Oh boy. the ammonia smell is not a good thing. The gas burner area is a more common place for the cooling coil to fail, but it is not the only one.
Your older fridge may look a little different in the burner area. If you take the burner shield off and can see the burner directly, then look and sniff in that area.
The burner with the shield on
Yellow residue near burner area 1
Yellow residue near burner area 2
If your burner area does not smell or have any kind of yellow residue, keep a good lookout for it. If yours sprung a leak up in the freezer area, it is still a problem just you may not see it as easy. But the smell is a dead give away.
Careful on leaving it run for hours on end if there is a leak. The leak will prevent the unit from cooling correctly and overheat the boiler area creating a fire hazard.
After 1 to 2 hours of running, there should be a slight change cooler in the freezer plate on the back wall of the freezer I would think. I have never tried this yet, but can if you need me too. If you can check the surface temp before you turn it on and then after it has been on with the door closed in between, you should see it dropping by some amount. Ideally use some kind of surface temperature thermometer if possible. Even a cooking thermometer if the graduations go down to room temperature. You can try your touch by hand if that is all you have.
If it has been on for 4 hours and there is no change in temp on that freezer plate, that is not a good sign. Check the burner area metal and the cooling tubes (pipes) before the burner area for heat also. If the pipes are getting warmer, then it is trying to cool something. If the pipes have not changed temp since started and the burner area is getting warmer after 2 to 4 hrs, that can also mean all the coolant or a good portion of the coolant leaked out.
Again, the smell is a true tell tale sign there is a leak somewhere. Trying to run the unit may expand the crack and the smell get worse. You may have just caught yours are it started to leak. Not all leaks go big at once.
Hope this helps and let us know what you find out.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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