External Air Blower Motor, Tropic-Air Replacement

In order to disassemble this kind of blower, the screws that are holding on the top, (located underneath the edge), must be removed. These are usually phillips head or 5/16" hex screws. Note the rust that has accumulated around the old motor housing (right).

At this point, we have to remove the foam insulation surrounding the motor itself. The foam usually serves two purposes... 1, to reduce the noise emanating from the blower housing, and 2, to prevent bugs and other debris from being sucked into the blower air impeller.
Normally it will work fine without this insulation, but if you can, try to preserve and re-install it.

With the foam removed, now it's time to remove the motor and retaining mount from the main housing. This requires a 5/16" nut driver as shown on the left. Usually there will be 4 screws on the bottom of the blower holding it in. To finish separating the blower motor frame from the housing, I use a flat-headed screwdriver to pry the assembly apart.

Once a little bit of force is applied to the housing, it usually separates quite easily.

With the blower motor mounting frame detached from the rest of the housing, the first thing to do is to remove the green ground wire attached to the motor frame itself. Then, remove the four screws holding the plastic motor mounting ring, (right), using a 5/16" nut driver.

Now we can remove the blower motor. Because of size constraints, the brush assemblies must be hand maneuvered through the small hole.

Removal of the old motor is now complete

Installing the new motor is quite easy at this point, simply maneuver the wiring and the motor through the access hole in the motor mount. Be careful not to damage the brush assemblies.

On the left, we've got the motor and mounting assembly sitting in the correct position. On the right, we're re-installing the 5/16" screws that will hold the assembly together.

Now we've got to thread the motor wires to the connection compartment. First I trim them to the appropriate length, and thread them through the housing. (This may seem odd, but I only do this as a demonstration in case the wires in your particular blower configuration are too short. Check yours first before cutting the new wires).

With all of that completed, connecting the wires and setting every thing else electrical wise is in order now. The 3 wires coming from the main compartment must be connected to the blower motor. Don't forget the ground wire! I usually prefer to twist them together, connect a wire nut, then tape them up with electrical tape. Then, to prevent the blower air from untwisting them, tie the entire group of wires together with a nylon tie-wrap.

Because the electrical connections are in the same compartment/area as the rotating armature, it is important to make sure that everything in this area is minimalized. The least amount of wire, means the least amount of problems. Using a nylon tie wrap to prevent the unravelling of the electrical tape, and keeping the wire assembly intact is important here. Use common sense!
If the wires on your blower motor are long enough, you may not have to perform this patch, simply route the new wires through the housing. Don't forget the ground wire though!

Once the assembly of the motor to the housing is complete, it is prudent to reseal the lower blower cavity with silicone sealant. Without it, this thing would probably whistle so loud that it would drive neighbors crazy 3 blocks down.

Now, I carefully thread the three blower motor wires through the access hole to the connection box, and pull them in a reasonable amount to ensure that air movement won't cause interference between the rotating armature, and the wires inside. This must be done simultaneously with assembling the blower housing. Afterwards, it's a good idea to make a visual check through the blower exhaust to ensure that none of the wires are liable to make contact with the rotating armature. Everything done? Now re-install the through bolts and tighten the nuts down.

With the discharge assembly complete, I re-use the foam strips and install them with silicone.

It is important to try to re-use the foam, simply because it is the most important part of noise reduction. The blower will work without it... only it'll be a bit louder.

Make a judicious inspection of the noise reducing foam in the blower intake cap. If it's loose or coming apart, go ahead and remove and replace it, or re-install it using silicone adhesive. Finally, re-install the screws from the suction part of the housing.
Reassembly of the blower is complete

Installing the blower wiring is really common sense. Thread the wires throught the wiring compartment on the assembly, and what I'm doing here is simply rotating the blower assembly around the existing conduit, to thread the fitting back into the blower.

That completed, I insert the pvc fitting into the base of the blower. It's a friction fit, and gets tighter as more pressure is exerted. If possible, I like to drill a self-tapping screw into the black blower fitting, through the PVC piping. This ensures that the blower won't 'blow itself off', of the pipe. DO NOT GLUE THIS FITTING!

Using a special pvc cement called PEVICOL, I plumb the old flex pvc pipe into the new blower tee. Never use regular PVC cement to do this! YOU WILL cause a blower explosion, destroy the blower, and possibly cause a fire. If you don't have PEVICOL, then you can use 2 or three deck screws to secure the hose into the plumbing fitting, or, using standard PVC cement, wait at LEAST 48 hours prior to energizing the blower! Be sure power remains disconnected for the duration of this... and DO NOT test the blower until after the 48 hours has passed! Otherwise you will destroy your blower using standard PVC cement!

Finish up the project now by reconnecting the three wires the same way they were removed. I also mount the wooden base using galvanized hanging strap material and galvanized deck screws as shown.

With the cover re-installed, I test the blower for about 3 seconds to ensure that it works properly, then let it sit for at least 8 hours to allow all of the silicone sealant to cure. Testing any longer than a few seconds will cause the sealant to be pushed out of the joints, requiring disassembly and re-sealing of the blown out joints.