How to diagnose an intermittent equipment problem that only happened once
Intermittent equipment issues that disappear by the time a technician arrives are nearly impossible to diagnose because normal tests show nothing wrong. This leaves people unable to catch the problem before it worsens or get repair help for a fault that refuses to replicate on demand.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1shutting the unit off manually and turning it back on
- 2waiting for the issue to return before attempting further diagnostics
- 3monitoring suspect components
- 4Recording videos of the issue to show technicians
- 5Turning off the circuit breaker for an hour to reset it
- 6Getting a second opinion from another company
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I've had HVAC guys out multiple times, but by the time they get out to my house, the unit is running normally and they say it cools at normal levels. They said they can't really diagnose it since it's working fine while they are there.”source ↗
“I recently experienced a problem with my electric heat pump where the house temperature exceeded the thermostat cooling setting by 3 degrees.”source ↗
“I am hoping to that if the problem reoccurred to catch it before it creates a more severe problem.”source ↗
“trying to troubleshoot a problem that happened once about a week ago is like trying to find a needle in a haystack.”source ↗
Where this came up
People with this problem also raised
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- 4Why does my electrical outlet only work sometimes?
- 3Power strip sparked and tripped the breaker
- 7Why is my truck shaking and popping after replacing wheel hubs?