Gas doesn't get used up
An AC's gas goes round in a sealed loop. It is not like petrol in a car. If the gas is low, it has leaked somewhere: a loose nut, a cracked pipe, a damaged coil. Topping it up without finding the leak means you may need gas again in a few weeks.
What to ask before a refill
- Show me the pressure reading on the gauge before you add gas.
- Where is the leak, and how will you fix it?
- Which gas does my AC use? (R410A, R32 or R22 — it is written on the outdoor unit's label.)
- What is the total price, including leak repair?
- Show me the reading again after the refill.
Common tricks to watch for
Some people say 'gas is finished' without connecting a gauge, or charge for a full refill when only a small top-up was added. Others add the wrong gas type. You don't need to be an expert: just ask to see the gauge and the label, and agree on the price before the work starts.
Price depends on the gas and the amount
A small top-up costs much less than a full charge after the whole system was emptied. Prices also change with the market and the gas type, so treat any number you hear as approximate and ask for the total first.