I goofed. Cost me 2/3 of the water in the pool.

Heater exterior was cool enough to hold my hand on. so I shut off the pump last night. Got up this morning to a muddy mess. One PVC joint failed, and broke free. I assume from residual heat in the firebox.

However, the up side to this is I was able to make the improvements to the heater.

Incoming fill water is measured 63*, yet the pool is holding at 72*, while filling. Current air temp 64*, high today was 68*.

I guess that means the changes to the heater are successful. Looks like I'll be able to get the water back to swimming temperature by tomorrow afternoon. Shooting for 80*+. Anything over that is just gravy......