Multi-Apartment Air Conditioning

AIR CONDITIONING SYSTEMS – QUICK CHOICE

Typical Systems:

  • Single Apartment Systems – Small (1 to 1 SPLIT)
  • Single Apartment Systems – Small (1 to 1 MULTI)
  • Single Apartment Systems – Medium VRF/VRV (1 to 1 SPLIT)
  • Multi Apartment Systems – Large VRF/VRV (Heat Recovery) (1 to MULTI)
  • Centralised Systems – Water Cooled
  • Centralised Systems – Chilled Water
  • Centralised Systems – Hybrid (Common/Central system to serve multiple apartments)

 

Systems Considerations:

The following is considered when deciding on which AC system.

Consideration 1:

  • Power and Maintenance by apartment occupier

Aim: Apartment Owner: Responsible for all power consumption and maintenance of the AC system. 

With this driver, air conditioning can be provided from:

  • splits and medium to large sized splits with VRF/VRV units.

[See AC types; 1a, 1b, 1c, 1d, 1e, 1f and 2a, 2b, 2c, 2d and 3a & 3b].

Other systems are common AC systems where billing and maintenance are shared.

Consideration 2:

  • Balcony Located Units not allowed,
  • Building 15 to 28 levels (<90m),
  • No condensers on roof,
  • Power and Maintenance by apartment occupier

So, you cant have balcony located units, and the building height precludes AC units on the roof (could also be needed for tenant activation) then….

With this driver AC units can be located in on floor plantrooms, carefully ventilated, or open stair core external platforms.

Corner Plant room, with splits: Grouped AC condensers in plant rooms will often require a supplementary fan to get heat out of the plant room, as condensers have no external fan pressure (See diagram 1a and 1b). Cold air is drawn in from one façade and warm air rejected on the other façade.

See AC systems 1a, 1b, 1c, 1d, 1e, 1f and 2a, 2b, 2c, 2d

Corner Plant room, with larger VRF units: These condensers come with higher static fan, thus supplementary fan is not required (See diagram 2).

See AC systems 3a & 3b

Diagram 1a – Building Crn Plant room

Cnr Plantroom

Diagram 1b – Crn Plant Room – Layout

Cnr Plant room Layout

Diagram 2 – Building Indent Plantroom

Diagram 2

Consideration 3:

  • Balcony Located Units not allowed,
  • Building 15 to 28 levels,
  • Condensers on roof,
  • Power and Maintenance by apartment occupier

VRF Rooftop Condensers

With this driver, air conditioning can be provided from medium to large sized splits with VRF/VRV units. These ‘larger’ splits are able to cope with the higher building heights.

See AC types: 3a & 3b.

With condensers on the roof, vertical risers through the building will be required (in common areas), with access. Diagram 3a (narrow/long riser). Diagram 3 b (‘square’ shaped). For early spacial planning, typically 100mm x 100mm is allowed per apartment (1 AC condenser).

VRF Rooftop Condensers

 

Thin Refrig Riser
Diagram 3a – Refirgeration Riser – Shape 1
Rect Refrig Riser
Diagram 3b – Refigeration Riser – Shape 2

Note: If common billing and ownership was an option then AC type 4 and 7 b can be considered.

Consideration 4:

  • Balcony Located Units not allowed,
  • Building > 28 levels (90m)

With this driver, based on FF of 3.2 m (building > 90 m) AC units located on the roof become technically out of the range of large VRV/VRF units, with occupier ownership and maintenance.

On floor plant rooms as per consideration 3 are technically viable. See example below.

At this stage central plant systems are often considered, with common maintenance and common power supply requiring BMS controls and a billing system for power etc.

Common Systems:

  • Condenser Water (AC type 5)
  • Chilled Water (AC Type 6)
  • Hybrid CW to refrigeration units (AC type 7)

On Floor Plant room example.

This example allows for 2 off VRF units (2 x 28 kWr units or 1 x 28 + 1 x 33 kWr units) to serve 10 off apartments (capacity of 10 off apartness at 64.3 kWr).

The plant rooms should be located on opposite facades for each level to avoid hot air being recirculated into plant rooms above.

On Floor VRF Plantroom.png

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