Updated: Jun 16, 2026
Location and Projects
Address
7159 HARLAN LANE, Sykesville, MD, 21784
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Thomas Stern HVAC/Mechanical Contractor
Thomas Stern, 7159 Harlan Ln, Sykesville, MD (Employee: Thomas Darren Stern) holds a Heating, Ventilation, Air Conditioning And Refrigeration license and 4 other licenses according to the Maryland license board.
Their BuildZoom score of 104 ranks in the top 9% of 58,058 Maryland licensed contractors.
Their license was verified as active when we last checked. If you are thinking of hiring Thomas Stern, we recommend double-checking their license status with the license board and using our project planner to get competitive quotes.
Thomas Stern Contact Information
Phone Number: (301) 912-1415
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Address: 7159 HARLAN LANE, Sykesville, MD 21784
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This is a sample of this contractor's permits. Click here to access their complete permit history.
Main level installation of a 1/2 inch gas line for fireplace installation and 3/4 gasline for a range
Valuation:
N/A
Permit #:
P25001155
Status:
issued
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replace 60 000btu 92% gas furnace with a bryant 60 000 btu 92% gas furnace. model #912se36060m14
Valuation:
N/A
Permit #:
M25000502
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Install 2 qty 24 000 btu ductless mini split systems
Valuation:
N/A
Permit #:
M25000381
Status:
complete
Fee:
$138
Permit Type:
N/A
Building Type:
N/A
Installation of 390cfm range hood vented directed out back on an exterior wall
Valuation:
N/A
Permit #:
M25000168
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Addition of 2 ton duct system , 8 supplies 2 returns and installation of a bryant 24, 000 btu heat pump model# 215san024 and a air handler model #fjdnx030 with a 10 kw heat kit. energy method = prescriptive method
Valuation:
N/A
Permit #:
M23001213
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Replace (1) 80 000 btu gas furnace with a 80 000 btu gas furnace. furnace is located in the basement
Valuation:
N/A
Permit #:
P25002314
Status:
complete
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replace 80 000 btu gas furnace with same in basement
Valuation:
N/A
Permit #:
P25000566
Status:
complete
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Extending existing duct work to supply basement with heating and air conditioning. furnace and air conditioning are adequate size for basement and existing house. 4 supplies has existing return
Valuation:
N/A
Permit #:
M21000875
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Install 3 zone 2 ton fujitsu ductless heat pump system 1-aou24rlxf outdoor unit 3-asu9rlf indoor units (work being down downstairs) single family dwelling energy method = prescriptive method
Valuation:
N/A
Permit #:
M21000298
Status:
complete
Fee:
$182
Permit Type:
N/A
Building Type:
N/A
Replace 2.5 ton air conditioning system with a 2.5 ton bryant legacy air conditioning system
Valuation:
N/A
Permit #:
2026-12834-MECH
Status:
issued
Fee:
N/A
Permit Type:
N/A
Building Type:
N/A
Replace 80 000 btu furnace in basement
Valuation:
N/A
Permit #:
P25000444
Status:
issued
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replace 60 000 btu natural gas furnace
Valuation:
N/A
Permit #:
P25000049
Status:
issued
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replace 100 000 btu furnace with same
Valuation:
N/A
Permit #:
P25000422
Status:
issued
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replace 45 000 btu gas furnace
Valuation:
N/A
Permit #:
P25000744
Status:
complete
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replace 80000 btu gas furnace
Valuation:
N/A
Permit #:
P25000051
Status:
issued
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Residential hvac addition alteration permit
2024-06-07
Installation of air to air heat pump and a air hadler in crawl space with duct work for addtion. energy method = prescriptive method
Valuation:
N/A
Permit #:
M24000609
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Replace 2 ton attic heat pump with 3 ton 5 stage high efficiency heat pump and extend existing duct work to new addition
Valuation:
N/A
Permit #:
M21000853
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Residential plumbing addition alteration permit
2021-05-30
Sfd: install gas fixtures: 1- fireplace (main level) 1- fireplace (basement) manifold and gas regulator
Valuation:
N/A
Permit #:
P21002168
Status:
complete
Fee:
$83
Permit Type:
N/A
Building Type:
N/A
Replace 80, 000 btu gas furnace with a 80, 000 btu gas furnace
Valuation:
N/A
Permit #:
P24002036
Status:
complete
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
Replaced 100, 000btu oil furnace
Valuation:
N/A
Permit #:
P23001718
Status:
complete
Fee:
$55
Permit Type:
N/A
Building Type:
N/A
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Verified License
BuildZoom confirmed this contractor's license
Thomas Stern License info
Verified License
| License # | 2365 |
| Status | Active |
| State | Maryland |
| Type | Heating, Ventilation, Air Conditioning And Refrigeration |
- BuildZoom verified this license was active as of April 2026.
Verify this license's status for Thomas Stern at the Maryland Department of Labor, Licensing & Regulation.
This is a sample of licensing data; click here to access a complete history.
Verified License
| License # | 72370 |
| Status | Active |
| State | Maryland |
| Type | Plumbers |
- BuildZoom verified this license was active as of April 2026.
Verify this license's status for Thomas Stern at the Maryland Department of Labor, Licensing & Regulation.
This is a sample of licensing data; click here to access a complete history.
Verified License
| License # | 64451 |
| Status | Active |
| State | Maryland |
| Type | Plumbers |
- BuildZoom verified this license was active as of April 2026.
Verify this license's status for Thomas Stern at the Maryland Department of Labor, Licensing & Regulation.
This is a sample of licensing data; click here to access a complete history.
Inactive License
| License # | NAT-52179-3 |
| Status | Inactive |
| Nation | Environmental Protection Agency |
| Type | Renovation |
- According to the United States Environmental Protection Agency, 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 Thomas Stern at the United States Environmental Protection Agency.
This is a sample of licensing data; click here to access a complete history.
Inactive License
| License # | NAT-52179-2 |
| Status | Inactive |
| Nation | Environmental Protection Agency |
| Type | Renovation |
- According to the United States Environmental Protection Agency, 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 Thomas Stern at the United States Environmental Protection Agency.
This is a sample of licensing data; click here to access a complete history.
104
BuildZoom Score
213
Permits
- Building permit records show that Thomas Stern has worked on 213 permitted projects.
Thomas Stern Employees
TS
Thomas Darren Stern
Owner
TS
Thomas Stern
Owner
Thomas Stern worked with our builder and seemed to do a good design on our addition, a second story add-on. But we still have the occasional condensation problem on a small section of ductwork in the basement that drips on the floor when the humidity is very high, even though we have a dehumidifier going full time down there.
Our old system blew before the remodel was scheduled and he quickly got us a temporary used system to get us through the summer for very cheap.
They put in extra time to make sure everything was working when they installed the new AC and when I asked him to help with a programmable thermostat we had put in, it appeared he didn't like to work with them and insisted we could manage fine ourselves. Unfortunately, it really didn't work with the AC and we had to have them back when things heated up, although they were quick to get out and the technician found a way to fix it, but then made it sound like it wasn't really his job.
Their main business is full installs, not basic repairs. I think in a normal house situation where you need a new system installed and you have them do everything, including the thermostat, they would be good to have and they were very professional and didn't leave things a mess. Also, I think the price was very competitive.