I am managing several properties and Nuki helps me with that. Recently I have been faced the same issue in at least 4 different properties with energizer lithium batteries and Nuki battery packs:
The houses have been closed during 2-3 months, then someone tries to access the apartment and suddenly a low battery notification is triggered and Nuki locks can’t open due to a lack of battery power. During these months I did not receive any battery notifications from the devices and I am sure these notifications were activated since my business depends on them. I assume that Nuki locks go into a kind of hibernation mode so it doesn’t realise the battery status till the moment someone tries to open the door after a few months.
To resolve this situation and to be aware of the battery statuses I want to develop a script to unlatch and lock the Nuki locks periodically so Nuki locks can wake up and notify if the batteries are low beforehand some goes to the apartments. Unfortunately, I have found a second problem with developing this simple script, depending on the smart lock configuration, if the door works with a knob or handle on the other side, the unlock [/smartlock/{smartlockId}/action/unlock] of the API actually opens the door instead of just unlatching according to the section 6.1 of the API doc. As a result, I cannot develop this script to wake up my devices since I risk left opened the properties.
Do you know any other way to resolve this situation?
No. The Smart Lock checks periodically the state of the batteries and updates the notification flag if needed. However there are 2 different detection modes for low batteries: 1) Is based on the voltage at rest and 2) is based on the battery behavior during lock commands.
Voltage at rest could be problematic especially with Lithium batteries or with cold conditions (low temperatures). But the Nuki Powerpack should not have such issues. I will ask a colleague to contact you and have a look at your case.
No. Unlock will always only unlock, independent of the knob/handle setting. So it is safe to call an unlock / lock command sequence. But this has other side effects like quicker battery drain and possible guests being frightened by the automatic operation of the lock (if it is not deactivated when they are there).
I have tested the unlock API call against my Nuki lock at home and it opens the door. It is not just unlocked but open. Actually, that is what I see in the documentation, Did I misunderstand the info in the picture?
I agree with the battery drain side effects or frightening guests (I can avoid doing it during bookings) but I have no chance. I cannot afford the situation of having people that cannot enter at home due to that Nuki behaviour. Temperatures are not that low in my region and some door are inside buildings that keep the temperature.
How would you manage this situation? I mean, maybe you have a better way to deal with this.
You need to send the lock action command with action = 2. See: Swagger UI
Using the simple lock action does not provide the result you want (i.e. it will unlatch when you have a knob setting).
If the problem is not a bug on our side, there is no better way than to lock from time to time (e.g. once every week) to check if everything is still ok.