Ductless Mini-Split Repair in Berkeley & the East Bay
$79 diagnostic fee. All brands serviced. EPA 608 certified, factory-trained technicians. Written repair quote before any work begins. CSLB #1146520.
★★★★★
“I had a duct fan fail in a very heat sensitive wine cellar and Aarvaks came same day to diagnose issue. They ordered the part and picked it up the next day and everything was fixed within 48 hours. Personal service. Professional service. They know their stuff. They are prompt and reliable. Trustworthy.”
Repair Process
What Happens During a Ductless Mini-Split Diagnostic
The $79 diagnostic covers a full system inspection. Ductless mini-splits self-report faults through error codes — reading and interpreting those codes is the first step before any physical inspection begins.
- Error code retrieval — read fault codes from the indoor unit display and service history; most ductless mini-splits store the last several fault events accessible via remote control or service menu; the code identifies which component flagged a fault before we touch the system
- Visual inspection of indoor and outdoor units — coil condition, refrigerant line insulation, electrical connections, condensate drain pan condition, and all accessible components
- Refrigerant pressure check and flare fitting inspection — verify charge against manufacturer spec in the current operating mode; flare fittings at the indoor unit connection are the most common leak point on ductless mini-splits, particularly on systems that were improperly installed or disturbed during other work
- Reversing valve test — confirm the valve switches correctly between heating and cooling modes; a stuck reversing valve locks the system in one mode regardless of thermostat setting
- Defrost system check — verify defrost control board, defrost thermostat, and defrost cycle timing; defrost failure causes ice accumulation on the outdoor unit in winter and degraded heating output
- Electrical component testing — measure run and start capacitor microfarad rating, contactor condition, control board operation, and fuse continuity
- Communication wire inspection — test signal integrity between indoor and outdoor units; a damaged or loose communication wire triggers error codes and full system lockout without any refrigerant or mechanical fault
- Indoor unit inspection — blower wheel condition for mold or debris buildup, evaporator coil for ice or restriction, air filter condition; dirty blower wheels are a leading cause of reduced airflow, rattling noise, and poor performance on wall-mounted ductless mini-splits
- Condensate drain inspection — verify drain line flow and condensate pump operation where installed; a clogged drain causes water to overflow the indoor unit and drip from the wall
- Written repair recommendation with itemized pricing — no work begins without your approval
What We Fix
Common Ductless Mini-Split Repairs
Aarvaks technicians service all ductless mini-split brands — Carrier, Bosch, Mitsubishi, Daikin, Fujitsu, LG, Samsung, Lennox, and more. If it heats and cools your space without ductwork, we service it.
Refrigerant & Reversing Valve
Refrigerant leak detection and recharge, reversing valve replacement, TXV and metering device. Flare fittings at the indoor unit connection are the most common leak point on ductless mini-splits — adding refrigerant without locating and fixing the leak is not a repair. A stuck reversing valve leaves the system locked in heating or cooling mode only.
Electrical, Controls & Error Codes
Control board, communication wire, run and start capacitors, contactor, defrost control board, relay, and thermostat replacement. A failed communication wire between indoor and outdoor units generates error codes and system lockout — no refrigerant or mechanical fault required. We read the fault history and confirm root cause before ordering any part.
Indoor Unit & Drain System
Blower wheel cleaning and replacement, evaporator coil cleaning and repair, condensate drain clearing, condensate pump replacement, and indoor fan motor replacement. Ductless mini-split wall units accumulate mold and debris on the blower wheel faster than central systems — fouled wheels cause rattling noise, reduced airflow, and degraded heating and cooling performance.
Transparent Pricing
Ductless Mini-Split Repair Cost
The diagnostic fee covers the full inspection and written repair recommendation. Repair costs vary by component and labor required. We provide itemized pricing before any work begins — no surprises on the invoice.
$79
Residential diagnostic fee
Waived if we do the repair
$189
Commercial diagnostic fee
All commercial ductless mini-split brands
All Brands
Carrier, Mitsubishi, Bosch, Daikin
Fujitsu, LG, Samsung & more
Written itemized quote provided before any repair work begins. Diagnostic fee waived if we do the repair. Financing available on qualifying repairs.
Common Questions
Frequently Asked Questions
How much does ductless mini-split repair cost in Berkeley?
The $79 residential diagnostic covers the full system inspection and a written repair recommendation with itemized pricing. The total repair cost depends on the component — a capacitor or communication wire replacement costs significantly less than a reversing valve or compressor. You see the exact cost before approving any work. Call 510-848-5010 or book online to schedule a diagnostic.
My ductless mini-split is showing an error code — what does that mean?
Error codes identify which component reported a fault — the system is telling you what failed. Common codes indicate refrigerant pressure problems, communication faults between indoor and outdoor units, thermistor failure, or drain overflow. Note the code before calling or scheduling service; it’s displayed on the indoor unit and stored in the fault history. We read the fault history at the start of every diagnostic to confirm root cause before any physical inspection.
My ductless mini-split is running but not cooling — what could cause that?
The most common causes are low refrigerant from a flare fitting leak, a restricted evaporator coil, or a stuck reversing valve leaving the system in heating mode. A dirty blower wheel or clogged filter can also reduce airflow enough that the unit runs without cooling the room effectively. Adding refrigerant without locating the leak source is not a fix — the diagnostic identifies the root cause before any repair work begins.
Water is dripping from my ductless mini-split indoor unit — is that serious?
Yes — shut the system off. The indoor unit drain pan overflows when the condensate drain line is clogged or the condensate pump fails. Running the system with a blocked drain causes water to back up into the wall and ceiling. If the leak is reaching flooring or drywall, call immediately at 510-848-5010 for priority service. A drain clearing is a straightforward repair; water damage is not.
Can any HVAC technician repair my ductless mini-split, or does it have to be the brand’s installer?
Any licensed HVAC contractor can repair your ductless mini-split regardless of who installed it. You are never locked into the original installer. Aarvaks services all residential and commercial ductless mini-split brands — Carrier, Bosch, Mitsubishi, Daikin, Fujitsu, LG, Samsung, Lennox, and more. CSLB #1146520.
How do I know if my ductless mini-split needs repair or replacement?
If the repair cost approaches or exceeds half the cost of a comparable new system, replacement is usually the better investment — particularly on a system over 15 years old. A compressor failure on an aging unit is often the decision point. We give you both figures — repair cost and replacement cost — so you can decide without pressure. Ductless mini-split installation starts at $6,500 for a single-zone system.
Ductless Mini-Split Not Working?
$79 diagnostic. Written repair quote before any work begins. All brands serviced. Serving Berkeley and the East Bay since 1929.