Not Cold After Servicing
A unit stopped working two days after a routine service. Another contractor blamed catastrophic failure, but we traced it back to a simple, easily fixed service error.
Case Details
The Assessment
When servicing causes immediate failure, it's rarely coincidence. We started by checking what the previous contractor did during the service, then traced the cooling circuit systematically.
- Compressor was running normally with no overheating signs
- Refrigerant pressure looked normal — gas level was not the issue
- Found an outdoor service valve not fully reopened after servicing
- Restricted refrigerant flow was blocking normal cooling
The Diagnosis
During a routine service, technicians sometimes close valves to check pressure or isolate the indoor unit. The valve must be fully reopened after. In this case, it was left partially closed. Enough for the system to run, but not enough for gas to flow. The compressor was fine. The cooling circuit was blocked by a valve a couple of turns short of open.
Fully reopen the valve, then verify if cooling returns. If cooling normalises, no parts are needed. If not, continue diagnosis from there. Start with the simplest testable cause first.
The Outcome
We opened the valve fully. Within minutes, the unit was blowing cold air. Temperature drop measured normal. Client only needed the assessment and correction — not a major replacement. Unit has been running fine since.
Timeline
What This Means for You
Did this happen to you?
- Aircon was working fine before servicing
- Immediately after the technicians left (or later that day), all cooling stopped
- Indoor unit blows air but it's completely warm
If yes, the fault is almost certainly related to the service visit — likely a closed valve or a loose wire. Have them re-check their work before paying for new parts.