seaward s700 installation Perkins 4-108

[jfbishop]

Have moved water heater to new location under galley sink. Heat exchanger nipples on water heater are 5/8"; connections to engine can be 1/2" or 3/4" with hose length by best route approximately 13' each way, 26' round trip. Because availability of bronze plumbing fittings seems to be limited to 1/2" or 3/4", what advise can anyone give regarding best ID hose size to use. Because some of the turn radius (radii) will be tight, can anyone recommend good, better, and best hose type to use.
Thanks

[Steelaway35]

What kind of supply line are you using? I'm installing a Seaward S600 on my boat next week. I'm using 1/2" AquaPex lines into brass fittings on the water heater. I'm not sure what kind of check valve to use quite yet.

I see this is quite an old post and I'd love to hear what you ended up with and how everything turned out!

Thanks!

Kevin