Amid coronavirus, what is the ideal AC temperature?
What's the story
The Central Public Works Department (CPWD) has issued a set of guidelines on the maintenance of heating and air-conditioning units amid the coronavirus pandemic. The guidelines, drafted by the Indian Society of Heating, Refrigerating & Air Conditioning Engineers (ISHRAE), recommend setting the AC temperature between 24-30°C, and maintaining 40-70% relative humidity. Read on to find out other do's and don'ts listed in the advisory.
Recommendation
All CPWD buildings asked to follow guidelines
According to The Hindu, officials in charge of all CPWD buildings in India have been asked to follow the ISHRAE guidelines. The CPWD field offices have been asked to follow the guidelines amid concerns that heating, ventilation, and air-conditioning (HVAC) systems could further spread the coronavirus disease (COVID-19). Notably, the CPWD manages offices of the Ministries in Delhi.
Room ACs
Here are the guidelines for room ACs
The ISHRAE guidelines recommend maintaining the AC room temperature between 24-30°C and relative humidity between 40-70%. For dry climates, the advisory recommends keeping a pan of water in the room to allow adequate humidity. "When we breathe dry air the mucous membrane in the lungs become dry." It also advises outdoor air intake through "slightly open windows and exhaust by natural exfiltration."
Cooler, fans
Guidelines for coolers and fans
For desert coolers, the advisory states that the water must be drained and refilled frequently. The cooler tanks must be kept clean and they must draw outdoor air to ensure good ventilation and optimum humidity. Fans should be operated with windows kept partly open, the advisory states. Exhaust fans in toilets must not allow toilet air to come in contact with other occupied spaces.
Details
Operating guidelines for commercial/industrial indoor units
The ISHRAE guidelines recommended setting the AC room temperature between 24-30°C and relative humidity between 40-70%. This must be accompanied by adequate ventilation. It is also recommended to inspect and clean indoor unit coils, keep toilet and kitchen exhaust fans in operating mode, and keep the Heat Recovery Wheel (HRW) in off mode to reduce cross-contamination. The HRW must also be sanitized upon restarting.
Details
Guidelines for operation and maintenance of HVAC system
Residential use: The room must be kept well-ventilated with fans running. For technical assistance, call the authorized technician. "In case of a major breakdown, it's advisable to request for a replacement machine to have minimum contact time with the technician." Commercial use: Get the area sanitized. Disinfect filters, grilles, diffusers, internal surfaces, condensate drain pans, coils, ducts. More details are available on ISHRAE website.