Pre-flop, it is a call because of the implied odds.

On the flop, The guy all-is is almost always on a good draw A [img]/images/graemlins/heart.gif[/img] or k [img]/images/graemlins/heart.gif[/img] or simply a pair and a [img]/images/graemlins/heart.gif[/img].

The caller needs to have a [img]/images/graemlins/heart.gif[/img], there's no way he calls with a set, there's enough money involved to risk to loose it to a drawing hand, so with 2 pairs and better he should ahve go all-in. With the nuts, he should call, so 2 [img]/images/graemlins/heart.gif[/img] with 1 really good (A or K) he should call. So he has at least 1 heart.

If you push, he will call 100% of the time so there's no FE, I would do As a stop n Go (on the turn instead of the flop, if it's a non-heart. So I call the flop.

Turn is a [img]/images/graemlins/heart.gif[/img], in my mind he gt his flush and the first guy all-inb should have too, so there's no point of pushing all-in, there's no side pot and you will only be called by better hands.

River? Check unless I improve to a boat. I don't know if I would call a bet, I don't think so...