Post edited 4:44 pm – December 17, 2009 by Steve Pooler
Sounds like you have a pump that draws heavy amperage causing the 6PRP to weld it's internal "Triac" (solid state contactor)
The problem with the Marine Air pump relays is they can't handle much amperage…and when they fail…The only part that is available is the complete board or the box with it….
A Cruisair PR8X relay is good for up to 8 units and the "Triac" inside that unit is replaceable plus will handle up to 25 amps (All Day)….Not likely to fail in pump duty, and they actually use the same triac for compressor duty…
If your pump is drawing more than the Marine Air 6PRP can handle…It's likely drawing too much anyway, and that may be your first problem, but without info on what it's actually drawing & what voltage it's wired for, I can't help much more…
There should be a data plate on the side of the motor giving rated amp specs…I would start by finding out if your actual draw matches specs for the voltage you are running it on (most larger pumps have dual voltage motors)
How many units do you have and what are the sizes of each ?
We can calculate how much flow you need and then see if the proper pump is in fact installed…sometimes much larger pumps than are needed get installed for several possible reasons, any of which should have been repaired first but instead they throw in a larger pump thinking that will solve all…
A model or description of the pump would help too…
Steve~