Size does matter | Archive Titles

Table 1: Number of systems monitored by system type and refrigeration cycle
System Type	Cooling only	Reverse cycle	Total
All-air (vav and constant volume) systems.	7	0	7
Fancoil (two-pipe and four-pipe)	5	1	6
Chilled ceilings (passive and active, beams and panels)	4	1	5
DX split (single and multiples)	6	3	9
DX vrf (three-pipe heat recovery)	0	4	4
Unitary heat pump	1	0	1
Total	23	9	32

Table 2: Average annual run-hours by system type
System type	Cooling only (hours)	Reverse cycle (hours)
All-air	4904	n/a
Fancoils	4686	7073
Chilled ceilings	3180	5308
DX split	6560	4136
DX vrf	n/a	6960
All	4919	5848

Table 3: Comparison of calculated internal gains to composite guidance values
Load type	Calculated values (W/m² treated floor area)	Composite guidance (W/m²)
Occupancy	6 to 30	20
Lighting	6 to 34	8 to 32
Small power	6 to 34	7 to 45
Total internal gains	21 to 86	37 to 90