System Sensor 4WT-B

4-Wire Smoke Detector with 135°F Fixed Heat Sensor

Average rating:

(based upon one review)

The System Sensor 4WT-B is a 4-wire photoelectric smoke detector that also includes a built in 135°F fixed temperature heat sensor. The sensor offers reliable and consistent fire detection for virtually any home or business. Buy the system sensor 4WT-B 4-Wire Smoke from Alarm Grid.
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The System Sensor 4WT-B 4-Wire Smoke Detector with 135°F Fixed Heat Sensor provides reliable fire-protection for residential and commercial locations. The sensor uses a 4-wire configuration and photoelectric technology to detect smoke, while the heat sensor provides added reliability.

As a 4-wire smoke detector, various add-ons are needed to integrate the 4WT-B with an alarm system. You will need an external power relay to drop power to the device once the fire alarm has been cleared. You might also need an external power supply if the panel does not supply sufficient power. An end of line resistor (EOLR) and an end of line power supervision relay are also needed.

The advantage to using a 4-wire smoke is that they can usually be set up with any regular hardwired zone, provided that the right equipment is used. This is not the case with 2-wire smokes, which require special resetting features and addtional current from the zone. However, 2-wire smokes are generally easier to set up, and they are better-suited for DIY users.

As a smoke and heat sensor, the 4WT-B works very reliably using photoelectric technology. This involves using an internal light that becomes refracted when smoke enters the chamber. The 135°F fixed temperature sensor ensures greater consistency in detecting fires. The sensor can also be used for freeze detection, which activates at fixed temperatures of 41°F and lower. The sensor measures 5.3" in diameter, and it has a height of 2.0".

Please note that the System Sensor 4WT-B does not include a built-in sounder. If you want an identical sensor that includes a built-in sounder for alerting building occupants to a fire, then you should consider the System Sensor 4WTA-B instead.

Read here to learn the difference between smoke detectors and smoke alarms. Photoelectric smoke detectors work with an alarm system, and when properly maintained and tested, can last for an indefinite period and do not automatically require replacement after a certain period of time like smoke alarms and CO detectors do.

Brand: System Sensor

Good 4-Wire Smoke Detector
Submitted on 08/23/2019 Alarm Grid

We think the System Sensor 4WT-B is a fine 4-wire smoke and heat detector. However, we encourage our customers who are considering wired smoke and heat detectors to purchase 2-wire devices instead. A 2-wire device will be much easier to set up, and it won't require any extra added equipment.

Adding smoke and heat detectors to your alarm system is an excellent idea. This is the best way you can be sure to receive an automatic emergency response from your local fire department when a fire occurs. You just need to have active central station alarm monitoring service and have smoke and heat detectors properly installed and enrolled with your security system. If you have an interactive monitoring service like Total Connect 2.0, you can also receive alerts regarding any activated smoke and heat detector.

If you have a hardwired system like a Honeywell VISTA System, then it is likely that you will be considering hardwired smoke and heat detectors. When it comes to hardwired smoke detectors for alarm systems, there are two options to choose from. These are 2-wire devices and 4-wire devices. We recommend using 2-wire devices. They are easier to install, and they do not need extra equipment. The only reason to choose a 4-wire smoke detector is that you can use it at any hardwired zone.

When setting up a 4-wire smoke detector, you need more than just the detector itself. You will also need a relay to supervise the smoke detector's power supply, as well as an external power relay that can cut power to the sensor when an alarm is cleared. You may also need an external power supply if your system cannot supply enough power on its own. As for a 2-wire smoke detector, no extra equipment is needed. The only rule with a 2-wire smoke detector is that you must use the device at a designated 2-wire smoke zone that the system will know to automatically reset when an alarm is cleared. For a VISTA System, this is Zone 1. You can wire multiple 2-wire smoke detectors to this zone in parallel.

You really should only go with the System Sensor 4WT-B if you need a 4-wire smoke and heat detector that can be used at any zone. For most users, it just makes more sense to go with 2-wire smoke and heat detectors and use them at the properly designated zone. If you are looking for a good 2-wire smoke detector to use with your Honeywell VISTA System, then the System Sensor 2WT-B is a great option.

As far as the performance is concerned, the 4WT-B works great. Our technicians have found that the 4-wire device responds reliably to smoke and high temperatures in excess of 135 degrees Fahrenheit. This really is a perfectly capable smoke detector. It's just that we recommend going with a 2-wire device instead. We also want to mention that the 4WT-B does not include a built-in sounder. If you want your hardwired smoke and heat detector to include a built-in sounder, you should consider the System Sensor 4WTA-B or the System Sensor 2WTA-B instead.

Bottom line, the System Sensor 4WT-B is a great 4-wire smoke detector. But most DIY users will find that they will have a much easier time going with a 2-wire equivalent. If you are looking for a new hardwired smoke detector, try and see if you can go with a 2-wire device instead. The System Sensor 2WT-B is probably your best option. Additionally, you might also strongly consider the System Sensor 2WTA-B. The System Sensor 2WTA-B is our favorite hardwired smoke and heat sensor, as it uses a 2-wire configuration, and it has a built-in sounder.

* Based on a 10% APR with 12 months financing. APR's will vary between 10% - 30% based on credit score and various factors.