Page 29 - Towards A Sustainable Future , Phase 3 2025, E-Book_Neat

According to the BMS engineering team, if R32's suction SRD is enclosed with an IP65 weatherproof enclosure, which
pressure drops below 90 psi for more than 10 minutes, the air will be placed outdoors beside the condenser unit. It comes
conditioning system will be under low pressure. Low pressure with a Festo pressure transducer to monitor the pressure; the
has the potential for the following outcomes: pressure range can be set based on the refrigerant minimum
pressure threshold. Once low pressure is detected, a buzzer
1. Possible refrigerant leakage to the environment- Global will sound, and the red LED will be lit up to warn the user.
Warming
2. Reduce air conditioning efficiency by 10 to 20% SRD also comes with EPS 32 WIFI and Simcom A7670C sim
3. Increase energy consumption – 10 to 20% card chip on board, as shown in Fig. 3.3, enabling SRD to
4. Lower cooling capacity always connect to the internet. There is an option for the user
5. Reduce the air conditioning life span and early failure to choose SRD to be connected through WIFI or a subscription
6. Possible fire risk – R32 refrigerant is A2L gas (Flammable SIM card. During low-pressure conditions, SRD will send out
Gas) WhatsApp and email low-pressure alarm notifications to the
user and the Daikin technician. The technician will arrange with
After confirmation of low pressure, the air-conditioner is the user to check the air conditioner.
recharged with refrigerant. If the pressure gradually drops
below 90 psi within 1 week, then there is leakage in the air
conditioner. Technicians will need to check and locate the
source of the leakage. (Refer to Table 3.2)

Table 3.2 Low-pressure condition and confirm leakage conditions
Fig 3.3. ESP 32 Wi-Fi microprocessor chip and Simcom A7670C (SIM
Traditional leak detection methods (i.e., electronic leak card) chip
detector, halide detector, or soap solution) are time-
consuming and make it challenging to detect refrigerant Below (Figure 3.4) are sample emails and WhatsApp
leakage. Any factors can cause leakages, e.g., a compressor, a notifications messages sent to the user and technicians.
corroded refrigerant pipe or flare joints.

This proposed solution to detect low pressure and leakages
also mitigates fire risk in buildings. R32 is an A2L flammable gas
classified by ASHRAE and SCDF. Should a leakage be detected,
the user can choose to switch off the air conditioner and
close the refrigerant valve to prevent further R32 refrigerant
leakage into the room. A Daikin technician will also contact Figure 3.4: The Technicians and users received an email and
the user of the potential fire risk and arrange an assessment WhatsApp alarm message
appointment.

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