01Temperature
Cold at the Bottom, Warm at the Top
Check these before you call anyone
- 01
Find the outlet the cold air leaves by and make sure nothing is parked against it. One flat box over that grille can cost the top shelf several degrees.
- 02
Pull the upper baskets out and look at how tightly they are packed. Air has to get round a load, not merely past the front of it.
- 03
Open the door and listen at once, before anything winds down. A fan that is silent, or that slows and picks up again, moves far less air than one running steadily.
- 04
Leave a thermometer on the top shelf overnight and a second at the bottom. A gap you can still measure in the morning is the fault; one that closes was just an open door.
If none of that is it, stop there — the next step needs a meter. Sub-Zero Repair Experts Los Angeles, (310) 496-3358.
Cold falls, and something has to lift it
Cold air is heavy. Left to itself it pools on the floor of the compartment while the top shelf drifts towards the room. The one thing preventing that is a fan behind the rear panel, pushing air off the coil across the full height of the box and drawing it back through a return lower down. Block either end of that loop, or slow the fan, and the box settles into layers.
Two causes that look identical
Overpacking and a tiring fan produce the same gradient. One of them is free to rule out: clear the vents, loosen the load, wait a night. If the layers survive that, the air is not moving on its own account, and the reason sits behind the panel — a motor losing speed, or a blade catching ice.
If it is not that
When the fan behind the rear panel is the part that has slowed, the work and the band are onthe evaporator fan motor page.
If the whole compartment is warm rather than only its top, the question is a different one andthe freezer box page answers it.
Deep ranch kitchens with tall columns show this pattern often, which is why it leadsthe Sherman Oaks page.
Follow-ups
Is a warmer top shelf normal in a freezer?
A degree or two is ordinary and nobody would notice it. A gap wide enough to leave bread soft at the top while the bottom basket is rock hard is not ordinary: it means air leaving the coil reaches one part of the compartment and not the other.
Will unloading the freezer fix it?
Sometimes, and that is worth knowing before anyone is paid to visit. Clear the vents, leave a hand's width round the load, and give it a night. If the gap is still there in the morning the fan or its duct is the reason — Sub-Zero Repair Experts Los Angeles, (310) 496-3358.
Sub-Zero Repair Experts Los Angeles works on Sub-Zero freezers across the east side and the south valley. (310) 496-3358 — answered 24/7, on-site 8:00 am – 8:00 pm, seven days, $89 for the visit and the diagnosis.