The water heater is probably set up to prove vent before allowing combustion . The unit measures pressure differential on either side of the blower with a pressure switch and if it fails a certain number of times it will lock out until manually reset . Check your vent line for any obstruction , and then inspect the switch for damage . some of them use a rubber membrane and can fail after enough time . <| sep |> That ' s interesting . I find the idea of a PTA running a school to be . Terrifying . But I guess if they are so sought after , they must be pretty good . <| sep |> I mean , I ' m pretty sure Echo would make for a good attacker as well . <| sep |> No shit . I know its the internet , but take a joke . <| sep |> I would like more love for witches from that costume contest . It ' s a shame , they made several outfits available for more than one class but so far none for witches .