Concrete Pad – Doesn't Fit In

Last year I received a Master Cool evaporative cooler for free. I purchased some duct work from a local home improvement store but never permanently attached it. I had used duct tape to hold the whole mess together last year. Duct tape does a poor job of sticking to concrete.

This year I came up with a method of attaching the duct work by installing concrete bolts and bolting down extruded aluminum L channel to the concrete. I considered gluing the aluminum directly to the concrete but I wanted to have the option to remove it in the future.

I learned a few things about drilling through concrete. First: it takes a lot of power and my cordless Dewalt drill had a tough time with the drilling. It was just really slow (perhaps a lithium ion nano battery would have helped). I was meaning to buy a corded hammer drill anyway and the corded drill was 10 times faster. Second: it was easier to drill the holes in the aluminum L channel then use that as a template for drilling the concrete, rather than marking the concrete. The drill bit tended to walk a little in the concrete. Third: drilling concrete is hard on the drill bits. It’s good to have extra on hand.

I attached double sided window and door weather stripping to the aluminum L channel but left the paper backing on the other side. I filled in any remaining gaps with some outdoor rated silicon sealant.

I am far from done with this project. I need to verify that water is not leaking into the duct. I need to have someone clean all the duct work so I have not completely sealed the duct to the aluminum L channel. I want to install some sort of concrete sealant to the duct once it’s cleaned out.

Finally, I want to build a better stand for the cooler. I envision a wheeled stand with a built-in jack so I can easily move the cooler around for maintenance and adjust its height without additional help.

This was only the second summer I’ve lived in this house, and the second year I’ve ran the swamp cooler. I thought I was lucky to have a swamp cooler that sets on the ground instead of the roof. I expect to have some dirt get through the ducting, but i had quite a bit of it all summer long this year. I also found that the cooled air was making it out our under the concrete pad that the cooler is setting on. Summer is over, so i pulled off the swamp cooler to take a look. I found a huge mess.

The metal duct work is mostly rusted away. I would expect that the ducting would be incased in concrete, which it appears there was an attempt to do so. Except only 50% of the ducting had concrete surrounding it, the rest was up against dirt. Damp dirt, which led to the rusting and the mud which penetrated the ducting.

I pulled up the majority of rusted mess out. I allowed the pit to dry out then vacuumed up as much of the dirt with a shop vac as I could. I also found a layer of dirt in the 18 inch duct that leads to the main distribution center under the forced air heater. Thankfully that where the dirt stops.

Temporary sealing of duct work for winter

I’ve got a huge mess to clean up. I’m going to need to talk to a HVAC contractor to see what can be done. Hopefully I can do most of it myself, but I will need some advice. I decided not to deal with it this fall, instead I sealed up the main 18 duct so the heated air wont get out this summer. I took a piece of foam and a piece of plywood, sized up to the wall where the inlet to the house is, and held them with some 2×4’s that I hammered into place.The foam compresses and seems to have a good seal. I filled any other holes with pieces of foam and some expanding foam.

If your interested in following the progress, you can view pictures at a flickr set.

Tag: Concrete Pad

Attaching The Evaporative Cooler Duct Work To The Concrete Pad

The Mess That Is My Underground Duct Work