Is there an easy way to correct this ‘blip’?!
Yes.
There is always a way, it is data after all. The question is how much work do you want to do? You didn’t mention what persistence layer you were using, so here are a few:
rrd:
remove spikes
rrdtool dump and restore
If sql, just use your favorite sql tool, or sqllite comes with its own.
Just to avoid possible wasted time, my understanding is that the rrd4j files not compatible with rrdtool. To verify, I’ve tried opening an rrd4j file with rrdtool with no success.
So is there a way that works to remove spikes in charts?
Run Java inspector. To edit, best to shutdown OpenHAB to prevent sync/collision errors.
Execute $: java -cp rrd4j-2.1.1.jar org.rrd4j.inspector.RrdInspector
(inside the openhab/lib, then a nice GUI is shown).
One can (also) use the API/REST interface to search for extraneous values.
http://your.openhab.:accessport/doc/index.html#!/persistence/httpGetPersistenceItemData
Note: use rrd4j as service-id and (of course) type your specific persisted item/table-name.