We tag every fault our technicians find into a database. Here's what 722 of them show about which parts fail, why they fail, and how much of it could have been avoided. Updated monthly.
Share of all 722 diagnosed faults, by the component the technician identified. Counts are in parentheses.
"All other components" combines 11 smaller categories, such as tub shell / liner, other, valves & unions, flow / pressure switch, refrigerant system, condenser fan. None of them individually exceeds 2.2%.
135 faults (18.7%) left the unit completely down. The circulation pump stands out here. When a pump stops, nothing else matters: no flow means no filtration and no cooling, and many units will lock out the chiller to protect it.
Of the 722 faults, 303 had a root cause the technician could document on site. The chart covers only those 303.
419 faults (58.0%) have no documented root cause, and we chose not to guess. Two things drive that number:
As a result, the known-cause breakdown above is the more useful view, though it likely understates wear and manufacturing defects, because those are concentrated in the warranty work.
Our technicians flag each fault as preventable or not. 228 of 722 (31.6%) were rated preventable.
Some failures are almost entirely about upkeep. Others are mostly bad luck or age.
The pump figure is worth a second look. Only 19% of pump faults were directly rated preventable, but clogged filters and closed valves that starve a pump show up repeatedly in the notes as contributing factors. Clean filters are cheap insurance for the most expensive-to-lose part of the water path.
548 faults came from residential units and 86 from commercial installs such as gyms, recovery studios and training facilities. The other 88 weren't tagged with a setting.
| Measure | Residential (n=548) | Commercial (n=86) |
|---|---|---|
| Faults rated preventable | 31.0% (170) | 45.3% (39) |
| Major or unit-down severity | 39.2% (215) | 46.5% (40) |
| Skipped maintenance, share of known causes | 27.9% (65 of 233) | 41.3% (19 of 46) |
| Most common failing component | Circulation pump, 18.4% | Filter housing / canister, 14.0% |
| Chiller coils & airflow faults | 2.4% (13) | 10.5% (9) |
Commercial units run many more cycles a day, carry heavier organic load from sweat and skin care products, and often sit in tight equipment spaces. Some commercial sites logged the same issue across several units at once, which pushes these percentages up. With 86 commercial faults, treat the comparison as directional rather than precise.
These recur in technician notes regardless of who made the unit. Counts are the number of notes that describe each issue.
We've repeatedly seen the same chain: the filter clogs, flow drops, the pump strains and fails, and the chiller stops cooling because no water is reaching it. Several notes describe filters that had never been changed since install, including one left in place for about 43 months.
7 notes cite extension cords as a cause or contributor, including a dead compressor, blown fuses from voltage drop, and a sparking cord. 3 more describe plugs melted into or alongside power strips. Plunges need a dedicated, properly located GFCI outlet.
About a dozen notes describe trapped air: filter housings closed without being pre-filled, leaking unions or intake lines pulling in air, and new installs that wouldn't prime. Most cleared on site once the air was bled out.
9 notes tie damage to too much chlorine: corroded stainless liners, failed displays and boards, and internal chiller corrosion. Pool-style tablet floaters were a repeat offender. A plunge holds a fraction of a pool's water, so pool dosing habits overshoot badly.
10 notes describe mineral scale: a pump seized with calcium, heat exchangers needing descaling, and lines restricted even after a new pump went in. In hard-water areas, a periodic descale belongs on the maintenance list.
16 notes describe biofilm or algae. It's often dislodged from the jets the moment a new pump starts, which is why a pump swap on a neglected unit usually needs a full drain, line flush and sanitize.
9 notes involve ice or freezing. Some were chillers that ran without water moving through them and iced internally, and others were units left outdoors through a freeze. Both can crack fittings or damage the sealed system.
Small but avoidable: 3 filter housings were cracked or leaking from an overtightened cap, and 3 units had a closed or partly closed valve starving the pump. Hand-tight is tight enough.
Mapped to what the data shows. None of these require tools beyond what came with your plunge. Our care guide has the full routine.
Follow your manufacturer's interval and replace sooner if the pleats stay discolored after rinsing. Clean the in-tub pre-filter or hair catch at the same time.
Targets: filter cartridge faults (86% preventable), pump starvationAfter any filter change, fill the housing with water, hand-tighten the cap, and listen for the pump to run smooth before you walk away.
Targets: airlocks, flow errors, cracked housingsUse the sanitizer your manufacturer specifies at plunge-volume doses. Never use pool tablet floaters. Test regularly, and drain and refill on schedule.
Targets: water-quality faults (97% preventable), corrosion, board damageKeep vents clear of towels, walls and stored gear, keep dust off the coils, and avoid tightly enclosed cabinets without exhaust. Commercial units need coil cleaning on a set schedule.
Targets: coil and airflow faults (79% preventable)Plug the unit straight into a properly installed GFCI outlet placed a safe distance from the water. If it trips twice, stop resetting it and call.
Targets: power faults, blown fuses, compressor damageIf you see white crust at the waterline or on the chiller, ask about a descale during your next service. Scale quietly chokes pumps and heat exchangers.
Targets: seized pumps, restricted heat exchangersThe Cold Standard, "What Breaks on Cold Plunges: Field Data Report, October 2026," https://coldstandardservice.com/cold-plunge-failure-report/2026-10
In our data, the circulation pump: 17.7% of 722 diagnosed faults, and 40% of the faults that left a unit completely down. Filter housing / canister (12.3%) and power supply, cords, gfci & fuses (11.1%) are next.
Our technicians rated 31.6% of faults (228 of 722) as preventable through routine maintenance, correct installation, or correct day-to-day use. Among faults with a documented root cause, skipped or overdue maintenance was the single most common cause at 29.7%.
Compressor and whole-chiller failures were 7.2% of faults, and the entire cooling side (compressor, coils and airflow, refrigerant, condenser fan) was 13.0%. Many units that seem to have a chiller problem actually have a water-flow problem, since pumps, filters, plumbing, valves and flow switches made up 48.8% of faults.
In our data, yes: 45.3% of commercial faults were rated preventable versus 31.0% for residential, and skipped maintenance accounted for 41.3% of commercial faults with a known cause. The commercial sample is smaller (86 faults), so treat it as directional.
Every month. Each edition is archived at its own address so changes over time stay visible — this is the October 2026 edition, covering every fault in our database for visits through October 5, 2026.
A maintenance plan catches clogged filters, chemistry drift, dusty coils and loose connections before they become a dead pump or a warranty claim. Every visit ends with a photo report.
Tell us about your unit. We'll reply with next steps, usually the same day.