Linear Multistream Ceiling Diffuser

Smartemp LMC-AD

High induction linear ceiling slot diffuser with alternating multi-stream mini-jets discharged by nozzle barrels. Nozzle barrel discharge direction is individually adjustable through 90° to alter air pattern from horizontal through diagonal to vertical.

Available with 1-way or 2-way blow patterns. Suitable for low temperature supply air (≥ 5°C) and CAV or VAV systems with extended turndown. Installation flush with ceiling or free-hanging.

Mixed flow discharge:
High induction alternating multi-stream mini-jet discharge from adjustable barrel nozzles located in linear slots intensely mixes supply air with room air. Strong supply air dilution with rapid discharge velocity decay produces draught-free, high momentum supply air motion with uniform temperature distribution over short or long throws. Ideal for enhanced thermal comfort (ADPI ≥ 90%).

Return air:
Also suitable for use as a return air inlet.

Ceiling location:
Integrated flush with a closed ceiling or freely suspended. 1-way blow discharge pattern (adjustable through 90° – horizontal, diagonal, vertical) or 2-way blow discharge pattern (each direction adjustable through 90° – horizontal, diagonal, vertical).

Low temperature supply:
May be used for low temperature (cold air) supply systems (Tsupply ≤ 10 °C), where ∆Tsupply-room ≥ -16 K.

VAV dependent throw:
VAV throw dependent upon airflow rate. Minimum airflow dependent upon ∆Tsupply-room (eg turndown to 25% and ≈1 L/s/m2 @ ∆Tsupply-room ≈ -16 K).

Adjustable direction:
Air pattern adjustment, from horizontal through diagonal to vertical, via individual barrel discharge rotation through 90° Horizontal discharge provides draught-free cooling; vertical discharge provides effective heating.

Manual adjustment:
Airflow direction adjustment is manual. Linear face shape: Aluminium extrusions provide continuous linear aesthetic, with or without side and end flanges.

Slot face pattern:
Barrel nozzles create linear slot appearance.

Plastic Face:
Adjustable black plastic barrel nozzles.

Metal Face:
Anodised or powder coated linear aluminium profiles.

Airflow rate 

  • 6 – 228 L/s/m (22 – 821 m³/h/m)

Nominal length

  • 1200 mm neck
  • 1195 mm face
  • Other lengths and joining strips available on request
  • Available with or without side/end flanges

Element width

  • Flangeless: n x 28 + 3 mm, where n = number of rows (1 to 6 rows)
  • Flanged: n x 28 + 20 mm, where n = number of rows (1 to 6 rows)

Discharge height

  • 2.4 – 4.5 m


  • 1 – 6 slot configurations
  • 1 or 2 way discharge patterns
  • Adjustable horizontal, diagonal or vertical discharge direction
  • High induction alternating mini-jet discharge
  • Barrel nozzles individually adjustable through 90°
  • Barrel nozzles of plastic, black
  • Side and end profiles of aluminium, natural anodised or powder coated
  • Flanged or flangeless side and end profiles
  • Installation flush with ceiling or free hanging


The SMARTEMP Linear Multistream Ceiling Diffuser, type LMC-AD, is a high induction linear slot diffuser. A multitude of barrel nozzles produce alternating mini-jet discharge. The discharge direction of each barrel nozzle is individually adjustable, providing accurate air pattern adjustment. The diffuser is available with 1-way (adjustable through 90° for horizontal through diagonal to vertical discharge) or 2-way discharge patterns (each direction adjustable through 90° for horizontal through diagonal to vertical discharge).

The diffuser may be flush mounted in a ceiling or freely suspended (ie no Coanda attachment to the ceiling required). The diffuser’s 1 to 6-row linear slots (greater slot numbers available on request) comprise a multitude of nozzles with manually adjustable discharge direction adjustment to produce high induction discharge by breaking up the supply air stream into many miniature jets.  The barrel nozzles are made of polycarbonate, dyed black, and are located in aluminium extrusions that are anodised or powder coated.

High induction discharge offers many advantages. High aspiration causes intense mixing at the diffuser discharge face, strongly diluting the supply air stream with large quantities of room air. High induction, additionally, rapidly equalises the supply air stream temperature with room air, preventing cold air dumping. Rapid supply-to-room air temperature equalisation also improves heating performance by preventing the supply air from being too bouyant. High induction airflow is characterised by uniform temperature distribution and high comfort levels in the space. High induction also produces a strong increase in supply air stream mass flow rate, as well as rapid discharge velocity decay. At any given airflow rate, the SMARTEMP LMC-AD diffuser is suitable both for long throws (due to the supply air stream’s high momentum) as well as short throws (due to the supply air stream’s low velocity).

The SMARTEMP LMC-AD diffuser may be used in CAV systems, as well as VAV systems, including low-temperature supply air systems with ΔTsupply-room ≥ -16 K. VAV system turndown is dependent upon ΔTsupply-room (eg to 25% at ΔTsupply-room = -16 K). Due to high induction mini-jet discharge, the effective air changes per hour in the space are increased, allowing minimum specific airflow rates as low as approximately 1 L/s/m2 when the diffuser is fully turned down, whilst maintaining enhanced comfort of 90% ADPI. Due to the rapid discharge decay characteristics of the micro-jet discharge, a high maximum specific airflow rate of 15 L/s/m2 may be achieved at 90% ADPI.

Side-entry connection boxes with concealed diffuser fastenings.

Product Type



Airflow Direction

Face Material


Face Pattern

Face Shape


Supply Temperature



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