Overview
DX (Direct Expansion) Unit in an Air Handling Unit (AHU) is an HVAC system that uses a DX coil inside the AHU to directly cool or heat the air using refrigerant. Unlike chilled water AHUs, which require a chiller and water loop, a DX AHU operates with a refrigerant cycle, making it a compact, cost-effective, and efficient solution for small to medium-sized buildings.
Parameter
Cooling, water volume, water resistance
Cooling conditions: Inlet air dry bulb temperature 27℃, wet bulb temperature 19.5℃, inlet water temperature 7℃, outlet water temperature 12℃
|
Model |
Two-row pipe |
Four-row pipe |
six-row pipe |
eight-row pipe |
||||||||
|
cooling(KW |
Water volume(m³/h) |
Water resistance (KPa) |
cooling(KW) |
Water volume (m h) |
Water resistance (KPa) |
cooling(kW) |
Water volume (m³/h) |
Water resistance (KPa) |
cooling (KW |
Water volume (m³/h) |
Water resistance (KPa) |
|
|
ZK-05 |
18.8 |
3.23 |
10.1 |
29.4 |
5.01 |
9.76 |
37.8 |
6.49 |
16.99 |
45.7 |
7.85 |
10.44 |
|
ZK-10 |
34.7 |
5.89 |
10.5 |
58.6 |
10.35 |
11.65 |
75.4 |
12.96 |
10.08 |
91.2 |
15.70 |
12.82 |
|
ZK-15 |
53.4 |
9.16 |
9.8 |
87.9 |
15.08 |
7.21 |
113.1 |
19.5 |
12.11 |
136.8 |
23.52 |
15.12 |
|
ZK-20 |
70.6 |
12.14 |
9.8 |
117.3 |
20.16 |
8.25 |
150.8 |
26.21 |
14.07 |
182.4 |
31.96 |
17.48 |
|
ZK-25 |
92.9 |
15.83 |
11.6 |
146.1 |
25.12 |
10.24 |
188.1 |
33.90 |
11.77 |
227.5 |
39.11 |
14.76 |
|
ZK-30 |
113.6 |
19.2 |
11.8 |
175.2 |
30.12 |
11.16 |
225.6 |
38.90 |
13.10 |
273.4 |
47.00 |
16.28 |
|
ZK-40 |
144.4 |
24.82 |
12.4 |
232.8 |
40.03 |
12.93 |
300.2 |
51.61 |
15.73 |
362.2 |
62.27 |
19.20 |
|
ZK-50 |
180.5 |
30.61 |
10.4 |
292.3 |
50.25 |
7.47 |
375.3 |
64.52 |
17.00 |
435.80 |
74.93 |
15.70 |
|
ZK-60 |
216.6 |
37.24 |
9.4 |
349.2 |
60.04 |
7.47 |
450.3 |
77.42 |
17.00 |
544.80 |
93.67 |
15.70 |
|
ZK-80 |
287.2 |
49.1 |
9.1 |
464.6 |
79.88 |
8.5 |
598.4 |
102.89 |
19.5 |
724.8 |
124.62 |
17.9 |
|
ZK-100 |
357.0 |
61.38 |
9.5 |
578.2 |
99.41 |
8.5 |
746.5 |
128.35 |
19.5 |
904.2 |
155.46 |
17.9 |
|
ZK-120 |
428.4 |
73.65 |
9.5 |
693.6 |
118.91 |
8.5 |
895.2 |
153.91 |
19.5 |
1084.8 |
186.51 |
17.9 |
|
ZK-160 |
591.2 |
101.65 |
11.2 |
921.6 |
158.48 |
10.3 |
1190.4 |
204.67 |
20.1 |
1443.2 |
255.93 |
32.4 |
|
ZK-200 |
740.1 |
127.25 |
12.8 |
1152.2 |
199.3 |
13.1 |
1488.1 |
255.86 |
26.4 |
1804.3 |
310.22 |
42.4 |
Note: The performance parameters of the unit at a headwind speed of 2.5m/s
Cooling condition correction factor
Correction Factor K1 for Cooling Capacity and Water Flow under Different Inlet Air and Water Temperatures
|
air temperature |
Water temperature℃ |
|||||
|
Wet bulb Temperature |
Dry bulb Temperature |
5/10 |
6/11 |
7/12 |
8/13 |
9/14 |
|
17 |
19-27 |
0.83 |
0.76 |
0.67 |
0.62 |
0.57 |
|
18 |
20-30 |
0.94 |
1.85 |
0.76 |
0.68 |
0.58 |
|
19 |
21-31 |
1.07 |
0.97 |
0.88 |
0.79 |
0.71 |
|
19.5 |
21-33 |
1.15 |
1.06 |
1.00 |
0.86 |
0.78 |
|
20 |
22-33 |
1.20 |
1.10 |
1.03 |
0.90 |
0.81 |
|
21 |
23-36 |
1.34 |
1.24 |
1.14 |
1.03 |
0.93 |
|
22 |
24-39 |
1.48 |
1.38 |
1.28 |
1.18 |
1.07 |
|
23 |
25-42 |
1.63 |
1.53 |
1.43 |
1.32 |
1.22 |
|
24 |
26-45 |
1.79 |
1.69 |
1.59 |
1.47 |
1.36 |
|
25 |
27-48 |
1.75 |
1.64 |
1.53 |
||
|
26 |
28-48 |
1.92 |
1.81 |
1.70 |
||
|
27 |
29-48 |
2.09 |
1.98 |
1.87 |
||
|
28 |
30-50 |
2.26 |
2.16 |
2.05 |
||
|
29 |
31-52 |
2.40 |
2.32 |
2.2 |
||
Correction Factor K3 for Cooling Capacity and Water Flow under Different Inlet Air and Water Temperatures
|
Headwind speed |
2.0 |
2.3 |
2.5 |
2.7 |
3.0 |
3.3 |
3.5 |
|
coefficient |
0.81 |
0.92 |
1.0 |
1.07 |
1.17 |
1.26 |
1.32 |
Correction Factor K2 for Water Resistance under Different Inlet Air and Water Temperatures
|
air temperature |
Water temperature℃ |
|||||
|
Wet bulb Temperature |
Dry bulb Temperature |
5/10 |
6/11 |
7/12 |
8/13 |
9/14 |
|
18 |
20-30 |
0.90 |
0.74 |
0.60 |
0.49 |
0.36 |
|
19 |
21-31 |
1.13 |
0.95 |
0.77 |
0.65 |
0.54 |
|
19.5 |
21-33 |
1.35 |
1.15 |
1.00 |
0.78 |
0.63 |
|
20 |
22-33 |
1.41 |
1.20 |
1.05 |
0.82 |
0.67 |
|
21 |
23-36 |
1.72 |
1.49 |
1.27 |
1.06 |
0.86 |
|
22 |
24-39 |
2.08 |
1.82 |
1.57 |
1.34 |
1.12 |
|
23 |
25-42 |
2.48 |
2.20 |
1.93 |
1.66 |
1.14 |
|
24 |
26-45 |
2.95 |
2.62 |
2.33 |
2.03 |
1.76 |
|
25 |
27-48 |
2.78 |
2.46 |
2.16 |
||
|
26 |
28-48 |
3.30 |
2.94 |
2.60 |
||
|
27 |
29-48 |
3.80 |
3.50 |
3.12 |
||
|
28 |
30-50 |
4.14 |
4.10 |
3.70 |
||
|
29 |
31-52 |
4.14 |
4.10 |
3.70 |
||
Correction Factor K4 for Water Resistance under Different Inlet Air and Water Temperatures
|
Headwind speed |
2.0 |
2.3 |
2.5 |
2.7 |
3.0 |
3.3 |
3.5 |
|
coefficient |
0.9 |
0.96 |
1.0 |
1.04 |
1.1 |
1.16 |
1.2 |
Ps:1.The above correction factors are determined based on the average values of various units. For small units (05~15), multiply by 0.95; for large units (50-200), multiply by 1.08.
2.The above correction factors are approximate values and are for reference only.
Correction under different wind speeds, inlet air temperature, and water temperature conditions:
Actual cooling capacity = Cooling capacity from Table 1 × K1 × K3
Actual water flow = Water flow from Table 1 × K1 × K3
Actual water resistance = Water resistance from Table 1 × K2 × K4
Example: Selecting YG-20 air conditioner, the cooling coil face wind speed is 2.5 m/s. According to Table 1, the cooling capacity is 150.8 kW, water flow is 26.21 m³/h, and water resistance is 14.07 kPa. Determine the actual cooling capacity, water flow, and water resistance when the inlet air dry-bulb temperature is 27°C, wet-bulb temperature is 21°C, inlet water temperature is 7°C, and outlet water temperature is 12°C.
Solution: From Table K1, the correction factor K1 = 1.14. From Table K2, the correction factor K2 = 1.27.
Therefore:
Actual cooling capacity (Q) = Standard condition cooling capacity × K1 = 150.8 × 1.14 = 171.91 kW
Actual water flow (V) = Standard condition water flow × K1 = 26.21 × 1.14 = 29.88 m³/h
Actual water resistance (P) = Standard condition water resistance × K2 = 14.07 × 1.27 = 17.87 kPa
Heating, water volume, water resistance
Heating conditions: air inlet temperature 15℃, water inlet temperature 60℃
|
Model |
Two-row pipe |
four-row pipe |
six-row pipe |
eight-row pipe |
||||||||
|
Heating(KW) |
Water volume (m/h) |
Water resistance (KPa) |
Heating (KW |
Water volume (mh) |
Water resistance (KPa) |
Heating (KW) |
Water volume (m³h) |
Water resistance (KPa) |
Heating(KW) |
Water volume m/h) |
Water resistance (KPa) |
|
|
ZK-05 |
34.1 |
3.23 |
10.1 |
50.6 |
5.01 |
9.76 |
59.2 |
6.49 |
16.99 |
77.1 |
7.85 |
10.44 |
|
ZK-10 |
67.1 |
5.89 |
10.5 |
99.8 |
10.35 |
11.65 |
124.8 |
12.96 |
10.08 |
151.0 |
15.70 |
12.82 |
|
ZK-15 |
101.8 |
9.16 |
9.8 |
149.7 |
15.08 |
7.21 |
173.5 |
19.5 |
12.11 |
205.1 |
23.52 |
15.12 |
|
ZK-20 |
135.6 |
12.14 |
9.8 |
199.0 |
20.16 |
8.25 |
248.8 |
26.21 |
14.07 |
289.3 |
31.96 |
17.48 |
|
ZK-25 |
168.7 |
15.83 |
11.6 |
249.5 |
25.12 |
10.24 |
311.2 |
33.90 |
11.77 |
353.3 |
39.11 |
14.76 |
|
ZK-30 |
202.6 |
19.2 |
11.8 |
304.5 |
30.12 |
11.16 |
380.9 |
38.90 |
13.10 |
448.3 |
47.00 |
16.28 |
|
ZK-40 |
270.4 |
24.82 |
12.4 |
399.2 |
40.03 |
12.93 |
480.8 |
51.61 |
15.73 |
592.4 |
62.27 |
19.20 |
|
ZK-50 |
337.3 |
30.61 |
10.4 |
512.3 |
50.25 |
7.47 |
556.8 |
64.52 |
17.00 |
641.8 |
74.93 |
15.70 |
|
ZK-60 |
404.7 |
37.24 |
9.4 |
609.4 |
60.04 |
7.47 |
581.2 |
77.42 |
17.00 |
766.8 |
93.67 |
15.70 |
|
ZK-80 |
539.5 |
49.1 |
9.1 |
796.0 |
79.88 |
8.5 |
386.2 |
102.89 |
19.5 |
1006.0 |
124.62 |
17.9 |
|
ZK-100 |
674.5 |
61.38 |
9.5 |
985.1 |
99.41 |
8.5 |
1127.6 |
128.35 |
19.5 |
1272.3 |
155.46 |
17.9 |
|
ZK-120 |
808.9 |
73.65 |
9.5 |
1185.9 |
118.91 |
8.5 |
1362.5 |
153.91 |
19.5 |
1533.6 |
186.51 |
17.9 |
|
ZK-160 |
1077.8 |
101.65 |
11.2 |
1576.0 |
158.48 |
10.3 |
1688.4 |
204.67 |
20.1 |
2083.2 |
255.93 |
32.4 |
|
ZK-200 |
1346.2 |
127.25 |
12.8 |
1970.8 |
199.3 |
13.1 |
2032.7 |
255.86 |
26.4 |
2606.2 |
310.22 |
42.4 |
Note: 1. The unit's performance reference at a headwind speed of 2.5m/s
2. The coil is a dual-purpose coil for hot and cold applications
Key Features of AHU DX Unit
✅ Direct Refrigerant Cooling & Heating
Uses a DX coil instead of a water-based cooling coil.
Refrigerant evaporates in the coil to absorb heat (cooling mode) or condenses to release heat (heating mode).
✅ Eliminates the Need for Chillers & Cooling Towers
No need for a chilled water system, pumps, or extensive piping, reducing installation complexity.
✅ Compact & Space-Saving Design
Ideal for buildings with limited mechanical space and retrofit projects.
✅ Fast Cooling & Heating Response
DX systems respond quickly to temperature changes, improving comfort and efficiency.
✅ Zoned Cooling & Heating
Multiple DX AHUs can serve different areas independently, improving energy efficiency.
✅ Lower Installation & Maintenance Costs
Fewer components compared to water-cooled systems, leading to simplified maintenance.
Applications of AHU DX Unit
✔ Commercial Buildings – Offices, hotels, retail spaces, and restaurants.
✔ Residential Buildings – Apartments, condos, and townhouses.
✔ Healthcare & Educational Facilities – Hospitals, clinics, schools, and universities.
✔ Industrial & Data Centers – Where precise temperature control is needed.
FAQ
Q: Can I request early shipment?
Q: Are there any special requirements for OEM purchases?
Q: What are your advantages compared to your competitors?
2. We offer reliable quality control.
3.We have competitive prices.
4.We provide efficient service (26*7 hours).
5.We offer one-stop services.
Q: Can you provide drawings and technical data?
Q: Are your products exported?
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