Support
Table 4: Indirect systems.
Area being cooled
System location
Max charge, A2 refrigerants
Max charge, A3
refrigerants
All areas Part or all of system below ground As below 1kg
General occupancy
Class A Whole of system at ground level or above,
compressor and receiver in open air or
machine room Apply comfort cooling / heating
practical limit 1.5kg
General occupancy
Class A Whole of system at ground level or above
and in an unoccupied machine room or
open air No restriction if exit to open air
and no direct communication
with A and B areas 5kg
Supervised occupancy
Class B Whole of system at ground level or above,
compressor and receiver in open air or
machine room No restriction if machine room
has no direct communication to
occupied space 2.5kg
Supervised occupancy
Class B Whole of system at ground level or above
and in an unoccupied machine room or
open air No restriction if machine room
has no direct communication to
occupied space 10kg
Authorised access
Class C Whole of system at ground level or above,
compressor and receiver in open air or
machine room No Restriction 25kg
Authorised access
Class C Whole of system at ground level or above
and in an unoccupied machine room or
open air No Restriction No Restriction
Table 5: Classes.
Class Location where… Examples
A People may sleep;
The number of people present is not controlled;
Any person has access without being personally acquainted with the
personal safety precautions. Hospitals and nursing homes
Prisons
Theatres, lecture halls
Supermarkets, restaurants, hotels
Transport termini
Ice Rinks
B Only a limited number of people may be assembled, some of them being Laboratories
necessarily acquitted with the general safety precautions.
Places of general manufacturing
May be a room or part of a building.
Office buildings
C Not open to the general public where only authorised persons are
granted access.
Authorised persons are acquainted with general safety precautions.
So Chris, if for example, in the case when the whole of
system is to be placed at ground level or above and in
an unoccupied machine room or open air you face no
restrictions with regards to the amount R290 refrigerant
one can use. This is easy to achieve when utilising an indirect
system.
We are therefore not necessarily limited to the 500 grams you
mentioned.
I have seen many scenarios outside of our borders where
large industrial R290 plants have been installed successfully. We
have all the fundamental knowledge required to design, install
and operate R290 equipment. With a relatively small amount of
training, predominantly around the safety issues, people at all
levels will easily adapt to R290.
www.hvacronline.co.za
Cold stores and abattoirs
Refineries
Non-public areas in supermarkets
Manufacturing facilities (e.g. chemicals, food)
Chris, I hope that this assists you with the use of flammable
refrigerants. As I said in the previous issue, they have arrived and
are certainly here to stay.
References:
1.
2.
3.
4.
ACRA
EN378
SANS10231
BRA
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with ‘Solutions Page’ in the subject line. You may include
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RACA Journal I March 2020
63