The Siemens HFP-11 is an addressable, plug-in multi-sensor smoke detector designed for use with Siemens FireFinder XLS fire alarm control panels. This guide covers everything you need. You will find HFP-11 technical specs, wiring details, compatibility information, the recommended replacement, and where to purchase it.
What Is the Siemens HFP-11?
The Siemens HFP-11 (part number 500-033290) is a two-wire, plug-in smoke detector built for the Siemens FireFinder XLS addressable fire alarm system. It combines photoelectric smoke sensing with a thermal element, making it a multi-criteria detector capable of identifying both smoldering and fast-flaming fires. Each HFP-11 communicates individually with the FireFinder XLS panel. Its addressable design means the panel can report the detector’s precise location during an alarm.
The HFP-11 was widely installed in commercial buildings, healthcare facilities, schools, and industrial sites across North America during the peak years of the FireFinder XLS platform. It earned a strong reputation for reliability and stable communication on the Siemens XLS signaling line circuit (SLC).
HFP-11 Technical Specifications
Understanding the technical specifications of the HFP-11 is useful whether you are troubleshooting an existing installation or planning a replacement. The key specs are as follows:
- Part Number: 500-033290
- Detection Type: Multi-sensor (photoelectric smoke + thermal)
- Wiring: Two-wire, plug-in addressable
- Compatible Panel: Siemens FireFinder XLS, FS-250
- Mounting: Plug-in to compatible detector base
- Operating Voltage: Loop powered via XLS SLC
- Operating Temperature: 32°F to 120°F (0°C to 49°C)
- Housing: White low-profile housing
Is the Siemens HFP-11 Discontinued?
Yes — the Siemens HFP-11 has been discontinued by the manufacturer. Siemens phased it out as part of the broader transition away from the FireFinder XLS platform. However, because so many buildings still operate FireFinder XLS systems, demand for HFP-11 replacement units remains high.
Life Safety Consultants carries reconditioned HFP-11 units for customers who need a drop-in replacement without modifying their existing system. These reconditioned detectors are tested and verified before shipping, making them a cost-effective option for keeping an older system operational. View reconditioned HFP-11RC units here.
HFP-11 Replacement: The Siemens OP921
For customers who want a new (not reconditioned) addressable smoke detector compatible with the FireFinder XLS system, the recommended replacement is the Siemens OP921. The OP921 is a photoelectric smoke detector that uses forward-scatter optics for reliable detection of smoldering fires. It is fully compatible with the Siemens FireFinder XLS and FS-250 systems. It also uses the same plug-in base as the HFP-11, making it a straightforward swap.
Transitioning from the HFP-11 to the OP921 typically does not require panel reprogramming. Both devices communicate on the same XLS SLC. In most cases, a fire alarm technician can replace the detector head at the base without rerouting any wiring — a significant advantage in reducing both labor time and cost.
When Should You Replace an HFP-11?
Manual pull stations and smoke detectors have defined service life guidelines under NFPA 72. For smoke detectors, manufacturers and codes generally recommend replacement after 10 years of service. If your HFP-11 detectors are approaching or past that threshold, proactive replacement is a sound investment in life safety and code compliance.
Beyond age, you should also consider replacing an HFP-11 when it generates frequent nuisance alarms, fails self-test diagnostics, or triggers a trouble signal at the panel. Communication faults on the XLS loop can sometimes be resolved by simply cleaning the detector chamber, but persistent faults usually indicate the detector needs replacement.
If your FireFinder XLS system is approaching end-of-life and you are planning a full panel upgrade, consider coordinating detector replacement at the same time. Replacing detectors in conjunction with a panel upgrade reduces future maintenance complexity and ensures all devices are on a common service schedule.
Order the HFP-11 or Its Replacement
Life Safety Consultants is your source for Siemens FireFinder XLS parts. We stock both reconditioned HFP-11 units and the new Siemens OP921 replacement. Our team can help you determine the right option for your system and confirm compatibility before you order.
To place an order or ask a question, call us at 1-888-557-0558 or browse our full Siemens fire alarm parts catalog. We offer fast shipping and are available to assist fire alarm contractors, facilities managers, and building owners across the country.
