Need appliance parts? Call 877-803-7957 now or use the parts search box:

Parts Search

Learn appliance repair at online the Master Samurai Tech Academy.  Learn more.  Earn more.

FAQs | Repair Videos | Academy | Newsletter | Podcast | Contact

danblum

Sub-Zero 550 freezer

6 posts in this topic

I recently inherited and older Sub-Zero 550 bottom-freezer refrigerator and after a little tinkering and a ton of cleaning, it is working pretty well. The only problem now is that the freezer temperature stays at zero degrees Fahrenheit, regardless of the dial setting of the freezer control. It measures zero degrees on "10" and zero degrees on "1". I am also measuring the current draw and finding that the freezer compressor runs almost continuously (except during defrost cycles). 

The only other unusual circumstance is that I don't have any water hooked up to the ice maker yet. 

Most people would probably be happy with a freezer that stays at zero degrees, but I know it is supposed to be adjustable.

Share this post


Link to post
Share on other sites

Need appliance parts? Call 877-803-7957 now!

[user=60886]danblum[/user] wrote:

... that the freezer compressor runs almost continuously (except during defrost cycles)...

may be a sign of a (SZ common) sealed system leak ...

take a look at the frost pattern on the Freezer Evaporator Coils .. post picture ?

 

Share this post


Link to post
Share on other sites

Frost pattern appears to be pretty uniform The first picture is the frost pattern on the ice maker side, looking straight up from the floor of the freezer. The second picture is the same coil on the defrost drain side. I see a light frost build up on all the copper u-tubes.

post-60886-129045115289_thumb.jpg

Share this post


Link to post
Share on other sites

evenly frosted is good, may be a little lightly ...

And the Freezer Compressor runs almost continuously ?

I'm not sure what the problem could be .. maybe someone else ..

SubZero 500 series service manual link PM'd ..

Share this post


Link to post
Share on other sites

Make sure the thermostat knob is actually turning the thermostat...knob coulb be broken...also make sure your door gaskets aren't leaking.

In your second picture on the left side your defrost heater is melting some plastic....you may want to address that.

Share this post


Link to post
Share on other sites

Frost pattern looks good. The contacts of the freezer thermostat may be welded together or it's just out of calibration. Not uncommon with the older bourdon tube thermostats.

Share this post


Link to post
Share on other sites