the following are the list of top heat detector manufacturers :

1. esser fire alarm system in Germany
2. Honeywell Gent in United Kingdom
3. simplex fire alarm system in United State
4. notifier fire alarm system in United State
5. system sensor company in United State
6. Eaton fire alarm in United State
7. zeta alarms ltd in United Kingdom
8. hochiki fire alarm in United state
9. protectowire company in United State
10. fire lite in united State
11. panasonic fire & security europe ab in Sweden
12. PineTree Fire alarm in India
13. ARTON fire alarm in Ukraine
14. eds elektronik in Turkey
15. Ningbo Peasway Electronics Co Ltd in China
16. horing lih industrial co ltd in Taiwan
17. Schrack Seconet in Austria
18. eurotech fire alarm in United Kingdom
19. ctec fire alarm in United Kingdom
20. Textel Technologies Pvt. Ltd in India
21. Codesec Fire Detection and Control Systems in Turkey
22. DMtech Ltd in Bulgaria
23. Numens Ambest Electronics Co. Ltd in China
24. Ningbo Sentek Electronics Co. Ltd in China
25. Ampac Pty Ltd in Australia
26. Thermocable (Flexible Elements) Ltd in United Kingdom
27. Linesense Fire Detection Ltd in United Kingdom
28. Senkox Technologies Inc in United State
29. Nohmi Bosai Limited in Japan

Heat detectors are the oldest type of automatic fire detection device. Not considered direct Life Safety devices, these detectors do contribute to the detection of a fire :

• Fixed Detectors alarm when the sensing element reaches a certain set point. Two common ones have 135 and 200-degrees F range. The Fixed element is generally a non-restorable type, and when activated, must be replaced.
• Rate-of-Rise Detectors respond when the rate of temperature increase is greater than an allowable limit (15 degrees in 60 secs.) (placement in a stable environment)  (e.g.. ovens, heating vents, etc.). The Rate-of-Rise element is restorable when conditions return to normal.
• Rate Compensation will respond regardless of the rate of temperature rise.