Rooftop ac repair

[mike brez]

Ok both my rooftops are not working. Dometic Duro Therms.
Took covers off and installed peircing service valves. Both had no freon. Both had pin holes in capillary tube in same place apparently rubbing issue. Cut sheet metal to access. Put a drop of braze on one and cut one out and sleeved with a peice of 1/4 inch tube and brazed. Pulled a vacuum on both and filled both with 24.5 oz of r22.
Wasn't very warm but shot the rear plastic ac grate with ir gun 67* fired up generator turned rear ac an feels cool 15 min shot plastic ac grate again in same spot 48*
Shut down rear and started front. Fan comes on but compressor keeps on trying to start every minute or so and cuts out. Removed wires from compressor and all have continuity. Switched all capacitors and compressor over load switch from working rear to front and no change. I guess compressor is locked up. Was thinking of trying a hard start kit but not sure it would work. Was thinking about trying to find a compressor but a quick search showed nothing. Gotta hop back on roof and get numbers off it. Here's a few pics.

[Smitty77]

Mike - My money's on you!

No doubt, you'll MacGyver this until solved...

Nice job on the repair of the tubes - most tech's would have called the units toast...

Any chance you have a failing capacitor? Perhaps swap the capacitors from working AC to non starting unit - who know, may get lucky!

Best,
Smitty

[mike brez]

Originally Posted by Smitty77

Mike - My money's on you!

No doubt, you'll MacGyver this until solved...

Nice job on the repair of the tubes - most tech's would have called the units toast...

Any chance you have a failing capacitor? Perhaps swap the capacitors from working AC to non starting unit - who know, may get lucky!

Best,
Smitty

Yes thanks I tried that it's in my original post.
I may just go and buy two new ac's the boards and thermostate.
If we go away and these quit my better half to put it lightly won't be too happy with me.

[Dom]

A hard start kit is worth a try. I used to work on those units and found lots of failures with the lay down compressor. One hint, if you are brazing anyway, why not braze in a 1/8 in schrader valve. Less change of a leak down the road.

[Burfman]

Agree with Dom. I did exactly that many yeas back, put in the schrader valves and did a hard start kit on the rear unit. Still working today. I had to laugh at your repair on the cap tube. I did that many times on refers and window A/C units instead of replacing them.

Kudos to your mechanicing abilities...

[Dom]

Actually a pretty good repair on cap tube. Looks professional

[Burfman]

agree....not laughing at the repair but to the fact Mike is doing what I did some 57 years ago when I was an appliance tech for..drum roll please......"Montgomery Wards" in northern California..

[mike brez]

Duplicate

[mike brez]

Originally Posted by Dom

A hard start kit is worth a try. I used to work on those units and found lots of failures with the lay down compressor. One hint, if you are brazing anyway, why not braze in a 1/8 in schrader valve. Less change of a leak down the road.

Yea I know all about the peircing valve that's all I had. I installed one one my old rv and never had a issue with it for years and was still working when I sold it.
I was thinking of trying a hard start kit as I said n my original post.
Need to think about what direction I want to go. I'm seriously thinking about changing them both out. The only thing stopping me is the $2700.00 for them.

[Roy1]

That is the way I always fixed cap tubes that wore thru from rubbing. Piercing valves is a temporary repair at best they always leaked in time. Best to sweat in a Schrader valve. If your unit has a start capacitor a hard start kit won’t help that is the purpose of the start capacitor. You might have a bad start relay? You could swap that with your working unit . Make sure you are getting the full 120 volts when the compressor is trying to start .

[Dom]

I never liked the mechanical start relays as they are voltage sensitive. If you are starting out with low voltage, the pickup voltage is also less. I think nowadays most hard start kits use solid state relays

[mike brez]

Ok I'm done. Tried beating it with a rubber mallet while trying to start nothing.
Went to the ac supply house and picked up a hard start kit,compressor still won't come on.

[mike brez]

Just ordered two new Penquin 15k with heat pumps yesterday. Back one is working good but rather have both the same.
If anyone in the area needs a ac or some parts it's yours. The front one I'm just going to throw off the roof,the rear one I will be a little more carefull with.

[mike brez]

Originally Posted by mike brez

Just ordered two new Penquin 15k with heat pumps yesterday. Back one is working good but rather have both the same.
If anyone in the area needs a ac or some parts it's yours. The front one I'm just going to throw off the roof,the rear one I will be a little more carefull with.

Also have the 4 button thermostate if needed.