Application
Special characteristics
Nominal sizes
Variants
Heat exchanger
Nozzle variants
Construction
Attachments
Accessories
Useful additions
Construction features
Materials and surfaces
Standards and guidelines
Maintenance
Functional description
Induction-type displacement flow diffusers provide centrally conditioned primary air (fresh air) to the room and use heat exchangers for cooling and/or heating.
The primary air is discharged through nozzles and induces secondary air (room air), which passes through the heat exchanger.
Primary and secondary air mix and are then supplied to the room, causing only very little turbulence.
Nominal length | 900, 1200, 1500 mm |
Length | 975, 1275, 1575 mm |
Height | 729 mm |
Width | 195 mm |
Primary air volume flow rate | 4 – 50 l/s or 14 – 180 m³/h |
Cooling capacity | Up to 1000 W |
Heating capacity | Up to 750 W |
Max. operating pressure, water side | 6 bar |
Max. operating temperature, water side | 75 °C |
The quick sizing table contains operating points for defined reference units. For other operating points you may use the Easy Product Finder design software.
Quick sizing
900 | M | 4 | 14 | 53 | <20 | 237 | 188 | 1.5 | 3.1 | 228 | 3.9 | 0.2 |
900 | M | 6 | 22 | 121 | 24 | 332 | 260 | 2.0 | 3.1 | 314 | 5.4 | 0.2 |
900 | M | 8 | 29 | 217 | 32 | 415 | 318 | 2.5 | 3.1 | 386 | 6.6 | 0.2 |
900 | G | 7 | 25 | 40 | <20 | 317 | 233 | 1.8 | 3.1 | 281 | 4.8 | 0.2 |
900 | G | 11 | 40 | 102 | 22 | 456 | 323 | 2.5 | 3.1 | 392 | 6.7 | 0.2 |
900 | G | 15 | 54 | 191 | 31 | 571 | 391 | 3.1 | 3.1 | 474 | 8.2 | 0.2 |
900 | U | 17 | 43 | 42 | <20 | 387 | 242 | 1.9 | 3.1 | 293 | 5.0 | 0.2 |
900 | U | 19 | 68 | 108 | 28 | 550 | 321 | 2.5 | 3.1 | 389 | 6.7 | 0.2 |
900 | U | 26 | 94 | 204 | 37 | 677 | 364 | 2.8 | 3.1 | 441 | 7.6 | 0.2 |
1200 | M | 5 | 18 | 45 | <20 | 293 | 233 | 1.8 | 3.8 | 281 | 4.8 | 0.3 |
1200 | M | 8 | 29 | 117 | 23 | 431 | 335 | 2.6 | 3.8 | 406 | 7.0 | 0.3 |
1200 | M | 11 | 40 | 222 | 32 | 548 | 416 | 3.3 | 3.8 | 505 | 8.7 | 0.3 |
1200 | G | 9 | 32 | 37 | <20 | 401 | 293 | 2.3 | 3.8 | 355 | 6.1 | 0.3 |
1200 | G | 15 | 54 | 106 | 23 | 601 | 420 | 3.3 | 3.8 | 510 | 8.8 | 0.3 |
1200 | G | 21 | 46 | 208 | 33 | 761 | 508 | 4.0 | 3.8 | 618 | 10.6 | 0.3 |
1200 | U | 16 | 58 | 45 | <20 | 506 | 313 | 2.4 | 3.8 | 379 | 6.5 | 0.3 |
1200 | U | 25 | 90 | 112 | 31 | 709 | 408 | 3.2 | 3.8 | 495 | 8.5 | 0.3 |
1200 | U | 34 | 122 | 207 | 40 | 871 | 461 | 3.6 | 3.8 | 560 | 9.6 | 0.3 |
1500 | M | 6 | 22 | 41 | <20 | 347 | 275 | 2.2 | 4.5 | 333 | 5.7 | 0.4 |
1500 | M | 10 | 36 | 115 | 23 | 526 | 405 | 3.2 | 4.5 | 492 | 8.5 | 0.4 |
1500 | M | 14 | 50 | 228 | 33 | 674 | 505 | 3.9 | 4.5 | 614 | 10.6 | 0.4 |
1500 | G | 11 | 40 | 36 | <20 | 483 | 350 | 2.7 | 4.5 | 424 | 7.3 | 0.4 |
1500 | G | 19 | 68 | 111 | 25 | 737 | 508 | 4.0 | 4.5 | 618 | 10.6 | 0.4 |
1500 | G | 27 | 97 | 225 | 35 | 939 | 613 | 4.8 | 4.5 | 747 | 12.9 | 0.4 |
1500 | U | 20 | 72 | 49 | 23 | 621 | 380 | 3.0 | 4.5 | 461 | 7.9 | 0.4 |
1500 | U | 28 | 101 | 98 | 33 | 802 | 464 | 3.6 | 4.5 | 564 | 9.7 | 0.4 |
1500 | U | 36 | 130 | 163 | 41 | 956 | 521 | 4.1 | 4.5 | 634 | 10.9 | 0.4 |
① Nozzle variant ② Air-regenerated noise
Reference values
tR | 16 °C | 22 °C |
tPr | 16 °C | 50 °C |
tWV | 26 °C | 22 °C |
VW | 110 l/h | 50 l/h |
Induction-type displacement flow diffuser of Type QLI, with one-way discharge and high thermal output, providing high thermal comfort levels.
For installation on a wall or under the sill
The units consist of a casing with a primary air plenum, spigot, non-combustible nozzles, and vertical heat exchanger; a condensate drip tray is optional.
Special characteristics
Materials and surfaces
Construction
Technical data
This specification text describes the general properties of the product. Texts for variants can be generated with our Easy Product Finder design programme.
QLI–2–G–WVL/1200
Heat exchanger | 2-pipe |
Nozzle variant | Medium |
Arrangement of heat exchanger and water connections | Ø12 mm pipe, plain tails |
Nominal length | 1200 mm |
QLI–4–U–WHR–KW/1200/WB/P1/VS
Heat exchanger | 4-pipe |
Nozzle variant | Extra large |
Arrangement of heat exchanger and water connections | At the rear, water connections on the right |
Condensate drip tray | With |
Nominal length | 1200 mm |
Fixing | Wall and floor fixing |
Surface | Powder-coated black |
Valves and actuators | With |
Installation and commissioning
LN [mm]
Nominal length
LWA [dB(A)]
Sound power level
tPr [°C]
Primary air temperature
tWV [C°]
Water flow temperature – cooling/heating
tR [C°]
Room temperature
tR [C°]
Room temperature
tAN [C°]
Secondary air intake temperature
QPr [W]
Thermal output – primary air
Qtot [W]
Thermal output – total
QW [W]
Thermal output – water side, cooling/heating
VPr [l/s]
Primary air volume flow rate
VPr [m³/h]
Primary air volume flow rate
VW [l/h]
Water flow rate – cooling/heating
V [l/h]
Volume flow rate
∆tW [K]
Temperature difference – water
∆pW [kPa]
Pressure drop, water side
∆pt [Pa]
Total pressure drop, air side
∆tPr = tPr - tR [K]
Difference between primary air temperature and room temperature
∆tRWV = tWV - tR [K]
Difference between water flow temperature and room temperature
∆tWm-Ref [K]
Difference between mean water temperature and reference temperature
LN [mm]
Nominal length
Displacement flow ventilation
The supply air is discharged into the space with a velocity between 0.15 and 0.20 m/s and as close as possible to the floor; the result is a pool of fresh air over the entire floor area. The convection from people and other heat sources causes the fresh air from the pool to rise and create comfortable conditions in the occupied zone. Displacement ventilation is characterised by low airflow velocities and low turbulence. The air quality in the occupied zone is very high. The extract air should ideally be removed near the ceiling.
Heat exchanger
The maximum water-side operating pressure for all heat exchangers is 6 bar.
The maximum water flow temperature (heating circuit) for all heat exchangers is 75 °C; if flexible hoses are used, the water flow temperature should not exceed 55 °C. Units for other pressures and temperatures are available on request.
The water flow temperature (cooling circuit) should be at least 16 °C such that it does not permanently fall below the dew point. For units with a condensate drip tray the water flow temperature may be reduced to 15 °C.
Heat exchanger as 2-pipe system
Air-water systems with a 2-pipe heat exchanger may be used for either heating or cooling. In changeover mode it is possible to use all units within a water circuit exclusively for cooling in summer and exclusively for heating in winter.
Heat exchanger as 4-pipe system
Air-water systems with a 4-pipe heat exchanger may be used for both heating and cooling. Depending on the season, i.e. especially in spring and autumn, it may be possible that an office has to be heated in the morning and cooled in the afternoon.
Type QLI
Induction-type displacement flow diffuser in nominal lengths of 900, 1200 and 1500 mm, with vertical heat exchanger and condensate drip tray
Induction-type displacement flow diffuser with 2-pipe or 4-pipe heat exchanger, for installation under a sill. The condensate drip tray is useful if the temperature temporarily falls below the dew point.
Optional equipment and accessories
For further product information please click here
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Contact
We are here for you
Please specify your message and type of request.
Tel.: +44 (0)1842 754545 | Fax: +44 (0)1842 763051
Contact
Thank you for your message!
Your message is send and will be processed shortly.
Our department for Service-Requests will contact you asap.
For general question regarding products or services you can also call:
Tel.: +44 (0)1842 754545 | Fax: +44 (0)1842 763051