The freezer on my Amana ARB1917CB keeps frosting over; the fridge no longer cools. The advice given on most forums for this siutation is to "test the defrost timer by turning the screw with a screwdriver," etc. etc. (generally the same piece of advice cut-and-pasted into any number of forums), but with no indication of how to access this defrost timer on the ARB1917, or how exactly you're supposed to monkey with it while the fridge is on if you have to disassemble the fridge to get to the danged thing. I'd like to know EXACTLY where the defrost timer is an an Amana ARB1917 bottom-freezer fridge. Solutions like "it might be in the freezer behind a cover plate, or behind the front kickplate, or in the top of the refrigerator, or part of the compressor assembly" are of no real help.

https://www.ukwhitegoods.co.uk/forums/forum/public-support-forums/help-and-support/fridge-and-freezer-forum/83717-nextra-frost-free-freezer-hnu271-affl-no-longer-freezing

Is evaporator fan in freezer running? Is there any frost build up on inside back freezer wall?

If there is no cooling at all on the fridge section but the freezer works then it is confirmed that the compressor and gas pressure is OK. Now shut off the fridge and leave it powered off while you clean and check the evaporator for frost. If frost is seen it is a good indication as the compressor is working with sufficient gas within.
Now after about 6 hours plug in the fridge to start. Observe cooling to happen in about one hour and ice to from under three hours.
Earlier make sure that the thermostat was set to normal mode for freezer and fridge.
However if ice forms in the freezer then observe the fridge for about 24 hours for cooling to continue and the fridge to cut off . If not the auto defrost timer, or the thermostat must be checked. Frost formation without defrosting could block the air flow and so shut the air passage to the fridge. Also the blower fan must work and if this is not working then the fan can be faulty. Also a fault on the control unit is a suspect to non functioning of any one of these components.
If defrost timer works but frost keeps forming check while the compressor shuts if the heaters are working, check continuity of the heaters.
So try this test using a multi-meter on the defrost timer and the thermostat and make your observations so that we come to the solution.

Please check the link below for tips to remove the panels/parts: http://www.espares.co.uk/advice/fridges-and-freezers/a/2

If there is no cooling at all on the fridge section but the freezer works then it is confirmed that the compressor and gas pressure is OK. But if the freezer also gets warmer it can be failure of the auto defrost making the vents choked. Now shut off the fridge and leave it powered off while you clean and check the evaporator for frost. If frost is seen it is a good indication as the compressor is working with sufficient gas within.
Now after about 6 hours plug in the fridge to start. Observe cooling to happen in about one hour and ice to from under three hours.
Earlier make sure that the thermostat was set to normal mode for freezer and fridge.
However if ice forms in the freezer then observe the fridge for about 24 hours for cooling to continue and the fridge to cut off . If not the auto defrost timer, or the thermostat must be checked. Frost formation without defrosting could block the air flow and so shut the air passage to the fridge. Also the blower fan must work and if this is not working then the fan can be faulty. Also a fault on the control unit is a suspect to non functioning of any one of these components.
If defrost timer works but frost keeps forming check while the compressor shuts if the heaters are working, check continuity of the heaters.
So try this test using a multi-meter on the defrost timer and the thermostat and make your observations so that we come to the solution.

Please check the link below for tips to remove the panels/parts:

http://www.espares.co.uk/advice/fridges-and-freezers/a/2

Hi,

Check out these tips...they can help you figure out what is going wrong withyour refrigerator and why it is not cooling

Refrigeratornot Cooling or Fridge not Cooling

How to Defrost Refrigerator DefrostTimer Problem

WaterRunning in refrigerator from Freezer

Refrigeratoror Freezer not Cooling or Getting Cold
heatman101

if there is frost build up on rear wall of freezer section the unit is not going through defrost cycle which builds up frost on evaporator and restricts cold air flow to the fresh food section. one of three things are bad. defrost heater, defrost thermostat or defrost timer. if no frost on rear wall you might be low of freon.

Hi,
Check out these tips...they can help you figure out whats going wrong...

Refrigerator not Cooling or Fridge not Cooling
http://www.fixya.com/support/r3662945-refrigerator_not_cooling_or_fridge_not

How to Defrost Refrigerator Defrost Timer Problem
http://www.fixya.com/support/r3771673-defrost_refrigerator_defrost_timer


Water Running in Refrigerator from Freezer
http://www.fixya.com/support/r3780310-water_running_in_refrigerator_from

heatman101

Check the damper in the top back of the fresh food section. make sure that it is open and air is coming through it.

freezer side is working good but cooling side is not cool

Same problem here with an Amana refrigerator with the freezer on the bottom. I removed the back panels and vacuumed dust and cat hair out. The back panel in the freezer was frosted over with ice on the bottom. I removed the shelves and food and used a hairdryer to loosen the panel. The ice maker made it harder to remove the plastic panel so I pulled it back and saw the cooling fins frozen solid. I used the hairdryer to melt the ice and a shop vacuum to collect the water. It works like new again.