Amana AFB2534DEW unit. Freezer works fine. Fridge is warm and does not respond to cooling level changes. Frost covered back of freezer wall which I removed. I also cleaned the coils under the unit. The weather here has been very warm and humid for nearly a week now and that's when problems started.

You could have one of two problems- 1) The defrost timer has failed OR 2) the defrost heater has failed.

Switch off fridge, open back panel check continuity of defrost heater. If it checks out OK you need to replace the defrost timer.

you have a defrost issue, while not familiar with hoover, normally there is a defrost timer, a defrost heater and a defrost thermostat, one of these three things are not operating. (may be more than one )

You have a sealed system problem. There is either a small leak or a restriction somewhere in the tubing. This isn't something you could've caused so don't worry about that. Unfortunately this isn't something you can fix yourself either. You require a certified refrigeration technician to fix this problem.

The cold from the freezer is piped up to the refrigerator and if that tube gets clogged with frost or ice it will not be able to blow to the cold air into the refrigerator area. I took everything out, unpluged the unit for about 6 hours, till all the frost from the freezer was gone, wiped up all moisture and turn it back on. It worked!

Normal 0 MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} Your evaporator coils frost up in normal use and every eight hours or so the entire unit shuts down and the defrost heater comes on to melt the frost. This cycle last about 20 minutes. The melted frost drips into a drain pan and through a drain tube to the drain tray under the freezer/refrigerator where it's evaporated by the condenser fan.

Your drain tube may be stopped up with ice at the upper end because it drains too slow because it's stopped up at the lower end in the evaporator pan under the unit at the floor. It can get dust and mold in it. Once you get the ice out at the top a little pressure with a turkey baster will usually clear it out. Flushing it out with hot water and clorox may help.
Make sure it drains quick enough to prevent refreezing. . The drain should be located below the evaporator coils on the lower back of the freezer.
Take a bare copper wire and wrap it around a fin near the heater and put the other end a few inches down the drain. The heat convection may prevent it from freezing.