Ventilation and Air Conditioning
Supply, extract and air conditioning, drawn as ducts between fans, units, grilles and diffusers. 33 fittings, round and rectangular ducts, and the air through each duct read from the terminals it serves.
Every property, and what it does
Select a duct or a fitting and these are its rows. A band shows when it applies, so a rectangular duct has its aspect and equivalent round size.
The catalogue
The fittings, by the system they are on.
| Field | What it does | Values |
|---|---|---|
| Supply air | The supply air fittings, each with its plan symbol and its usual mounting height. | Transfer grille, External louvre, Balancing damper, Volume control damper, Fire damper, Fire and smoke damper, Smoke damper, Relief damper, Humidity sensor, MVHR unit, Inline fan, Centrifugal fan, Duct silencer, Air filter |
| Extract air | The extract air fittings, each with its plan symbol and its usual mounting height. | Extract fan, Backdraft damper |
| Air conditioning | The air conditioning fittings, each with its plan symbol and its usual mounting height. | Supply diffuser, Return grille, Air handler, Supply register, Cooled beam, VAV box, CAV box, Split system, Air conditioning unit, Rooftop unit, Dehumidifier, Chiller, Cooling coil, Humidifier |
| Refrigeration | The refrigeration fittings, each with its plan symbol and its usual mounting height. | Compressor, Condenser, Evaporator |
Element
What the selected run or fitting is, and which trade it belongs to.
| Field | What it does | Values |
|---|---|---|
| What it is | The catalogue name of the fitting, or the kind of run. | Read from the element |
| Kind | The catalogue entry it was drawn from. Change it to swap the fitting, keeping where it sits. | The 33 fittings of the trade |
| System | What it carries. It decides which trade owns it, its colour and its schedule. | Supply air, Extract air, Air conditioning, Refrigeration |
| Trade | The trade that owns it, read from the system. To move it, change the system. | Read from the system |
| Supply | Whether a fitting that needs a supply is connected to one by a run. | Connected, Not connected, Not required |
Design
Grilles, diffusers and units are drawn from their own design, so the symbol and the body follow it.
| Field | What it does | Values |
|---|---|---|
| Preset | A named design for the fitting. Change anything in it and it reads as modified. | The fitting's named designs |
| Design controls | The parts of the fitting itself, drawn from its own generator, so its symbol and its 3D body follow. | By fitting |
| What that makes it | What the design comes to, read only, so the schedule cannot disagree with the fitting. | Face, Opening, Free area, Face velocity, Limit, Neck |
Air
The air through a duct and how fast it runs.
| Field | What it does | Values |
|---|---|---|
| Equivalent round | On a rectangular duct, the round size with the same friction. | Millimetres, read only |
| Aspect | The long side over the short. Flatter than 4 to 1 is flagged. | Read only |
| Air behind it | The air the terminals this duct reaches ask for, from the plant out. | Litres per second, read only |
| Air through it | The air you type for the duct. | Litres per second |
| Speed, Limit | How fast the air runs, against the limit for a duct in that role, so it does not run noisy. | Metres per second, read only |
Size
The size of a run, and how the plan draws it.
| Field | What it does | Values |
|---|---|---|
| Nominal | The diameter of a round run, or the larger side of a duct. | Duct sizes in mm, round or width by height |
| Shape | Round, or rectangular with a width and a height. | Round, Rectangular |
| Drawn as | Runs 75 mm and over are drawn to their width with two lines; smaller ones as a single line. | Single line, Double line to width |
Where it runs, where it sits
A run has two ends and a level at each; a fitting has a height and a facing.
| Field | What it does | Values |
|---|---|---|
| Start, End | The fitting each end is bound to. A bound end goes wherever the fitting goes. | Read from the plan |
| Level at start, Level at end | How high each end is above the storey's floor. | Millimetres |
| Invert at start, Invert at end | The level of the inside bottom of the pipe at each end, for runs that fall. | Derived from the run it leaves and its gradient |
| Length in plan | The run's length on the plan. | Read from the plan |
| Drop | How far the run falls from start to end. | Derived from the two levels |
| Height | How high a fitting stands above the storey's floor. Negative is below ground. | Millimetres; each fitting starts at its usual height |
| Facing | Which way a fitting faces, anticlockwise from east. 90 faces up the page. | Degrees |
| Flip to the other side | Moves a wall fitting onto the other face of its wall, pointing into the other room. | One click |
Belongs to
What the schedule files it under, and whether a person has checked it.
| Field | What it does | Values |
|---|---|---|
| Circuit | The circuit or zone the schedule files it under. Where a fitting is wired, the wiring decides. | Any name |
| Proposed | Marks what a generator wrote and nobody has checked yet. Confirm clears it. | Confirm |
How the Ventilation tools work
Open Ventilation
In the editor, open CAD tools and choose Ventilation. The group has three tools: Catalogue (VENTILATION), Duct (DUCT) and Place (PLACEAIR).
Place the fittings
Pick a fitting from the catalogue by its system and click where it goes. It stands at its usual height, which its panel can change.
Draw the ducts
With Duct (DUCT), click each point and press Enter. A run that starts or ends on a fitting snaps to its connection point and is joined to it.
Shape the ducts
Select a duct to make it rectangular and give its width and height. Its panel shows the air through it and its speed.
Ventilation questions, answered.
What can I place?
MVHR units, inline and centrifugal fans, extract fans, grilles, louvres and diffusers, dampers of every kind, filters and silencers, split systems, air handlers, rooftop units, VAV and CAV boxes, chillers and coils.
Can I draw rectangular ducts?
Yes. Set a duct's shape to rectangular in its panel and give its width and height. It shows the equivalent round size too.
Does it check the ducts?
Yes, as advice: a rectangular duct flatter than 4 to 1, and a duct too small for its air, so the air runs too fast.
Are the services in 3D too?
Yes. Runs are built as real cables, pipes and ducts at their levels, fittings stand at their heights, and a run that crosses a wall or a floor cuts its own hole through it.
Read on
- Plumbing and Heating: Water, heating and gas pipes.
- Electrical: Sockets, switches, lights and circuits.
- Ventilation docs: Ducts, air and the checks.