Asking Tenant to Monitor AC Usage

[Erin B.]

My husband and I purchased a multi-family unit a little over a year ago which we live in on the 2nd and 3rd floor and we rent out the 1st floor. Our first tenant was already living in the 1st floor apartment when we bought the house. 

Our first tenant moved out to move to another city and we have new (young 23-24 yrs old) tenants who moved in a few weeks ago and I'm already concerned about quite a few things we've experienced (telling us they had 1 cat when they have 2 and finding this out after they filled out the lease paperwork, dog waste in the yard, animal smell in the front hallway, never ending laundry in the free laundry facility in the basement). I am giving a little extra background info here to help with the full picture of my question...

All utilities with the unit are included (everything runs on the same meter and we have no way to separate the charges to calculate usage). We provide a window AC unit for the summer months as we're in Pittsburgh and it gets really hot and muggy. We are installing the window unit this evening and with all of the other fairly minor complaints I mentioned above, I am looking for advice on asking them kindly to monitor their usage.with the AC Unit.  

It is a standard electric window unit so putting a lock on it to keep in above a certain temperature is not and option, and we cannot separate the electric bill since we've already listed utilities as included in the lease and all of the electric runs on the same meter. 

I was thinking of asking if they could please be considerate of their usage for consideration of energy costs and if they aren't in the apartment for extended periods of time that they either keep the temperature at a higher degree or even shut the unit off. My husband suggested we just install the unit and see how its goes for the first week, saving any hassle if they are responsible about the usage. I'm concerned, one, if we let it go for a few weeks and they aren't responsible then the electric bill will be through the roof, and two that it will be more difficult to ask them to cut back on the usage after we already let it go. 

Any suggestions anyone could provide are really appreciated!

Thank you!