Older All-Freezers (501F / 601F): the Freezer Compartment Only

Two generations, one job

Both are freezer from top to bottom, with the condenser behind a louvered grille above the door. What separates them, freezer-side, is how they decide when to defrost.

On the 501F the freezer defrost is run by a timer. Sub-Zero’s guide describes the crackle and sizzle you may hear as the defrost element clears frost from the freezer coil and the water runs down to a pan. On the 601F the freezer uses what Sub-Zero calls Adaptive Defrost, which defrosts only as needed. Either way, if a heater, the switch that ends the cycle or the part that times it gives out, the coil ices over and the cabinet warms. Frost that keeps coming back is covered in the note on frost that returns after every defrost.

The 600 Series guide also notes a fan behind the grille that cools the compressor area; a dusty condenser makes that compartment run hot and long, which is hard on an old compressor.

When the sealed system is the question

A gasket or defrost part is ordinary work, priced in its band. The harder call is the refrigerant loop. When the compressor has stopped or the system has lost its charge, the repair is a large figure spent on an old cabinet, and it deserves the comparison set out under repair against replacement. The work itself is priced on the compressor replacement cost page.

The decision is the owner’s; the visit supplies the diagnosis and a stated figure first.

What an owner can check

Confirm the freezer setting has not been turned: the dial on a 501F, or the digital reading on a 601F. Close a strip of paper in the door along each side and feel for drag on the way out. Look at the grille for dust and anything blocking it. Parts for units this age may take longer to source, so a Kirkland owner is better calling early than waiting for the food to soften.

Asked about this unit

How do I tell a 501F from a 601F?

Look at the control. The 500 Series owner's guide shows a lighted dial that you turn to set the freezer. The 601F has an electronic Control Center, mounted in the freezer compartment on this model, with one pair of warmer and colder pads and a display. The model and serial plate confirms it. Sub-Zero Repair Kirkland, (425) 699-2400.

What temperature should a 601F hold?

The 600 Series guide says the freezer leaves the factory set at 0°F and can be adjusted from five below to five above. The same Control Center flashes a SERVICE light for a temperature or ice maker problem, and also when the condenser needs cleaning, so a clean condenser is the first thing to check.

How often should the condenser on these older freezers be cleaned?

The original 500 and 600 Series guides both say every three to six months. Sub-Zero's current help page for those series gives six to twelve months. On a cabinet this age, the shorter interval is the safer habit. Power off first, wear gloves, and brush and vacuum along the fins, never across them.