Grafana alerts not triggered

Grafana version : 5.1.3
Datasource: InfluxDB
OS: Ubuntu 16.04
Use case: Alert configured with:

Evaluate every 10s
When: min() OF Query(A, 15m, now) IS ABOVE 25

Expected behavior: Alert should have been triggered when temperature was way above threshold for over an hour.

Actual behavior: No alert triggered.

Metric query: SELECT "temperature" FROM "foo" WHERE ("deviceId" = 'device1' AND "tag2" = '1234325') AND $timeFilter