I have a water heater and heating system in my garage closet. These have been a problem since the house was built 10 years ago. At first air coming down the vents constantly blew out the heater. After much haggling the company came out and extended the vent pipes taller and put on different caps. This helped but did not cure the problem. over the past three years when it rains hard water comes down through the vents and is ruing the ceiling in my garage. It also sets of my fire alarm, as the water runs across the attic space, which is space between the garage ceiling and the room upstairs, the water runs down thru the heat sensor in the garage and sets off the fire alarm. I have tried everything I can think of. When I look up I can see light around the vent pipes and can see the water dripping off the internal vent. I haved caulked around the vents. Nothing seems to be loose. Can I change the type of caps on the vents?? Or maybe do something else. My roof is 29 feet high and very steep. Where the garage joins the house there is a lower roof, about 3 feet lower, the vents are right next to this overhang of the higher roof and when storms come from the north the water seems to bounce back and come down the vents.