Replacing A/C

[Lic0rice]

I need to replace our Dometic Quick Cool 15k a/c unit. Hoping to do the work myself. Has anyone here tackled a similar project or any experts in the house? Will greatly appreciate any suggestions, precautions, insight.

Thanks

[chuckster57]

Other than lifting the new unit onto the roof and getting the old unit off the roof, it should be a breeze.

Take the inside cover off. You will see a control box with wires connected by spade connectors that should be labeled.

Remove the control box from the A/C unit, unplug the 120V harness from the control box.

There will be 4 long bolts that hold the unit to the roof, through the interior plate, in the corners. Take them out and the unit should lift off.

Normally there is a foam gasket attached to the unit, just set the new unit in place and line up the 4 bolts. Screw them tight to get a good seal and reattach the control box. Plug the 120V harness back into the control box and your good to go. Put the inner cover back on and turn it on.

[Pull Toy]

All of the above, but unplug shore power, for that extra level of safety.

[Lic0rice]

Originally Posted by chuckster57

Other than lifting the new unit onto the roof and getting the old unit off the roof, it should be a breeze.

Take the inside cover off. You will see a control box with wires connected by spade connectors that should be labeled.

Remove the control box from the A/C unit, unplug the 120V harness from the control box.

There will be 4 long bolts that hold the unit to the roof, through the interior plate, in the corners. Take them out and the unit should lift off.

Normally there is a foam gasket attached to the unit, just set the new unit in place and line up the 4 bolts. Screw them tight to get a good seal and reattach the control box. Plug the 120V harness back into the control box and your good to go. Put the inner cover back on and turn it on.

Thanks for the quick reply!!

That sounds TOO easy!!
My two primary concerns.
- should a new Dometic unit fit the existing hole?
- will the control plug from a 10 yo unit fit the new plug?

Thanks again!!

[Tom N OH]

I have used both a drywall sheet lifter with a small piece of plywood on it & a tractor front end loader to lift A/C units to/from RV roofs.

[chuckster57]

Yes it should fit the hole.

Yes the new unit should plug into the control box as long as it's the same brand.

[Lic0rice]

Thanks guys!!

[Larry1013]

I replaced my A/C unit last year. Like many, worried about how to lift it off. I finally said to heck with it and went for the change out.

I have one of the 12ft tall metal prefab sheds/garage. I drilled a hole for an eye bolt in one of the roof arch. I then wrapped one of the ratchet tie downs around the old A/C and then used a come-along to lift the A/C unit. With A/C hanging, I pulled the trailer out from under the shed/garage. Ratcheted down the old unit and ratcheted up the new unit, backed the trailer back under the hanging new A/C. Lowered the A/C on the roof, centered it over the hole, snugged the unit down, removed the ratchet tie down from new A/C and come-along from the eye bolt.

Took about an hour to complete the change after countless hours/weeks of worry and trying to figure out a way of lifting the old and new A/C onto the roof.

Here is a photo of the arch supports over the trailer.



different angle of the shed/garage

[notanlines]

I helped our neighbor replace a similar unit a couple years ago. Shipping weight was 85 pounds I believe. We leaned a 24' aluminum ladder against the side of the trailer, tied a rope around the box and I pulled from the roof and he pushed it up the ladder. Honestly, it could not have been easier. He did all the work on the roof after that and I kind of guided him from inside the trailer. Want me to tell you about how we very gently eased the old one down to the ground? Good, because we simply threw it on down and the crash could be heard for miles. Okay, then all around the neighborhood.

[mfifield01]

I helped my friend replace his on his Puma 2 years ago. With 2 people it didn't seem that difficult. Both of us lifted it to the top of a ladder. I held it the ladder and he got on roof. He grabbed it from the roof and I pushed it up.