fridge not cold ...

I'm diagnosing a tenant's fridge problem. The lower compartment doesn't get cold at all, the freezer works like a charm. There's air coming out of the freezer's fan outlet, but nothing down below. We've defrosted, I've chipped ice away from the lower compartment's fan baffle, and I'm assuming at this point that I'll have to open the wall up to really clear out the ductwork.
Roper RT18DKXXL00 / 18ATR92
It's 12 years old, so not worth a great deal of repair expense. If clearing the duct fails, I'm thinking I need to test the frost-free components based on the advice at http://www.applianceaid.com/frig_notcold.html
Am I proceeding the right way? Any other advice? I'm handy enough with tools but multimeter testing is sort of a vague area to me.
Other symptoms are no dripping from the back drains, and one seems to be rusting up at the junction between metal and plastic. Could that be the ultimate cause?
Compressor and condenser seem OK from what I can tell, but then, I'm not 100% sure what to check.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sounds like defrost failure. A refrig guy oughta be able to fix that. As long as the compressor is working (which yours is) the fridge is fixable.
--

Christopher A. Young
Learn more about Jesus
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This is Turtle.
Yes Defrost terminator , Defrost Elements, and Defrost Timer are in line to look at.
Now you can have a defrost drain can stopped up and water will freeze in the air duct between the top and the bottom. This is something to look at as to drain stopped up and cause water to freeze up air channels under the freeze compartment floor. Totally defrost it and let it sit over nite and then clean out drain pipe going from freezer coil to pan under the units on right side.
TURTLE
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.