expect A LOT OF exceptions, e.g. 手, 場 (just look at Found in Vocabulary)
There is a good reason to see a vocab as just a word, and Kanji as just letters in that vocab with no real reading for each one. Get a sense of what the vocab is describing (i.e. the image) should be get what reading for the whole vocab.
Just as how to read office and off ice, or I read a book {yesterday / every day}.
Nonetheless, if you hear an unknown vocab, or got a sound comes to mind 
, Kanji readings should make a good guess. But at this point, which kind of reading is getting irrelevant…
This thread – The quick or short Language Questions Thread (not grammar)
It’s OK to keep asking or make a new thread too. (Though the new questions may become different from the current thread title…)