Thats pretty obvious what they are saying once you read the whole manual.
My take on this is:
1. Device monitors 2 sets of temperature and fan speeds, simultaneously.
2. & 3 - correct English.
4. When device detects "over temperature" the relevant LCD display will flash and audible alarm will sound.
To fix [aka shoot the trouble/troubleshoot] - Make "temperature" of the monitored device lower than original setting you set. Once this happens the alarm and flashing display indication will cease.
The [audible] alarm will auto-silence after 30 seconds, but LCD will display alarm condition until temperature reduces below original setting.
5. Low speed fan monitor - same as 4, but for fan speed.
Note: Fan speed has to increase above the setting to cancel alarm condition when it occurs. Audible alarm will silence after 30 seconds if fan speed still too slow.
Display of alarm confition will continure however until you fix [shoot the trouble of ] the fan speed problem.
6. If temperature or fan speed monitoring condition is NOT set, LCD display shows "--" for relevant condition, and no alarms will occur for this condition [either fan speed or temperature].
7. correct English.
Of course, once the over temperature of fan speed problem occurs, the first you'd probably do is shut the PC/Server down and investigate, so the unit will cease working [I assume its PC powered].
So the auto silencing/cancelling alarms is probably not so useful.
Also, seems a little useless that the device can't remember its settings between "resets".