Siemens fire alarm equipment is installed throughout large commercial, healthcare, industrial and campus buildings, and those systems are typically serviced over long lifecycles rather than replaced. That is where sourcing parts gets difficult, and it is what this collection is built around.
The Siemens devices we keep in stock:
- Siemens smoke detectors - photoelectric, optical, multi-criteria, and combination optical, heat and carbon monoxide sensors
- Thermal and heat detectors
- Duct smoke detectors and duct housings
- Detector bases, including standard, low profile surface mount and sounder bases
- Addressable monitor, interface and dual input modules
- Manual pull stations, horns, strobes, horn strobes and speaker strobes
- Power supplies, NAC expander boards and device programmers
Siemens supersedes part numbers regularly, and detectors and interface modules go out of production while the systems using them stay in service. We stock current and discontinued Siemens parts, including the successor devices for models that have been replaced. If you cannot find what you need, submit the part number on our quote page.

Siemens
Siemens HFP-11 (500-033290) Intelligent Fire Detector
Sale price$378.30
Regular price$453.96
In Stock
Siemens
Siemens DPU (500-033260) Device Programmer Loop Tester
Sale price$1,235.00
Regular price$1,482.00
In Stock
Siemens
Siemens FP-11 (500-095112) Multi-Criteria Fire Detector
Sale price$259.20
Regular price$311.04
In Stock
Siemens
Siemens FDBZ492-HR (S54319-B23-A1) Duct Detector 2-Wire
Sale price$173.95
Regular price$208.74
In Stock
Siemens
Siemens FDO421 (S54320-F4-A1) Smoke Detector
Sale price$117.60
Regular price$141.12
In Stock
Siemens
Siemens XTRI-R (S54370-B1-A1) Addressable Monitor
Sale price$114.50
Regular price$137.40
In Stock
Siemens
Siemens OOHC941 (S54320-F8-A2) Optical and Heat and Carbon Monoxide Detector
Sale price$205.30
Regular price$246.36
In Stock
Siemens
Siemens XTRI-D (S54370-B2-A1) Intel Interface (Replaces HTRI-D)
Sale price$122.00
Regular price$146.40
In Stock
Siemens
Siemens OOH941 (S54320-F7-A2) Multi-Criteria Fire Detector
Sale price$109.25
Regular price$131.10
In Stock
Siemens
Siemens SL2SCW-F (S54329-F198-A1) Strobe Ceiling Mounting
Sale price$84.55
Regular price$101.46
In Stock
Siemens
Siemens HTRI-D (500-033360) Dual Input Module
Sale price$345.85
Regular price$415.02
Contact Us for Alternatives
Siemens
Siemens DPU-C1 (500-033990) DPU Carrying Case
Sale price$172.05
Regular price$206.46
Not in stock - available on backorder - lead time on request
Siemens
Siemens SL2HSWR-F (S54329-F99-A1) Horn Strobe
Sale price$120.95
Regular price$145.14
In Stock
Siemens
Siemens HTRI-R (500-033300) Single Interface
Sale price$345.85
Regular price$415.02
Contact Us for Alternatives
Siemens
Siemens PAD-3 (599-699189) Distributed Power Supply Unit
Sale price$618.90
Regular price$742.68
Only 27 units left
Siemens
Siemens FDOOTC441 (S54320-F8-A1) Dual Optical Heat and Carbon Monoxide Detector
Sale price$281.50
Regular price$337.80
In Stock
Siemens
Siemens SL2SPSCW-F (S54329-F165-A1) Speaker Strobe
Sale price$133.90
Regular price$160.68
In Stock
Siemens
Siemens XMS-D (S54321-F8-A1) Manual Addressable Dual Pull Station
Sale price$131.20
Regular price$157.44
In Stock
Siemens
Siemens OH921 (S54320-F6-A2) - (Replaces HFPT-11)
Sale price$54.55
Regular price$65.46
In Stock
Siemens
Siemens PAD-4-6A (Complete 6 Amp PAD-4 Kit Enclosure)
Sale price$709.55
Regular price$851.46
Contact Us for Alternatives



