Steve,

I have read your posts on the Meridian Owners forum and am really impressed with your knowledge and advice. Maybe you, or the members can help me…

I decided to end my 2 year problem today with hpf on my salon ac units (under the dash/helm). We created a process where we could continuously circulate a low mix of ospho and water throughout the entire system,  but bypassing the water pump, thinking that there MUST be a blockage somewhere. We didn't get much debris out of any line, mostly full flow. Every line is completely clean, with full flow through all systems and out the discharge thru-hulls when we were on our system powered by a little bilge pump. When we put the system back together ad turned it back on, we got hpf in the salon units almost immediately! I then connected the water supply directly from the boat pump to ONLY the bridge units and it ran great, no hpf, and the best flow I have EVER had out of the discharge thru hulls. I then hooked the supply line from the boat pump directly to ONLY the lateral lines for the stateroom units. Great flow, great discharge. The only thing we can figure out is that the pump is not pumping enough water to supply all of the units, ESPECIALLY the bridge/salon unit.

I have a 2007 Meridian 411, with 4 AC's, off of one thru hull.

Thanks,

Paul