Overview
This document details sound levels and capacity reduction ratios for various Fujitsu VRF systems when operating in Low Noise Mode (Level 1 & 2).
The data applies to models within the J-IIS, J-II, J-III, J-IV, J-IVL, J-IIIL, VR-II, VR-IV, and V-III series used in Australian installations.
Low Noise Mode reduces fan and compressor speed, achieving quieter operation at the expense of cooling/heating capacity.
1. J-IIS Series (AJT...)
| Mode | Capacity | SPL Reduction | Power Level Reduction |
|---|---|---|---|
| Low Noise Level 1 | 71–95% of nominal | ~3 dB(A) lower | ~2 dB(A) lower |
Example (5HP unit):
Normal: 53 dB(A)
Low Noise: 51 dB(A)
Cooling capacity ≈ 95%
2. J-IVS Series (AJT...)
| Mode | Capacity | SPL Reduction | Power Level Reduction |
|---|---|---|---|
| Low Noise Level 1 | 83–97% | ~3–5 dB(A) lower | ~2–4 dB(A) lower |
3. J-II / J-III Series (AJY...)
| Model | SPL (Normal) | SPL (Low Noise 1) | Capacity % |
|---|---|---|---|
| 4HP–6HP | 50–55 dB(A) | 45–47 dB(A) | 60–104% (varies by size & load) |
Sound Power Level:
Drops from 66–71 dB(A) to 59–61 dB(A)
.
4. J-IV Series (AJY...)
| Mode | SPL | Capacity |
|---|---|---|
| Normal | 50–56 dB(A) | 100% |
| Low Noise 1 | 45–47 dB(A) | 82–108% (depending on load) |
5. J-IIIL & J-IVL Series (AJY...)
Both models share similar acoustic and performance characteristics.
| Mode | SPL | Capacity (%) |
|---|---|---|
| Low Noise 1 | –3 dB(A) vs Normal | 80–91% |
| Low Noise 2 | –6 dB(A) vs Normal | 49–62% |
Example (12HP J-IIIL):
Normal: 59 dB(A)
Low Noise 1: 55 dB(A)
Low Noise 2: 50 dB(A)
VRFSPLatLowNoiseMode20210422
6. VR-II Series (AJT...)
| Mode | SPL | Capacity (%) |
|---|---|---|
| Low Noise 1 | 51–55 dB(A) | 63–82% |
| Low Noise 2 | 48–50 dB(A) | 47–82% |
Example (14HP unit):
Normal = 61 dB(A) → Level 1 = 55 dB(A) → Level 2 = 50 dB(A)
7. VR-IV Series (AJT...)
| Mode | SPL | Capacity (%) |
|---|---|---|
| Low Noise 1 | 51–55 dB(A) | 74–89% |
| Low Noise 2 | 48–50 dB(A) | 58–69% |
8. V-III Series (AJY...)
| Mode | SPL | Capacity (%) |
|---|---|---|
| Low Noise 1 | 51–55 dB(A) | 63–94% |
| Low Noise 2 | 48–50 dB(A) | 47–76% |
Example (10HP model):
Normal: 58 dB(A)
Low Noise 1: 53 dB(A)
Low Noise 2: 50 dB(A)
General Observations
Each Low Noise Level reduces sound pressure by 3–6 dB(A).
Level 1 typically reduces output capacity by 10–20%, while Level 2 can reduce up to 40–50%.
J-series units (compact VRF) show slightly less capacity loss compared to VR-series (larger systems).
Sound Power Levels are approximately 15–20 dB(A) higher than the corresponding Sound Pressure Levels (as measured at 1 m distance).