Updated: May 13, 2026
Location and Projects
Address
378 S LEMON AVE, Walnut, CA, 91789
Use our bidding system to
request a quote
Steve Yi HVAC/Mechanical Contractor
Steve Yi, 378 S Lemon Ave, Walnut, CA (Employee: Steve Yi) holds a Warm Air Heating, Ventilating And Air Conditioning license and 1 other license according to the California license board.
Their BuildZoom score of 100 ranks in the top 13% of 336,931 California licensed contractors.
Their license was verified as active when we last checked. If you are thinking of hiring Steve Yi, we recommend double-checking their license status with the license board and using our project planner to get competitive quotes.
Steve Yi Contact Information
Phone Number: (909) 816-0016
Edit
Address: 378 S LEMON AVE, Walnut, CA 91789
Edit
Do you work for this business? Unlock this free profile to update company info and see who's viewing your profile.
Steve Yi Walnut
Quality
100
87th percentile
Pro tip:
We generally recommend hiring a contractor with a score higher than 95.
Steve Yi has a BuildZoom score of 100, which places them above 87% of 336,931 contractors in California.
Activity
|
3 projects
|
2025 |
|
1 project
|
2023 |
Our building permit records indicate that Steve Yi has worked on at least
4.0 projects over the past 3 years.
This is an overview of this contractor's activity. Click here to access our complete licensing and building permit database.
This is an overview of this contractor's activity. Click here to access our complete licensing and building permit database.
Pricing
|
1 project
|
$250k-$500k |
|
1 project
|
$500k-$1mil |
Pro tip:
For more details about their pricing, check out their recent activity to see how much they have charged for different types of work.
This is a sample of this contractor's permits. Click here to access their complete permit history.
Wacr-01: residence. air conditioning and/or furnace changeout | wacr-02: [new/replace] ducts/registers | additional details: -
Valuation:
N/A
Permit #:
00952391-WACR
Status:
final
Fee:
N/A
Permit Type:
N/A
Building Type:
N/A
(e-plan) roof mounted photovoltaic system w battery back up system
Valuation:
N/A
Permit #:
00913250-RRA
Status:
final
Fee:
N/A
Permit Type:
N/A
Building Type:
N/A
Installing 3 14kbtu direct heater on the wall
Valuation:
N/A
Permit #:
20044-10000-02077
Status:
final
Fee:
N/A
Permit Type:
1 or 2 family dwe...
Building Type:
N/A
Install cental heating and air conditioning with duct."comply with department order effective date 02/25/2010. permit will expire 30 days from issuance date
Valuation:
N/A
Permit #:
14044-10000-11847
Status:
issued
Fee:
N/A
Permit Type:
1 or 2 family dwe...
Building Type:
N/A
Suppl. permit to permit #09044-10000-11549 for (5) additional exhaust fans for bathrooms mechanical. room and conference rooms. repair relocate and install flex duct and new thermostats. (work is for #208 and #209)
Valuation:
N/A
Permit #:
09044-10001-11549
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Supplemental to permit #11044-20000-13241 for (3) bathroom exhaust fans
Valuation:
N/A
Permit #:
11044-10001-13241
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Supplemental to permit # 08044-10000-09015 to install (2) exhaust fans & perform smoke test for (2) air conditioning air handlers
Valuation:
$0
Permit #:
08044-10001-09015
Status:
Permit Finaled
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/a
Supplemental to permit# 06044-10000-03226 to addition on (7) inlet/outlet & (1) bathroom exhaust
Valuation:
N/A
Permit #:
06044-10001-03226
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Install (2) fan/coils ductwork and duct type detectors for air conditioning system
Valuation:
$0
Permit #:
08044-10000-09015
Status:
Permit Finaled
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/a
Install new ducting
Valuation:
N/A
Permit #:
11044-20000-13241
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Repair relocate & install flex ducts & new t-stat
Valuation:
N/A
Permit #:
09044-10000-11549
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Mechanical for :t i both units #ascer min 13
Valuation:
N/A
Permit #:
80007-0062
Status:
final
Fee:
N/A
Permit Type:
N/A
Building Type:
N/A
Install spiral duct. (6-inlet/outlets)
Valuation:
N/A
Permit #:
09044-10000-04009
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Hvac ducting installation
Valuation:
N/A
Permit #:
06044-10000-03226
Status:
final
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/A
Install gas heater
Valuation:
N/A
Permit #:
02044-10000-08886
Status:
final
Fee:
N/A
Permit Type:
1 or 2 family dwe...
Building Type:
N/A
Electric boiler
Valuation:
$0
Permit #:
99045-10000-00202
Status:
Permit Finaled
Fee:
N/A
Permit Type:
Commercial
Building Type:
N/a
Install cental heating and air conditioning with duct."comply with department order effective date 02/25/2010. permit will expire 30 days from issuance date
Valuation:
N/A
Permit #:
14044-10000-11847
Status:
issued
Fee:
N/A
Permit Type:
1 or 2 family dwe...
Building Type:
N/A
No Description Available
Valuation:
$0
Permit #:
T0500038
Status:
COMPLETE
Fee:
$146
Permit Type:
N/A
Building Type:
N/A
Replace heating and air conditioning
Valuation:
N/A
Permit #:
B201100832
Status:
final
Fee:
$49
Permit Type:
Mechanical
Building Type:
N/A
Scope of work: (n) addition of 642 sqft at rear complete interior rebuild 200a main panel upgrade & (n) evcs in garage relocate furnace in attic
Valuation:
$328,204
Permit #:
2025 112437 RS
Status:
issued
Fee:
$2,925
Permit Type:
Single-family
Building Type:
N/A
Similar Contractors See more
142
BZ Score
$6K
Avg Project
-
Projects
146
BZ Score
$9.2K
Avg Project
-
Projects
138
BZ Score
$14K
Avg Project
-
Projects
Steve Yi Reviews
BuildZoom hasn't received any reviews for Steve Yi. Click here to be alerted when reviews are posted about them.
Recent Buildzoom Projects
Let us find you an HVAC pro in your area today
We'll search our vast network of HVAC Pros and connect
you with one that meets your needs today.
Verified License
BuildZoom confirmed this contractor's license
Steve Yi License info
Verified License
| License # | 1029672 |
| Status | Active |
| State | California |
| Type | Warm Air Heating, Ventilating And Air Conditioning |
| Business Type | Sole Ownership |
- BuildZoom verified this license was active as of March 2026.
Verify this license's status for Steve Yi at the California Contractors State License Board.
This is a sample of licensing data; click here to access a complete history.
Inactive License
| License # | 739614 |
| Status | Inactive |
| State | California |
| Type | Warm Air Heating, Ventilating And Air Conditioning |
| Business Type | Sole Ownership |
- According to the California Contractors State License Board, the status of this license was at one point cancelled. However, this information may have changed. If this is your business, please update your license status.
Check this license's status for Steve Yi at the California Contractors State License Board.
This is a sample of licensing data; click here to access a complete history.
100
BuildZoom Score
Bonded
| Bonded Agent | American Contractors Indemnity Company |
| Bond Value | $15,000 |
Insured
| Workers Comp Provider | Insurance Company Of The West |
18
Permits
- Building permit records show that Steve Yi has worked on 18 permitted projects.
Steve Yi Employees
SY
Steve Yi
Rmo / Ceo / Pres
SY
Steve Yi
Owner