Hello
We had a trip yesterday on our DLN1 7EA. Everything running normal, running just above our turndown limit of55MW (up in Alberta Canada, GTG is indoors). When suddenly we got a trip from our CO2 chemtron unit. The co2 let go to zone 2, load compartment, at investigation there was no fire and temperature in the load compartment seemed fine, so we manually isolated the CO2 from the tank. No evidence of an actual fire, the load tunnel temperatures are not trend able so I dont know what they got to. But they alarm at about 220C, and trip the GT at 257C. The heat detectors are not set to go off till 385C, but they did activate. Our first thought was an issue with the fire detectors, seemed unlikely since you need 2oo4. But never the less we meggered the wires back to the chemtron PLC, found zero issues. Everything looked fine with the detectors themselves as well. We had the chemtron unit fully checked out in May 2018 and no issues were found, everything worked great. So we talked to the service man from Firecheck and he had mention he seen in the past the fire damper on the load compartment exhaust line can slam shut because a little hook can vibrate loose. This will then lead to no airflow through the compartment and it will get hot enough to set off the heat detectors. We checked the damper and yes it was closed, but when the CO2 system activates it also closes the damper. So we dont really know what came first, did the damper close because the hook came out and gave us high temps. Or did something else set off the heat detectors and CO2 closed the damper? We dont believe we had a board issue with the chemtron unit since everything reset fine. Has anyone had a similar experience? We put the hook back in since we did find it on the ground and pinched it with a pair of pliers so it cannot vibrate out if that is what actually happened.
Thank you
We had a trip yesterday on our DLN1 7EA. Everything running normal, running just above our turndown limit of55MW (up in Alberta Canada, GTG is indoors). When suddenly we got a trip from our CO2 chemtron unit. The co2 let go to zone 2, load compartment, at investigation there was no fire and temperature in the load compartment seemed fine, so we manually isolated the CO2 from the tank. No evidence of an actual fire, the load tunnel temperatures are not trend able so I dont know what they got to. But they alarm at about 220C, and trip the GT at 257C. The heat detectors are not set to go off till 385C, but they did activate. Our first thought was an issue with the fire detectors, seemed unlikely since you need 2oo4. But never the less we meggered the wires back to the chemtron PLC, found zero issues. Everything looked fine with the detectors themselves as well. We had the chemtron unit fully checked out in May 2018 and no issues were found, everything worked great. So we talked to the service man from Firecheck and he had mention he seen in the past the fire damper on the load compartment exhaust line can slam shut because a little hook can vibrate loose. This will then lead to no airflow through the compartment and it will get hot enough to set off the heat detectors. We checked the damper and yes it was closed, but when the CO2 system activates it also closes the damper. So we dont really know what came first, did the damper close because the hook came out and gave us high temps. Or did something else set off the heat detectors and CO2 closed the damper? We dont believe we had a board issue with the chemtron unit since everything reset fine. Has anyone had a similar experience? We put the hook back in since we did find it on the ground and pinched it with a pair of pliers so it cannot vibrate out if that is what actually happened.
Thank you