Daikin GYEQ20AN Service Manual page 57

SiAUY361411EA
7 Installing the Outdoor Unit
Cautions for refrigerant leaks
WARNING
Introduction
Daikin Gas Heat Pump Air Conditioning Units use R410A as their refrigerant. R410A is a safe, nontoxic,
noncombustible refrigerant, but the room where the air conditioning unit is installed must be large enough to
prevent the refrigerant gas concentration from reaching a dangerous level if a gas leak occurs.
To address this, important points relating to R410A are presented below, along with an explanation of
conformation procedures for refrigerant concentration and relevant handling methods.
Terms and definitions
• RCL (Refrigerant concentration limit in an enclosed space)
The acceptable concentration of refrigerant, which is the maximum concentration of refrigerant in the air
specified to reduce the risk of acute toxicity, oxygen deficiency and inflammability.
• QLMV (Refrigerant concentration limit in a space with minimum ventilation)
The maximum concentration, which is not reached even with the leakage of the full refrigerant amount in a
residing space with an opening of 0.0032 m
• ODL (Refrigerant concentration limit for oxygen deficiency)
The refrigerant concentration determined to not cause any physiological abnormality due to the lack of
oxygen.
• Residing space
Residing space is defined as a space surrounded by walls, a floor and ceiling, and in which people
commonly reside for a relevant time. It does not not include the plenum space or the space under the access
floor (Fig. 1). Warehouse and storage are not considered residing space.
Device Overview
The room where the air conditioning unit is installed must be large enough to
prevent the refrigerant gas concentration from reaching a dangerous level even if a
gas leak occurs. Verify the concentration and take appropriate measures if it
exceeds a dangerous level.
2
.
Attic space
Residing space
Fig. 1 Definition of Residing Space
Refrigerant piping
Indoor unit
Space under access floor
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Installation Work Manual
0FGHP-EN0801 DGJ002
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