Sorry, I thought from your first post that the low suction was going to be part of the plumbing, you should have at least 2 suction sources (** for AG owners who read this - your system is fine, all plumbing is easily acessable**), if one goes bad you can still run the pool off of the other, and it helps keep the pump fed. Yes, the numbers look in order, the heater won't fire if there isn't sufficient flow to 'trip' the pressure switch.