Installing a T series macerator pump

[Rick9619]

Hey gang! I have an EcoVac "uflush" fresh water head to a Y valved overboard/holding tank system. Just thought I would throw this out for ideas and thoughts although I do have a question. Peggy (I know your reading this ) on page 17 and 19 of your book, you say a vented loop "must" be installed in the discharge line for all below the waterline applications. You say the "standards"... do you mean part of the laws? Am I to assume this is in addition to the one I already have on the inlet to the holding tank? Does it still apply downstream of a y valve in the discharge line with of course a seacock at the thru hull? Has anyone else added a T series pump? Or just the logistics of adding a macerator pump period when you didnt have one before.Peggy, as I said when I talked to ya on the phone, I will email ya with pics of the system so you can make your recommendation. Just thought I would see if anyone has done something "outside the holding tank" that works great and of course is legal.Cheers

 

[Peggie Hall HeadMistress]

I'm gonna stay out of this one till I get yr email

Except to note that the SeaLand T-Pump is not a macerator pump. It's an electric diaphragm pump that has been called a "musherator" pump.A macerator pump has a cutting blade (which is the actual macerator...the pump itself if an impeller pump) in it. Diaphragm pumps do not...the diaphragm is a "bellows" that mashes any solids as it propels tank contents out the thru-hull.Maceration isn't necessary to dump a tank. Solid waste is 75% water to start with...it's also broken up as it passes through the toilet pump, so it dissolves VERY quickly in water...which any holding tank has plenty of in it. Quick dissolve TP also turns into tiny little flecks in water. If the wrong type of TP is flushed, it won't dissolve...but if it doesn't clog the toilet, it's likely to jam a macerator pump, but make through a diaphragm pump with no problem.All of which is to say that a manual or electric diaphragm pump is a MUCH better choice as a holding tank overboard discharge pump than a macerator pump...especially when you also factor in the fact that diaphragm pumps can run dry for quite a while without harm, whereas an running dry for more than about 30 seconds is likely to completely fry the impeller in a macerator pump.Send me your email, Rick...I'll answer your questions after I see what your installation looks like.

 

[Bill Roosa]

Vented Loops

ANY TIME you have a thru hull that somehow opens to the cabin (head bowl in this case) you need a vented loop. You need one on the inlet and the "outlet" to prevent - and sinking.AndWhile the engine raw water cooling water thru hull does not open into the cabin it does "open" into the engine so it needs one on the exhaust. You don't need one on the inlet as the raw water pump impeller effectively blocks the line into the engine when it is not running. That is why you should always check your impeller regularly. If you loose an impeller vain and the motor stops with the missing vain in the wrong position you could flood your muffler and then the engine with raw water.

 

[Bill Roosa]

Should have said

opens to the cabin below the water line not opens to the cabin