[COVID-19] Guideline for Operation Management and Use of Air Conditioners in Summer

This Guideline is specially formulated to scientifically guide and standardize the operation and management of air conditioners in offices, public places and residences, so as to effectively reduce the risk of transmission of COVID-19.

 

This Guideline applies to central air-conditioning and ventilation systems (including all-air air-conditioning systems, fan coil units plus fresh air systems, fan coil units without fresh air systems, and variable refrigerant flow (VRF) systems), and split-type air conditioners in offices, public places, and residences in summer.

 

 

 

1 Understand the source and supply range of fresh air, and strengthen personnel training.

 

2 Normal operation of the filtering equipment should be checked. The open cooling tower and air treatment units should be cleaned and disinfected, and air ducts should also be cleaned when conditions permit. The cleaning and disinfection of air conditioning systems should be carried out by professionals as the first choice and hygienic quality of air supplied should be tested when conditions permit. The tests results should meet the requirements of national standards and regulations, such as the Hygienic Management Regulations for central Air Conditioning and Ventilation Systems in Public Places (WS 394-2012).

 

3 Keep the fresh air inlet and its surrounding environment clean, so that the fresh air will not be polluted.

 

4 Keep a certain distance between the fresh air inlet and the exhaust port to avoid short circuits.

 

 

1 Returning air should be turned off in medium-risk and high-risk areas. If a medium and high-efficiency and above-level filtering device is used in the return air pipe or air-conditioning box, or an effective disinfection device is installed, the return air can be turned down.

 

2 It is recommended that the indoor temperature should not be lower than 26℃. To help meet the requirements of indoor temperature regulation, it is suggested that the doors and windows should not be completely closed when the air conditioner is running.

 

3 When an air conditioning system is used in a crowded place, indoor air flow should be enhanced. Priority can be given to opening windows, doors or ventilation devices such as fans, or the place may be ventilated for about 20-30 minutes every 2-3 hours of air conditioning operation.

 

4 For shopping malls, office buildings, underground garages and other places with a large flow of people, ventilation should be strengthened; and after the end of daily business the fresh air and exhaust systems of the air conditioning system should continue to operate for a period of time.

 

5 Strengthen the sanitation management of condensate water and cooling water of cooling tower in air treatment units and fan coils.

 

6 Regularly clean, disinfect or replace the filters, tuyere, air treatment units, surface air cooler, heater (humidifier), condensate tray and other equipment and components of the air conditioning system in operation.

 

7 U-shaped pipes such as sewer pipes, water seals of air treatment devices, toilet floor drains, and condensate drain pipes of air-conditioning units should be regularly checked to replenish water and avoid water shortage.

 

 

 

1 Grasp the source and supply range of fresh air.

 

2 The normal operation of the filtering equipment, surface air cooler, heater (humidifier) and fan coils units should be checked; the open cooling tower and air treatment units and condensate tray should be cleaned and disinfected and air ducts should also be cleaned when condition permits. The cleaning and disinfection of air conditioning systems should be carried out by professionals.

 

3 Ensure that fresh air comes directly from the outside, and do not deplete air in the machine room, corridor and ceiling. Keep the fresh air inlet and its surrounding environment clean, so that the fresh air will not be polluted.

 

4 Fresh air systems should be operated all day.

 

5 Keep a certain distance between the fresh air inlet and the exhaust port to avoid short circuits.

 

6 Ensure normal operation of exhaust air system.

 

7 For large rooms, measures should be taken to ensure ventilation; if the fresh air volume is insufficient (below the national standard of 30m3/h. per person), the number of people using the rooms should be reduced.

 

1 It is recommended that the indoor temperature should not be lower than 26℃. If indoor thermal comfort can be satisfied, it is suggested to open the door or windows when the air conditioning is running.

 

2 For shopping malls, office buildings, underground garages and other places with a large flow of people, ventilation should be strengthened; and after daily business ends the fresh air and exhaust systems of the air conditioning system should continue to operate for a period of time.

 

4 Strengthen the sanitation management of the condensate water and cooling water in the air conditioning system and other areas prone to pollution.

 

5 Regularly clean, disinfect or replace the cooling tower, air treatment units, air inlet, condensate tray and other equipment and components of the air conditioning system in operation.

 

6 Strengthen the inspection of U-shaped pipes such as sewer pipes, water seals of air treatment devices, and toilet floor drains so as to replenish water in time and prevent air mixing on different floors.

 

 

1 Disconnect the power supply of the air conditioner.

 

2 Wipe the dust off the air conditioner shell with wet cloth without dripping water.

 

3 Open the cover plate according to the instructions of the air conditioner, remove the filter screen, rinse away the dust on the filter screen with tap water, and dry in the air or wipe it with dry cloth.

 

4 Install the filter screen and close the cover plate.

 

5 Connect the power supply and turn on the air-conditioning refrigeration mode to check whether the air-conditioning can operate normally.

 

 

1 Before using the split-type air conditioner every day, open the doors and windows to ventilate for 20-30 minutes, and then turn on the air conditioner. It is recommended to adjust the maximum air volume to run for more than 5-10 minutes before closing the doors and windows. After the split-type air conditioner is turned off, open the doors and windows to ventilate again.

 

2 If a split-type air conditioner is used for a long time in a crowded place (such as a conference room), the place must be ventilated for about 20-30 minutes every 2-3 hours of air conditioning operation.

 

3 It is recommended that the indoor temperature should not be lower than 26 ℃. To help meet the requirements of indoor temperature regulation, it is suggested that doors and windows should not be completely closed when the air conditioner is running.

 

 

For related operation and management requirements, please refer to the split-type air conditioner.

 

When confirmed cases and suspected cases of COVID-19 are found in the venue, the following measures should be taken:

1 Immediately shut down the central air-conditioning and ventilation system corresponding to the active areas of confirmed cases and suspected cases.

 

2 Under the guidance of the local disease control department, the central air conditioning and ventilation system in the above areas should be forcibly disinfected and cleaned immediately, and only re-activated after passing  hygiene inspection and evaluation.

 

3 The cleaning and disinfection of the central air conditioning and ventilation system should meet the requirements of the Code for the Cleaning and Disinfection of Central Air Conditioning and Ventilation Systems in Public Places (WS 396-2012).