Costs · Kirkland
Defrost Heater, Thermostat or Sensor: Cost
A defrost system is the heater that melts frost off the freezer coil, plus the parts that start and stop it. When one of them fails, the repair falls in the $300–$680 band and the figure is fixed before work starts. Sub-Zero Repair Kirkland, (425) 699-2400, 8 am to 8 pm daily.
- Term
- Defrost system
- Band
- $300–$680Defrost
- Tell
- Frost gathers on the rear wall over the vent and is back within days of being scraped off.
| Band | Covers | Range |
|---|---|---|
| Defrost heater, thermostat or sensor | Heater, terminating thermostat or temperature sensor on the freezer coil | $300–$680 |
Service call The $89 visit covers coming out and diagnosing the fault in full, and all $89 comes back to you as a credit on any repair you go ahead with.
What the band covers
A frost-free freezer has to warm its own coil every so often. The heater does the melting, and a thermostat or sensor tells the control when the coil is clear so the heater can stop. If you have ever heard a crackle or a sizzle from behind the freezer wall, that is the normal sound of a defrost: the frost letting go and the water running off to the drain pan.
A failure anywhere in that chain gives the same picture. The coil ices over a little more with each cycle until air can no longer pass through it, and the freezer that was cold last month starts to soften. On a tall unit such as the BI-36F all-freezer column the coil sits behind a panel inside the compartment, so reaching it means emptying the freezer and letting the ice go first.
What moves the figure inside the band
Which of the three parts failed matters most — a heater and a sensor are not the same part, and they are sometimes replaced together because the work to reach them is the same. Then there is the thaw: a coil that is solid with ice has to melt out fully before the panel can come off, and rushing it with heat damages the fins. A drain that has frozen along with the coil adds a little more time. The band on this page covers all of that, and the figure for your unit is agreed once the part is known.
When it is not the defrost system
Frost near the door or along a drawer seal is usually air getting in, not heat failing to arrive, and that is a cheaper repair — the page on frost buildup repair costs sets those causes side by side. If you are not sure which you have, a freezer repair visit starts with the diagnosis, and the $89 comes off the repair when you approve it.
Check these before you call
- 01
Take the top basket out and look at the rear wall. A crust over the vent that returns within days points at the defrost side.
- 02
Close the door or drawer on a strip of paper at several points round the seal. Where it slides out with no drag, room air is getting in.
- 03
Look at the condenser grille, at the top or at the toe-kick depending on the model, for a mat of dust or lint.
Still wrong after that? Sub-Zero Repair Kirkland, (425) 699-2400 — visits eight till eight, every day.
Field log
Priced, fixed, signed off.
What Kirkland owners wrote after the figure was agreed and the work was done.
5.0 / 5524 reviews
Panel-ready unit wedged into a tight condo kitchen with an inch of clearance either side. He walked it out on a dolly, replaced the control board, and put every panel back without marking the maple.
Corinne A.Totem Lake
Bin filling with one fused block instead of cubes. He said that usually points at overflow rather than the maker, and the water valve was indeed seeping past. New valve, bin stripped and cleaned, advice on travel.
Marcus E.Juanita
Thermoelectric unit in a nineties remodel that nobody else would look at. He found the cooling module tired but the cabinet sound, gave us the honest choice, and rebuilt what could be saved. Holding 55°F three weeks on.
Beatriz N.Houghton
Next step
Say what the unit is doing. The band comes before the bill.
Have the model number from the rating plate and a line on what the unit is doing. The visit is $89, the fault is named and priced inside its published band, and nothing is replaced until you agree the figure.