Gas lock is a field emergency disguised as nothing. The unit still runs. The motor still draws current. The polished rod still moves. But no fluid reaches the surface because gas is trapped between the traveling valve and standing valve and neither is opening. Production goes to zero and stays there until something breaks the lock. Here is the response sequence.
Confirm It Is Gas Lock
Fluid level shot: high annular fluid level with no production. Surface card: flat or near-flat load with very low dynamic variation. Downhole card if you can calculate one: rounded, minimal valve action, far from the sharp-cornered healthy shape. Unit sounds unusually quiet because there is no fluid work happening. If fluid level is low, this is pumped-off, not gas lock - different problem, different response.
Break the Lock
Stop the pump for 15 to 60 minutes. This is usually enough. The trapped gas migrates up the annulus, liquid returns to fill the pump, and valve action restores when you start back up. Many wells gas lock repeatedly in the morning and recover during the operational cycle on their own.
If stopping does not work, try reducing SPM temporarily. Slower strokes give the traveling valve more time to develop pressure on the downstroke and can crack the lock. Some field operators tag the pump - bottom out the rod string briefly to create a mechanical pulse that opens valves - but this risks rod damage and should be avoided if other options work.
Once the Well Is Running Again
Run a dynamometer card and fluid level shot. Document card shape and submergence. If gas lock is happening repeatedly, the pump is seeing too much free gas and no amount of operational response fixes it - the configuration has to change.
What to Change So It Does Not Recur
Add or upgrade the downhole gas separator. A properly sized gas anchor separates gas from liquid before the pump intake and is the highest-leverage fix on most gas-locked wells. Lower the pump below the perforations where rathole allows, so gas can separate naturally in the annulus. Raise the compression ratio by increasing pump spacing - a higher compression ratio clears more gas before the traveling valve stalls.
If gas is chronic and the economics justify it, install a POC that monitors for gas lock and automatically cycles the unit off for a recovery interval when it detects the pattern. Rod pumps with high-GOR wells benefit from this kind of adaptive control rather than fixed timer schedules.
When Rod Pumps Are the Wrong Tool
If gas lock recurs despite good separation and pump configuration, the well may be beyond the envelope of efficient rod lift. Gas lift, ESPs, and progressing cavity pumps each handle higher gas fractions better. Make the decision on economics, not on the pain of the current intervention.
Bottom Line
Gas lock response is stop, wait, restart, diagnose, then change the configuration so it does not repeat. The field response is the easy part. The durable fix is in separator sizing, pump setting depth, and compression ratio - and recognizing when the well is outside the envelope of what rod pumping handles well.