Macerator, how does it work?

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king5899

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I noticed I have a Macerator in my boat, and was curious how it works. I see a thru hull that goes up and connects to the macerator and then a hose coming from a Y valve and I believe another hose. The Y valve is pointed to the head and then the holding tank so I assume I would need to turn that to the tank and the macerator, as well as open the thru hull that is currently closed. I didn't see a switch for it anywhere.

If anyone could explain how it should work I would apreciate it. I am aware it shouldn't be used if avaoidable and can only be discharged outside of 3 miles off the coast, but am just curious.

MJK
 
The definition of the word "mascerate" (British spelling - U.S. spelling usually drops the "s", the common American spelling is macerate) is "to soften."

There are two common uses: 1) a grinder/pump combination that is used to grind up and empty the contents of your holding tank into the outside water; 2) a grinder built into a marine toilet, to chop up the effluent before it goes into a holding tank or treatment system, to reduce chances for clogging in the lines.

The most common application, where the word "macerator" is most frequently used, is actually "macerator pump," a pump that is used to grind up and empty your holding tank's contents into the outside water. Even though many boats are equipped with macerator pumps, in the U.S. it is illegal to use them to empty your holding tank into the outside water. There's a $2000.00 Federal Fine if you get caught. You may only empty your holding tank into the outside water if you are 3 miles or more offshore. In the Florida Keys, due to the shallow water there, you must be a minimum of 12 miles offshore in order to legally empty your holding tank into the outside water.

The same law applies to marine toilets - it is illegal to discharge a marine toilet (raw sewage) into the outside water ANYWHERE in the U.S. If you are more than 3 miles offshore, you can then discharge a marine toilet directly into the water, unless you are in the Keys, where the distance is 12 miles.
 
quote:
Originally posted by king5899

I noticed I have a Macerator in my boat, and was curious how it works. I see a thru hull that goes up and connects to the macerator and then a hose coming from a Y valve and I believe another hose. The Y valve is pointed to the head and then the holding tank so I assume I would need to turn that to the tank and the macerator, as well as open the thru hull that is currently closed. I didn't see a switch for it anywhere.

If anyone could explain how it should work I would apreciate it. I am aware it shouldn't be used if avaoidable and can only be discharged outside of 3 miles off the coast, but am just curious.
Click to expand...

Vic explained what a macerator is and does and explained the law.

Reading your post, I suggest you get someone local to look at how your system is set up and then explain it to you. You might want to buy this book:

51MVVWQ34HL._BO2,204,203,200_PIsitb-sticker-arrow-click,TopRight,35,-76_AA240_SH20_OU01_.jpg


and study it. This will help you to know how these systems work.
 
I had the same setup on my cruisers.
The Y valve connects 3 pipes.
1 to the holding.
1 to the wast cap outside boat
1 to the macerator.
For pumpout the y valve must point to tank and waste cap.
For macerator the y valve must point to tank and macerator.
Tank is always in the equation.

To use macerator:

1) Change Y valve to macerator and tank
2) Open SeaCock that comes out of macerator
3) Turn macerator on.
4) When done, you will hear it by sound of pump, it will whine very loud.
5) Shut it down and CLOSE seacock. If you leave seacock open you could get seawater backing up into tank.
6) Close Y valve to other position.

I highly recommened you leave the seacock closed and disconnect the wire on macerator so the switch can't be hit accidently.
Also never run pump dry, they will burn out quick.
 
quote:
Originally posted by CurrentSea

I had the same setup on my cruisers.
The Y valve connects 3 pipes.
1 to the holding.
1 to the wast cap outside boat
1 to the macerator.
For pumpout the y valve must point to tank and waste cap.
For macerator the y valve must point to tank and macerator.
Tank is always in the equation.

To use macerator:

1) Change Y valve to macerator and tank
2) Open SeaCock that comes out of macerator
3) Turn macerator on.
4) When done, you will hear it by sound of pump, it will whine very loud.
5) Shut it down and CLOSE seacock. If you leave seacock open you could get seawater backing up into tank.
6) Close Y valve to other position.

I highly recommened you leave the seacock closed and disconnect the wire on macerator so the switch can't be hit accidently.
Also never run pump dry, they will burn out quick.

Click to expand...


Where was your switch? I can't locate one.

MJK
 
also to comply with rules, the handle on the seacock must be removed (in the closed position) or the Y valve handled must be padlocked or secured with a zip tie.

there are two type of discharge pumps... the impeller macerator and the bellow pump. technically, the bellow pump is not a true macerator but it can be run dry without damage and it last 5 times longer than the POS Jabsco macerators...

if the system is installed properly, water can not come back in the tank if you leave the sea cock open but as CS suggested it's a good idea to keep it closed.
 
My macerator switch was in my AC/DC panel.
That was the only switch.
 
Mine has a switch that operates from key (only) in the head compartment.

Is this good enough to satisfy regulations or must I also secure the Y handle?
 
Doug, most (but not all) boarding officers will accept the key switch. If you get a young guy who is all full of himself, he may give you some grief. Best thing if that happens, is to plead stupidity, and say you didn't know, and that you won't do it again. Usually, they'll let you off with just a warning.
 
quote:
Originally posted by Vic Willman

Doug, most (but not all) boarding officers will accept the key switch. If you get a young guy who is all full of himself, he may give you some grief. Best thing if that happens, is to plead stupidity, and say you didn't know, and that you won't do it again. Usually, they'll let you off with just a warning.
Click to expand...


My boat was built (at the factory) with a pushbutton switch to operrate the macerator. No "Y" valve, no seacock (discharge is above the waterline). The holding tank has two outlets, one to the macerator and one to the deck fitting.

I replaced the pushbutton switch with a key switch and I don't keep the key in the switch.

That's about the best I can do. Apparently the PO didn't have any problems even with the push button switch.
 
i've seen boats with factory two spring loaded rockers which must be held for the pump to run... that's even grayer in my opinion than a key switch!

the USCG regs do not specifically list what is acceptable, it's kind of an open ended list. A key switch should be acceptable as logn as the key isnt' left in.
 
Pascal's right; if the key isn't in the switch when you get boarded, they'll usually accept that as a no discharge situation.
 
quote:
Originally posted by CurrentSea

My macerator switch was in my AC/DC panel.
That was the only switch.

Click to expand...


Same here. All waste goes to the holding tank. There is no "Y" for overboard discharge directly from the head.

The holding tank has two outlets; one is the macerator which discharges overboard above the water line and the other goes to the pump out fitting.

The only switch is a regular toggle on the breaker panel.

I've had a USCG Aux inspection done last year and they said it was acceptable.

Bob
 
quote:
Originally posted by rnbenton

quote:
Originally posted by CurrentSea

My macerator switch was in my AC/DC panel.
That was the only switch.

Click to expand...


Same here. All waste goes to the holding tank. There is no "Y" for overboard discharge directly from the head.

The holding tank has two outlets; one is the macerator which discharges overboard above the water line and the other goes to the pump out fitting.

The only switch is a regular toggle on the breaker panel.

I've had a USCG Aux inspection done last year and they said it was acceptable.

Bob

Click to expand...


Bob,

My setup is exactly the same as yours, however I've been told on this forum by some very knowledgeable ROs that minus the keyswitch or wiring the outlet seacock shut that I am actually in violation and subject to a big a$$ fine, even ifI don't actually pump overboard.

It's kind of like having a fast car and getting a speeding ticket unless you leave four of the spark plug wires off.

RWS
 
[/quote]
Bob,

My setup is exactly the same as yours, however I've been told on this forum by some very knowledgeable ROs that minus the keyswitch or wiring the outlet seacock shut that I am actually in violation and subject to a big a$$ fine, even ifI don't actually pump overboard.

It's kind of like having a fast car and getting a speeding ticket unless you leave four of the spark plug wires off.

RWS

[/quote]
Hmmm, guess I'd better do some further checking. The main reason I had the USCG Aux inspection done was my head set up which they said was OK. But, some of the guys on here are pretty smart so I will heed their information.

Actually, I have no discharge seacock, only a thru hull above the waterline. So I guess I need to install a key switch. That would at least prevent accidental pumping. (I guess)Whatever makes the "Man" happy and keeps me from getting a big fine. :)

Thanks for the info,
Bob
 
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