If the water damage was not repaired before the warm weather arrived you will most likely have a mold problem. It helps to know where projects are located.

She has already said they have taken care of the mold issues Renovator. Are you saying they could have additional mold issues that they don't realize they have?

Nan-nan, we left our house un-heated for 3 years while we gutted the upstairs and tore off the back of the house for the addition. This house is so old though, that it has never had central heat, we are putting it in eventually, but for now it is a hand stoked coal stove. The house has never really been fully "heated" and has always had extreme hot and cold swings. We even have our pipes run so if they burst, they will hopefully (and always have) burst in the 4x8 cinder block "cellar" with sump pump. We have had pipes burst 2 times in the past 12 years and never any damage besides the pipe and the swearing of whoever has to fix it. So while we saw no ill effects, I am really not sure what you should expect there.

Where are you located? What type of heating system do you have?

I would also suggest that whatever your heating system is that you not only make sure it is in proper working order, but be sure it is clean. I did some renovation work in an apartment and didn't thoroughly clean our forced air system before re-starting it in the winter. Hubby had to do some serious repair work to it only 2 weeks after starting it because a lot of the dust had made its way into the duct work and into the system and clogged it up and burnt out some part or another.

Kali

How do you recommend cleaning out the forced air system? I have heard that duct cleaning isn't really necessary. Not sure if I believe that or not.

I would agree, duct cleaning normally isn't really necessary. We lived in that place for 10 years and that was the only year we had an issue. I had taped plastic up in our open stairwell (3 floors) and sanded the stairs and their rails down and re-finished them. I didn't realize the return register for the heating system was on the second floor stair case wall. Well, OK, I probably realized it, but didn't think anything of it. According to my husband I didn't do a very good job cleaning up the sawdust from the ceiling register and it was way more concentrated because it was my main work area and I had taped it off from the rest of the house.

But, seeing as I was doing it and knew I was doing the work and didn't think about it--- hubby knew I was doing the work (and he is pretty darn knowledgeable about these things usually) and didn't think of it, I figured I would mention it to you if you have been doing a lot of work this summer.

I would change your filter, and check and clean your returns. Don't worry about your ducts, save your money for fixing all the other issues that will come up over winter.