There is a 2S relay, a 2R relay and a 2s-2r relay commonly called a lock-latch relay. Hoistway magnet switches may cause problems with the lock-latch not working correctly, but won't burn a coil open. Are coils going open? Is it always the same coil? Is your control voltage at 115VAC/230VAC or is it higher? Could it be a defective relay? Did it just go open or is it burnt(usually yellow but when burnt turns brown)?
