Crawlspace conditioned air 4 unit condo

[whatever419]

In November I posted a number of questions here re the proposed conditioning of (connected) crawl spaces under our small Bloomington, Indiana condo building. With the help offered here and that of the local Buildings Department, the plan was abandoned by the HOA and they opted to stick with the passive vented system (probably with the vents closed year round).

Bloomington average temperatures http://pics2.city-data.com/w1q/lhaq7716.png

Bloomington average humidity http://pics2.city-data.com/w2q/humq7716.png

New issue: Conditioning the crawls is being considered for another condo building with 4 street level units and 4 second floor units - but the crawls are separate (not connected). One thing that I wonder about is if a unit gets rented, the renters may have little interest in (or even know about) maintaining appropriate settings. Also, there seems a rather frequent turnover of these units and I question whether buyers would be made aware of their part in this humidity control "system." One unit is owned by a company that keeps it for occasional use by visiting employee(s) - IOW, it may be vacant for extended periods.

Question: If the street level unit owners agree to allowing use of their HVACs to condition the space below them, what might be issues to keep in mind?

[Marc]

Perhaps the conditioning of the crawls is a burden only to install and lacks significant maintenance costs as your post seems to have assumed.

Marc

[whatever419]

Perhaps the conditioning of the crawls is a burden only to install and lacks significant maintenance costs as your post seems to have assumed.

Marc

Thanks, but it isn't costs that I wonder about. My concern is residents leaving the units vacant for extended periods with HVACs set at minimum settings (or with AC turned off during a summer away from the unit) - my question being: Given changing weather conditions, is it likely that the lack of attention or oversight during such absences would affect humidity/vapor issues in the crawl and potentially lead to mold, etc.?