Can I use BT139-800 or BT139-800E equivalent Triac for T16C8 ?

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Joined Jul 12, 2022
Can I use BT139-800 or BT139-800E ?
I am a beginner in electronics and trying to fix 875VA & 675VA inverter boards.

Both inverters have problem in charging section. one inverter is taking high current from battery while inverter is on and then battery low indicates then inverter goes off and another inverter is taking high current while charging battery. but both inverters are making noise.
somehow found that triac may be the faulty one.
also need to identify the value of the those variable preset.
Please check the zip file for inverter PCB. PICTURE Link0ux1lt6254991.jpg
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Joined Nov 18, 2020
In short, yes you can as the BT139-800 Series of Triacs are all rated at 800Vdrm and 16A It(rms). They also have similar Surge On State Current Itsm ratings of 140 - 155 / 170. Make sure they are mounted on heatsinks with a high performing thermal transfer compound, and insulating pads if required.