby Power Consumption (kw/hour) :
Fast Flow 3 : 0.17
Fast Flow 6 : 0.17
Supreme 3 : 0.20
Supreme 6 : 0.20
The Boiler :
The boiler has a design pressure of 2 bar (28 p.s.i.),
is tested to withstand a maximum pressure of 3 bar (42 p.s.i.) and
has a working pressure of 1 bar (14 p.s.i.).
The boiler lid is secured using M6 stainless steel bolts and is
sealed with a non-asbestos gasket and silicone grease.
The boiler should be examined annually for any irregularities by
a qualified person.
Safety Valve :
See Drawing D11
The boiler is fitted with a safety valve with a set blow-off pressure
of 1.6 bar (22 p.s.i.)
This valve is sealed and should not be tampered with. In the case
of leaks it should be replaced. This valves blow-off pressure should
be checked annually by a qualified person.
Anti-Vacuum and Air Release Valve :
See Drawing D11
A vacuum valve is fitted to the boiler.
This has a spindle or a ball which opens when the pressure drops
to zero. This lets air out of the boiler at initial heat up and
air into the boiler when it has cooled down to prevent a vacuum
forming. A vacuum can lead to back syphoning and contamination of
the boiler.
Steam Syphon Pipe :
See Drawing D11
The steam syphon pipe is screwed into the
boiler as a straight pipe and then bend upwards until it is level
with the boiler cover plate. This pipe should never scale up, but
if it needs replacing must be straitened before removal.
Water Syphon Pipe :
See Drawing D11
The water syphon pipe is straight and governs the
amount of water that can be drawn from the boiler. As this pipe
is in contact with the water it can scale up and may need cleaning
or replacing periodically.
The Pressure-stats :
The two pressure-stats on these machines are situated
on a bracket behind the tap bodies. They are factory set and cannot
be adjusted. The pressure-stat on the left, marked M or Mains, with
the orange wires is the operating pressure-stat and is set to 1
bar (14 p.s.i.). The pressure-stat on the right, marked O or Override,
with the purple wires is the override pressure-stat and is set to
1.28 bar (18 p.s.i.). These pressure-stats are not serviceable.
The override pressure-stat only comes into operation if one of the
following happens :-
1 The main pressure-stat fails or loses calibration.
2 The Triac has failed in the closed position.
3 The mains water supply pressure is low or has
been blocked.
4 A wire has shorted.
5 The main pressure-stat capillary tube is blocked.
If this happens it will switch the power to the
machine off via the trip P.C.B. (see page 8).
Machines before 15/5/00 had a high water pressure-stat situated
at the top-rear of the machine. This switched if the incoming water
pressure exceeded 7 bar (100 p.s.i.).
Machines before 10/9/97 had round pressure-stats
situated in the wiring box.
The Heating Element(s) :
The heating elements are made from copper and are
tin plated. They screw into the boiler and are sealed by a non-asbestos
fibre washer and P.T.F.E. tape.
The elements should have a resistance of between 19 and 20 ohms
and will draw between 10 and 11 amps.
If the element has blown it will have an open circuit. To test this
use a simple PAT test.
The Triac :
See Drawing D19
The triac is a device to switch the heating element,
via a control signal (pink wire) from the P.C.B. The triac generates
heat, which has to be dissipated. This is done by bolting it to
the aluminium panel using heat-sink compound between the surface
of the triac and the panel.
There are 2 types of triac’s used on the
Fast Flow and Supreme series. The XE851/L for the 3kw models and
the XE854 for the 6kw models.
If the triac fails, in 90% of cases it will fail in the closed position.
This causes the heating element(s) to remain on. If this happens,
the machine will overheat and the pressure will rise and switch
the override pressure-stat in turn switching the machine off.
If the triac has failed in the closed position there will be continuity
between the live element terminal and the live into the triac (Grey
wire 3kw & red wire 6kw).
To test if the triac has failed (closed circuit),
leave machine plugged in and turn off at the ON/OFF switch (front
panel). If the machine continues to heat when switched off, the
triac is faulty. If not , refer to faultfinding “over-boiling”.
The P.C.B.(s) :
The Trip P.C.B. :
This P.C.B. (FF851) comes into operation when the
override pressure-stat switches. This will switch the power to the
machine off (all lights out). If this happens the machine can only
be re-set by switching the mains power supply to the machine off.
This clears the P.C.B.’s memory.
The Main P.C.B.
This P.C.B. (FF850) controls all the main functions
of the machine, monitoring the water level, pressure, water supply
etc. If a fault is detected the user is warned via the service or
ready L.E.D. Some faults render the machine inoperative whilst others
will only give warning flashes (See chart on page 12 for details).
* Refer to wiring diagram for connections *
The Water Inlet Assembly :
See Drawing D13/N
The water inlet assembly is made up of many different
parts. All pieces are sealed together with NUTLOCK thread sealant.
There are three main components in this line. These are described
below.
Pressure Reduction Valve :
See Drawing D13/N
There are two types of reduction valves used on
this range of machines. These valves must be fitted the correct
way round - See arrow on valve body which shows direction of water
flow.
The self coloured brass valve and the silver valve
can be adjusted by turning the slotted adjustment screw - anti-clockwise
to decrease incoming water pressure.
(Brass valve used March 1996 - February 2000
)
(Silver coloured valve used February 2000 onwards)
The Solenoid Valve :
See Drawing D13/N
Disconnect machine from electrical supply before
replacing. The valve can operate between 2 bar (28 psi) and 7 bar
(100 psi) pressure. The only serviceable part on the valve is the
coil. The coil is susceptible to water damage from steam or water
leaks. This can lead to P.C.B. problems, e.g. blown fuses or electronic
components.
NOTE : Always check solenoid coil before replacing
P.C.B.
Non-Return Valve :
See Drawing D13/N
This valve lets water pass into the boiler, whilst
not letting pressure escape from the boiler. It must be fitted the
correct way round - See arrow on valve body.
The Water Draw Off Tap :
See Drawing D14
The tap washer and/or spring will occasionally
require replacement.
To replace the tap washer. (Part No. TP703)
- switch machine off.
- open steam tap to remove pressure.
- Unscrew bonnet and remove the upper tap assembly
out of the tap body.
- Remove the old washer from the tap spindle and
firmly push the new washer onto the spindle.
- Screw the upper assembly back onto the body.
To replace the tap spring. (Part No. TP702)
- Switch machine off.
- open steam tap to remove pressure.
- Push the pin out of the tap handle.(the pin
has a bend in the middle)
- Unscrew the plastic bonnet to replace broken
spring.(Small diameter down)
- Replace bonnet and handle.
De-scaling - Including cleaning the probes :
- Disconnect the machine from the power supply.
- Remove the lid
- Unscrew M6 bolts and remove boiler lid
- Remove as much loose scale as possible by hand.
- Use a good de-scaler such as “Renegite”
(Part No. ACC303) to remove hard scale deposits. Mix 2-3 packets
in hot water and pour into boiler. Leave for approximately 20
minutes.
- There is a drain plug on the base of the boiler.
- Flush boiler out with water, ensuring that all
traces of de-scaler are removed before
re-assembly.
- To de-scale the level sensing probes, disconnect
probe wires and unscrew using a probe key. Any hard scale coating
on the probes should be cleaned off using a non-metallic scouring
pad. Rinse under cold water and replace.
Fault Finding :
This sections contains a list of faults and causes
that the machine may encounter.
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