Rickard VSW 150 User manual

WBD WITH DEDICATED HEATER FITTED
FEATURES
FORM FACTOR
RICKARD diffusers are fitted with electric re-heaters that are either
housed in a modular sleeve (VCD1, VSD1, CCD3, CSD3, VSW1 &
CSW3’s) or fitted directly to the unit (WBD, VLN). The heaters are
energised when additional heating is required in a room.
Electric heating can be considered to save energy when they are
used to heat isolated offices that wouldn’t be efficiently heated by
raising the central plants temperature. The most efficient scenario in
heating is for the central plant to supply sufficient heated air to allow
most of the zones to be in control when the diffusers damper is
close to minimum position. Zones that are colder are controlled by
the diffuser opening further. Zones that cannot be satisfied by the
diffuser supplying warm air at full volume are toped up with supple-
mentary heating.
The most efficient scenario in cooling is for the central plant to sup-
ply sufficient cool air to allow most of the zones to be in control
when the diffuser dampers are close to minimum position. Zones
that are warmer can be controlled by the diffuser opening further.
Zones that cannot be warmed sufficiently by reducing the cold air
supply can be controlled by heating this reduced volume of air.
If the room temperature were to fall by 0.5°C below set point, the
Triac Controller will commence energizing the heater proportionally
and will fully energize the heater when the room temperature is ap-
proximately 1.5°C below set point.
To ensure a building is efficiently heated it is necessary to integrate
the Rickard VAV diffuser system with the central plant BMS. This is
possible by using Rickard’s MLM BMS Compatible Controls.
PROPORTIONAL HEATING
For accurate control of room temperature, the electric re-heater is
controlled on a step-less, proportional basis. In addition to having a
proportional output signal for cooling control, the temperature con-
troller also has a proportional output signal for heating.
This is done by means of a triac switching set (current valve) which
varies the heater output capacity by cycling the power supply to the
heater on and off –Pulse Width Modulation (PWM). This switching
takes place over a cycle of approximately 2 seconds and always oc-
curs at zero voltage to avoid radio frequency interference and volt-
age spikes. The “on” and “off” periods are varied in proportion to
the amount of heating required, i.e. a required heating capacity of
75% will result in an “on” period of 1.5 seconds and an “off” period
of 0.5 seconds.
CONTROLS
In a situation where multiple diffusers are controlled from a single
controller, each diffuser will be fitted with its own triac that will re-
ceive a heating signal from the Primary controller. From the table
“Maximum Recommended Heater Output (Watts)” at the end of this
section, notice that for each neck total pressure there is a specific
heater output quoted. For each diffuser size a standard heater capac-
ity is referenced e.g. in the case of a VCD 250 diffuser, the re-heater
sleeve would be factory fitted with a 1500 watt heater. By utilizing
the RICKARD MLM or MLM Interoperable BMS Compatible Controls,
the heater can be electronically set for an output from 100 to 1500W
to match the design engineer’s requirements. If the diffuser neck
total pressure were to be set to 50Pa and the minimum desired air
flow was 30% of maximum with a 17°C temperature rise, the heater
output for a VCD 250 should be set to 1350 watts. Please refer to
the MLM software help section for setup information.
IMPORTANT ELECTRICAL INFORMATION: Electrical reticulation
should be designed to manage the heaters full capacity i.e. when a
heater is set to 50%, the heater element draws the same current as it
would when set to 100% but only draws it for 50% of the time.
VAV PLATE DIFFUSER FITTED WITH MODULAR HEATER SPIGOT

SELECTION GUIDELINES
When calculating heater capacities for VAV diffusers, please keep in
mind that heating in the cooling mode takes place when the
diffuser is supplying minimum air flow. Care must therefore be
taken to ensure that excessive supply air temperature rises are
avoided. Discharge temperatures in excess of 32°C are likely to
cause stratification within the room. As a guide-line, the
temperature of the air leaving the diffuser should not be more than
10°C above room temperature. Please refer to the “Maximum
Recommended Heater Output (Watts)” table on page 3 for each
diffuser size. These heater output ratings calculated to ensure that
the heat rise is no more than 15°C in VAV diffusers and 10°C in CAV
diffusers. Please note that these values are a guide and are
calculated at 30% volume for VAV diffusers and 100% volume for
CAV diffusers.
IMPORTANT: These maximum capacities do not take into account
limitations of the triac which are rated at 12A maximum. This
reduces the capacity of the triac at low voltage supply.
ELECTRICAL AND OVERHEAT SAFETIES
NOTE: The following safeties should not exclude ducting airflow
safeties and a dedicated heater electrical circuit. Please see the
following Installation guidelines section.
Every Heater Module is fitted with a coiled electrical element inside
a Galvanised sheet metal enclosure. The heater elements is
constructed from an Incaloy material that does not glow when
energised. This element is selected to reduce the risk of combustible
materials igniting should they come into contact with the heater
element itself. No combustible materials are used in the
construction of a Rickard Diffuser or Heater Module. Rickard
diffusers use a high spec flame retardant, self extinguishing
polycarbonate plastic that is chlorine and bromine free with a UL94
V-0 rating at 1.5mm. The Heater modules are fitted with their own
Triac/Heater driver and receive a proportional signal from the
diffuser controls when heating is required. The Triac receives its
power from a separate power circuit. Dedicated plug tops can be
fitted to the heater module on request.
Each heater modules is fitted with a number of safeties to reduce
the risk of failure. The Triac is fitted inside an electrically grounded
metal enclosure that is physically attached to the heater module
enclosure. This increases the electrical safety of the device should a
short circuit occur. A fuse offers additional protection against large
current surges and shorts. A Transient suppressor prevents the Triac
from failing closed and therefore driving the heater permanently if a
voltage surge has occurred.
In some cases when no flow or very low flows occur in the ducting,
it is necessary to limit the heaters output to avoid excessive heat
build up in the diffuser. For this reason the triac is fitted with a
temperature sensor and controls to limit the triac so that the supply
air exiting the diffuser never rises above 50°C or 122°F.
As an added safety an auto-reset 65°±5°C or 149±9°F(10 000 cycles)
safety cut-out is fitted as standard. The reset temperatures indicates
the air temperature inside the overheat safety cut-out casing at
which it operates. Rickard heater modules are designed so that the
overheat safety cut-outs trigger when the neck Total pressure is
approximately 30Pa or below. The trigger point can vary depending
on a number of factors namely, excessively squashed or bent flex,
neck size, heater size and damper position. Rickard controls do not
activate its heaters below 20% flow damper position, thereby
reducing the likelihood of the overheat safeties not triggering in the
range described. Push-button type manual reset safeties are not
recommended in conjunction with diffuser re-heaters.
For additional safety, RICKARD offer an Airflow Switch to interrupt
power to the re-heater controls when there is insufficient airflow
across the heater element. The switch is calibrated to disable the
heater current valve below a static pressure of 12Pa (+/- 5Pa).
The switch operates as a dead man switch i.e. if the cable between
the switch and the heater controls is unplugged, the heater will not
operate.
TESTING
All electrical wiring associated with the re-heater is carried out in
the factory and all units are carefully tested for correct operation.
OPTIONS
• Heaters are available in various capacities, ranging from
0.5kW to 2.5kW.
• Airflow Switch to interrupt power to the re-heater controls
when there is insufficient airflow across the heater element.
STANDARD SAFETIES FITTED TO ALL VAV DIFFUSER TYPE
(VCD1, VSD1, CCD3, CSD3, VSW1, CSW, WBD’s , CLN’s and VLN’s )
Air flow Switch
Triac/current valve
Auto-reset Cut-out
OPTIONAL AIRFLOW CUT-OUT/SWITCH
Safety Temperature Sensor

INSTALLATION GUIDELINES
Your duct design should supply between 30 and 60Pa total pressure at each diffuser to ensure adequate flow across the heaters.
Please ensure the ducting is fitted with an airflow interlock/paddle switch that cuts the power to the electrical reticulation serving the
diffusers in the event of a loss of flow. This will ensure that the diffusers heaters are not energised when the AHU is off.
Rickard recommends a dedicated electrical outlet be fitted to the building heater reticulation and dedicated plug top be fitted to the
diffusers . This will ensure that the airflow interlock always cuts power to the diffusers heaters and not other equipment plugged into the
same circuit. This will also ensure that heaters are always plugged into a protected circuit.
Please see the “Electric Plug Ordering” Document for more details to order the correct plug top for your installation.
VCD
Recommended Heater sengs & sizing for a 15 Degree C Heat Rise @ 30% Open
Pa 20 30 40 50 60 70
Neck
Size
kW kW kW kW kW kW
Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set
150 0.35 0.50 70% 0.34 0.50 68% 0.50 0.50 100% 0.50 0.50 100% 0.60 0.75 80% 0.65 0.75 87%
200 0.60 0.75 80% 0.70 0,75 93% 0.75 0.75 100% 0.90 1.00 90% 1.00 1.00 100% 1.00 1.00 100%
250 0.85 1.00 85% 1.00 1.00 100% 1.15 1.25 92% 1.30 1.50 87% 1.40 1.50 93% 1.50 1.50 100%
300 1.00 1.00 100% 1.25 1.25 100% 1.50 1.50 100% 1.65 2.00 83% 1.75 2.00 88% 2.00 2.00 100%
350 1.30 1.50 87% 1.50 1.50 100% 1.85 2.00 93% 1.85 2.00 93% 2.25 2.50 90% 2.50 2.50 100%
VSW
Recommended Heater sengs & sizing for a 15 Degree C Heat Rise @ 30% Open
Pa 30 40 50 60 70
Neck
Size
kW kW kW kW kW
Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set
150 0,35 0,5 70% 0,4 0,5 80% 0,45 0,5 90% 0,5 0,5 100% 0,55 0,75 73%
200 0,6 0,75 80% 0,7 0,75 93% 0,8 180% 0,85 185% 0,9 190%
250 0,85 185% 11,25 80% 1,1 1,5 73% 1,2 1,25 96% 1,3 1,5 87%
300 11100% 1,2 1,5 80% 1,35 1,5 90% 1,5 1,5 100% 1,6 280%
VLN1
2 Slot
Paern
C
Recommended Heater sengs & sizing for a 15 Degree C Heat Rise @ 30% Open
Pa 30 40 50 60 70
Length kW kW kW kW kW
Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set
600 0,3 0,5 60% 0,35 0,5 70% 0,35 0,5 70% 0,4 0,5 80% 0,45 0,5 90%
900 0,45 0,5 90% 0,55 0,55 100% 0,6 0,75 80% 0,65 0,75 87% 0,7 0,75 93%
1200 0,65 0,75 87% 0,75 0,75 100% 0,8 180% 0,9 0,9 100% 11100%
1500 0,85 0,85 100% 11100% 1,1 1,25 88% 1,2 1,2 100% 1,3 1,5 87%
WBD
Recommended Heater sengs & sizing for a 15 Degree C Heat Rise @ 30% Open
Pa 20 30 40 50
Size (mm) kW kW kW kW
Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set
300/100 0,4 0,5 80% 0,5 0,5 100% 0,55 0,75 73% 0,6 0,75 80%
350/100 0,55 0,75 73% 0,65 0,75 87% 0,7 0,75 93% 0,75 0,75 100%
400/100 0,6 0,75 80% 0,75 0,75 100% 0,8 180% 0,9 190%
450/100 0,7 0,75 93% 0,8 180% 0,9 190% 11100%
500/100 0,7 0,75 93% 0,85 185% 0,95 195% 1,1 1,25 88%
550/100 0,75 0,75 100% 0,95 195% 1,1 1,25 88% 1,2 1,25 96%
600/100 0,9 190% 11100% 1,2 1,25 96% 1,25 1,25 100%
650/100 0,95 195% 1,15 1,25 92% 1,25 1,25 100% 1,45 1,5 97%
500/150 11100% 1,25 1,25 100% 1,6 280% 1,8 290%
550/150 1,2 1,25 96% 1,4 1,5 93% 1,65 283% 1,85 293%
600/150 1,4 1,5 93% 1,6 280% 1,9 295% 22100%
650/150 1,4 1,5 93% 1,7 285% 22100% 2,2 2,5 88%
700/150 1,5 1,5 100% 1,85 293% 2,2 2,5 88% 2,4 2,5 96%
800/150 1,75 288% 2,1 2,5 84% 2,5 2,5 100% 2,5 2,5 100%
To limit stratification in heating Rickard recommends that the heater outputs be limited to the values published in the tables above. The calculated values will
ensure that the heat rise is no more than 15°C in VAV diffusers and 10°C in CAV diffusers. Please note that these values are a guide and are calculated at 30%
volume for VAV diffusers and 100% volume for CAV diffusers. By adjusting the diffuser damper position down, a smaller volume will create a larger heat rise and
therefore increase the likelihood of stratification. The Fit column indicates the maximum fitted heater size recommended, the Adjust value indicates the maxi-
mum heater setting recommended to achieve a 15°C (VAV) or 10°C (CAV) heat rise and the Set column is the MLM Heater Output % value required to achieve a
15°C (VAV) or 10°C (CAV) heat rise.

To limit stratification in heating Rickard recommends that the heater outputs be limited to the values published in the tables above. The calculated values will
ensure that the heat rise is no more than 15°C in VAV diffusers and 10°C in CAV diffusers. Please note that these values are a guide and are calculated at 30%
volume for VAV diffusers and 100% volume for CAV diffusers. By adjusting the diffuser damper position down, a smaller volume will create a larger heat rise and
therefore increase the likelihood of stratification. The Fit column indicates the maximum fitted heater size recommended, the Adjust value indicates the maxi-
mum heater setting recommended to achieve a 15°C (VAV) or 10°C (CAV) heat rise and the Set column is the MLM Heater Output % value required to achieve a
15°C (VAV) or 10°C (CAV) heat rise.
CCD
Recommended Heater sengs & sizing for a 10 Degree C Heat Rise @ 100% Open
Pa 20 30 40 50 60 70
Neck Size
(mm)
kW kW kW kW kW kW
Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set
150 1.30 1.50 87% 1.50 1.50 60% 1.75 2.00 88% 2.00 2.00 100% 2.25 2.50 90% 2.40 2.50 96%
200 1.80 2.00 90% 2.25 2.50 90% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100%
250 2.30 2.50 92% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100%
300 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100%
350 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 200%
Max Element Size before extending spigot length: 150mm = 0.75kW, 200mm = 1.25kW, 250mm = 1.5kW, 300mm = 2.0kW, 350mm = 2.5kW
CSW
Recommended Heater sengs & sizing for a 10 Degree C Heat Rise @ 100% Open
Pa 20 30 40 50 60 70
Neck Size
(mm)
kW kW kW kW kW kW
Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set Adjust Fit Set
150 0.70 0.75 93% 0.80 1.00 80% 1.00 1.00 100% 1.00 1.00 100% 1.15 1.25 92% 1.25 1.25 100%
200 1.20 1.25 96% 1.30 1.50 87% 1.50 1.50 100% 1.75 2.00 88% 1.90 2.00 95% 2.00 2.00 100%
250 1.80 2.00 90% 2.00 2.00 100% 2.25 2.50 90% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100%
300 2.00 2.00 100% 2.40 2.50 96% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100% 2.50 2.50 100%