Kaden KE3, Installer Manual

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Good duct design and sizing are essential to every Kaden Central Heating system. Use the Kaden Size Guide and
technical data within this manual for the best results and follow these guidelines:
•
Ductwork should be well insulated and airtight and have a minimum insulation rating of R1.0 (R1.5 in some
areas). Ensure that ducting complies with the Building Code of Australia.
•
The ducting should be well fastened to pops, BTO’s, outlet boots and neck adapters adequately with duct tape,
in accordance with AS 4254 and HB 276.
•
It should also be properly sized, and curves and bends should be smooth enough to ensure that the air flows
through efficiently, quietly and with minimal resistance.
•
The registers and diffusers should be large enough and of good design. They should minimise noise, while
providing the correct distribution pattern.
•
The positive return air system should be fitted with a grille large enough to accept the full air capacity of the
system at low noise levels.
•
If the system uses high level outlets (e.g. ceiling diffusers), then the return air inlet should be at a low level.
Ceiling systems with a high level return air may result in reduced performance.
•
For all Kaden heaters, access to the ductwork must be provided for general maintenance and service to the
supply air thermistor sensor where applicable.
NOTE
It is important that the ducting should be well insulated. It is mandatory under building codes to
install insulated, fire rated duct.
If a filter is fitted to the return air grille, it should be easily accessible for regular cleaning. Table 5 gives the minimum
recommended return air grille sizes for each model heater to handle the maximum rated airflow.
6.1 MINIMUM RECOMMENDED RETURN AIR GRILLE SELECTION CHART
Model
Without Filter With Filter
Grille Size (m²) Example of Size (mm) Grille Size (m²) Example of Size (mm)
KU521 0.28 400 x 700 0.42 400 x 1050
KU530 0.36 400 x 900 0.54 400 x 1350
KU415 0.26 400 x 650 0.39 400 x 1000
KU420 0.26 400 x 650 0.39 400 x 1000
KU425 0.26 400 x 650 0.39 400 x 1000
KU430 0.31 400 x 800 0.47 400 x 1200
KU315 0.19 400 x 475 0.28 400 x 700
KU320 0.22 400 x 550 0.32 400 x 800
KU325 0.24 400 x 600 0.35 400 x 875
KU330 0.35 400 x 1000 0.51 400 x 1275
KE415 0.19 400 x 475 0.28 400 x 700
KE420 0.22 400 x 550 0.32 400 x 800
KE420XA* 0.24 400 x 600 0.35 400 x 875
KE428 0.32 400 x 800 0.46 400 x 1150
KE428XA* 0.35 400 x 875 0.54 400 x 1350
KE315 0.19 400 x 475 0.51 400 x 700
KE320 0.22 400 x 550 0.32 400 x 800
KE320XA* 0.24 400 x 600 0.35 400 x 875
KE328 0.32 400 x 800 0.46 400 x 1350
KE328XA* 0.35 400 x 875 0.51 400 x 1275
* XA is based on base box POP sizes.
Table 5
NOTE
Grille sizes are based on maximum airflow with typical Egg-Crate Grille type. For all other types,
consult grille manufacturer’s specifications. For example a grille with a free ventilation opening
measuring 400mm x 750mm, the grille size is 0.4m x 0.75m = 0.3m2. This grille would be suitable
for a KU521 heater provided the grille does not have a filter fitted.
6. DUCTING INFORMATION