I am re-plumbing everything connected with the toilet and holding tank with new hoses and a new macerator pump. The current set-up has the toilet discharging directly to the holding tank. The holding tank is emptied either by pump out or macerator pump discharge overboard. There was a plastic T-fitting separating the 1-1/2" hoses that led to the pump or the pump-out deck fitting from the holding tank. If I remember correctly (I've taken it apart already), it was a straight pass thru the T-fitting between the deck cover and the holding tank. The path from the holding tank to the macerator pump had a 90 d bend in the T-fitting, and then another 90 d plastic bend before the hose connected to the pump. The pump discharge is 1" diameter to the thru hole fitting.
So, I'm not really crazy about the T-fitting and I want to replace it with a Y-valve. I want a smoother pass to the macerator pump and I want the ability to close and lock the path to the macerator pump. I empty the tank at sea only when outside the no-discharge zone and the normal position would be closed to the macerator pump when using the pump-out service. I noticed Forespar says their Y-valve is not suitable below water line. I thought I also read that the silicone seal can be damaged by prolonged exposure to sea water.
The Y-valve will be below waterline, but under normal circumstance, the thru hull is closed and the water has to backup past the macerator pump in any case. Typically, the thru hull valve is closed immediately after shutting the macerator pump off. My preferred Y-valve is TruDesign, sold by Raritan, which uses a silicone seal. Since the Y-valve isn't necessarily open to the thru hull, is it ok or would it not be recommended?
So, I'm not really crazy about the T-fitting and I want to replace it with a Y-valve. I want a smoother pass to the macerator pump and I want the ability to close and lock the path to the macerator pump. I empty the tank at sea only when outside the no-discharge zone and the normal position would be closed to the macerator pump when using the pump-out service. I noticed Forespar says their Y-valve is not suitable below water line. I thought I also read that the silicone seal can be damaged by prolonged exposure to sea water.
The Y-valve will be below waterline, but under normal circumstance, the thru hull is closed and the water has to backup past the macerator pump in any case. Typically, the thru hull valve is closed immediately after shutting the macerator pump off. My preferred Y-valve is TruDesign, sold by Raritan, which uses a silicone seal. Since the Y-valve isn't necessarily open to the thru hull, is it ok or would it not be recommended?
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