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Air conditioning has become such a major part of
our lives that when systems break down, we demand
that they be fixed immediately. But when this happens,
the customer needs tomake a serious decision about
whether to replace their equipment or repair it,
especially when older plant is involved.
Often, the first instinct is to call for a quick repair job.
But is this the right decision? Repairs on an existing unit
may be the least expensive short-termoption.
Installing a new, energy efficient systemmay be a better
long-termoption, both in terms of performance and
particularly operational cost.
There are many pitfalls in replacing an old air conditioning
system; it’s not just a matter of pulling an old one out and
installing a new one. If you look at a typical split ducted
unit that has failed and is 10 years old, you need to be very
mindful of the following: the old systemprobably operates
on the refrigerant HCFC 22 (R22) and contains mineral
oil in the system; while the system’s interconnecting
refrigerant pipework is only rated for R22 - amedium
pressure refrigerant.
When replacing an R22 system these days – particularly
withmany air conditioner manufacturers offering
high-pressure refrigerant HFC410a (R410a) – the
interconnecting refrigerant pipework will not be suitably
rated for R410a. Theminimum refrigerant tube wall
thickness for R410a is 0.81mm, requiring a complete piping
change. To highlight this point if you look at an R22 system,
its pressure would be 1940 kPa and an R410a systemwould
be 3045kPa at 50
˚
C saturation Pressure (abs). That’s a
big difference in pressure that reinforces the point about
using or not reusing the correct rated pipe.
With the accelerated phase out of HCFC Refrigerant
towards total ban in 2020, this is having a dramatic effect
on market prices of these gases. The cost of repairs can
sometimes be greater than the overall replacement cost
(refer to case studies for further information).
To answer the repair or replace question, several important
factors need to be addressed including:
•
Availability of replacement parts;
•
Availability and cost of refrigerant;
•
Age of the equipment;
•
Condition of the equipment;
•
How long will the air conditioner be down while
awaiting repair?
•
Labour resources;
•
Energy efficiency;
•
Owner’s budget; and
•
Is there a replacement unit available quickly
However, more efficient equipment will actually
save you money over time as it requires less fuel
to cool your home or business, especially with
a 10% – 30% increase in efficiency due to the
MEPS requirements.
Repair Or Replace
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