Tenant complaint about AC Service

[Dennis S.]

I have Triplex with 2 units downstairs and 1 upstairs.  This building is about 115 years old at this point, so the insulation is probably not great.  Its something I will need to address down the road.

A few days ago I got a text from the upstairs tenant that the AC unit wasn't working in her unit.  I just happened to have my contractor in one of the downstairs units working on a rehab, so I shot him a message and he went to take a look at it the next morning.    The contractor said there was a greater then 1/4 inch layer of stuff all over the AC condenser, so cleaned that all out.     He checked it out and said everything is good.

When I spoke with the tenant she said that it had started working a little bit the night before.

Last night I got a message from her.  'The air conditioner isn't quite keeping up still.  It's set at 69 and it was 72 when arriving home just now which isn't a huge difference.  The only thing is it keeps the air conditioner constantly running so I am afraid it will make my utility bill skyrocket.'

What are your suggestions?    Do I call another guy out for a second opinion?   Do I tell her that keeping the upstairs of a 115 year old house at 69 degrees on 95 degree days is of course going to cause a high utility bill?    Just need suggestions...