Compressor vs capacitor failure

A Jurong West customer was advised to replace their outdoor compressor. The unit wasn't cooling, and the contractor said the compressor was dead. Before committing to major work, they wanted confirmation. What we found was different. If you were told to replace a compressor directly, get a WhatsApp second opinion first.

What the customer told us

  • Unit: 9-year-old Panasonic split system, living room
  • Symptom: Not cold, outdoor unit fan spinning but compressor not running
  • History: Worked fine until last week, now won't cool at all
  • Previous contractor's diagnosis: 'Compressor motor burnt out - needs replacement'
  • Customer concern: 'Unit is old, and this sounds like major work. I want to be sure before spending.'

What we assessed

A non-running compressor can be caused by the compressor itself, or by components that control it. Before assuming the compressor is dead, we test what's actually failed.

We found it:

  • Power was reaching the compressor
  • Compressor motor checks looked normal
  • Start component performance was below expected range
  • Compressor was humming but not starting, a common start-component pattern

Why this happened

Compressors need a capacitor to provide extra starting power - like a jump-start battery. When the capacitor degrades (common after 7-10 years), it can't deliver enough boost. The compressor tries to start, hums, but can't overcome the initial resistance. This looks like a dead compressor from the outside, but the compressor itself is fine. It just needs the capacitor replaced.

Full compressor replacement

INITIAL RECOMMENDATION

Compressor replacement

Start component replacement

ACTUAL REPAIR PATH

Targeted repair

Major to targeted

SCOPE SHIFT

After verification steps

4 months

RUNNING SINCE FIX

Compressor still original

What we advised

Replace the capacitor first. If the compressor starts and runs normally after, the problem is solved. If the compressor still won't start after capacitor replacement, then we investigate the compressor itself. Rule out the smaller, testable fix before committing to a major replacement.

Band-aid approach

Approach

Replace compressor

Timeline

3-5 days + parts ordering

Cost

High-cost major repair

Permanent fix

Approach

Test & replace capacitor

Timeline

Fixed same day

Cost

Lower-cost targeted repair after testing

What happened

Customer approved the start-component replacement. Compressor started normally, ran smoothly, and cooling returned. The customer avoided unnecessary major replacement. The unit is still running fine 4 months later.

Week 1

Unit stopped cooling, outdoor compressor not starting

Week 1 (Day 3)

Previous contractor recommended compressor replacement

Week 2 (Day 1)

Customer contacted Snowflake for second opinion

Week 2 (Day 1, 2 hours later)

Snowflake assessment: Tested compressor motor (fine), tested capacitor (failed)

Week 2 (Day 2)

Replaced capacitor, compressor started normally, cooling restored

Present

4 months later - compressor still running, zero issues

What this shows

Why assessment matters

A compressor that hums but won't start usually means a failed capacitor, not a failed compressor. Without step-by-step checks, recommendations can jump too quickly to full replacement. The previous contractor saw 'compressor not running' and jumped to 'compressor replacement.' They moved to a major explanation before ruling out smaller causes.

What we do differently

We test components in order of likelihood and cost. We do not recommend major replacement until smaller, testable causes are ruled out. Assessment means testing what actually failed, not guessing based on symptoms alone. If you have a major quote, send it on WhatsApp and we will help you pressure-test the scope.

Having a similar issue?

Tell us what's happening. We'll assess your unit and give you one clear recommendation.

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