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Macerating Toilet And Sewage Pump System Guide




Macerating Toilets and Sewage Pumping Systems are often a good choice for the installation of a bathroom in a basement or, other location where gravity drainage is not possible. These macerating systems range in capability from a half bath with just a toilet and lavatory sink up to systems that can handle even a washing machine that is drained to a laundry tub first.

In the past waste systems that could not drain by gravity were limited to ejector pits where the installation involved cutting the concrete floor, installing and ejector pit and pump in the ground below the floor and trenching the associated drain pipes below the floor to the pit. The ejector pit and pump remains the most desirable method and provides the highest value but there are many circumstances where tanks below grade become to expensive or risky to install such as high groundwater where compromising the floor makes a flooding risk or, ledge below the foundation makes excavation for a pit impossible or, expensive.

Several manufacturers offered systems with a plastic tank and pump that could be mounted on top of the floor without breaking open the concrete. An example of this type system would be the Zoeller Qwik Jon models 100, 101, & 102 and the Liberty LowPro41LP system. With this type of system a standard toilet is mounted on the top of the tank with a raised floor framed with 2 X 6’s for the toilet and any tub or shower installed to allow drainage to the tank. Many people objected to this step up bathroom or, did not have the necessary ceiling height in a basement for this type of installation.

The introduction of macerating toilets and pump systems removed the requirement for the entire bathroom floor to be raised. However, standard toilets could no longer be used, as the systems were developed to use proprietary rear outlet toilets to mate to the tank and macerating pump. Early systems had a tank that mounted behind the toilet, between the toilet and the wall, with later tanks that could be mounted inside or behind a wall. With the macerating toilet and pump systems the installation of a shower or, tub would still require a raised floor of at least 2 X 6’s to allow the drain piping for the shower or, tub. In a macerating pump blades are used to chop up solid waste such as toilet paper and feces to liquefy the waste being discharged. This macerating process or, liquefying allows waste to be discharge through a discharge pipe as small as ¾” diameter. These pumps are actually quite powerful in terms of pumping capability and some can lift in the area of 20’ and have a horizontal discharge run in the area of 150’, you should check the specifications for the unit you are considering.

SaniFlo was one of the earliest to offer the macerating toilet and pump system and they offer three options for a half bath with a toilet and lavatory sink. The have the SaniTop, which is a pump mounted directly behind a toilet and has three toilets that can be used with it. The SaniCompact is a floor mounted toilet that flushes entirely using 1.1 gallons per flush with the pump enclosed in the toilet base and a lavatory sink can drain to the toilet. The SaniStar is a wall mount toilet that operates like the SaniCompact.



SaniFlo offers three units, which can handle a full bath with a raised tub or, shower. The SaniBest and SaniPlus are very similar in that they can mount either directly behind the toilet or, on the other side of the wall when an extension tube from the toilet is used. The SaniPlus offers a higher capacity pump, which can handle the flows from a washing machine. The SaniBest and SaniPlus also must be used with one of three SaniFlo toilets. The SaniPack Is similar but is mounted inside the wall cavity and uses a standard wall mounted toilet plumbed to the tank. SaniFlo also offers the SaniGrind system which can be used with a conventional floor mounted toilet but requires the toilet to be mounted on a minimum of a 2 X 6 framed raised floor.

Zoeller recently entered the Macerating toilet and pump system manufacturers when they introduced the Zoeller Qwik Jon Ultima model 202 & 203. The Zoeller Qwik Jon Ultima model 202 can be installed either free standing behind the toilet or, in the wall behind the toilet. The Ultima 202 uses a rear discharge toilet supplied by Zoeller as part of the kit. The Zoeller Qwik Jon Ultima model 203 is essentially the same as the 202 and does not come with the toilet but uses a rear discharge toilet, which is available from some toilet manufacturers. The Zoeller Qwik Jon Ultima can also be used to drain a lavatory sink and tub or, shower but the tub or, shower would have to be raised to accommodate the drain.



Liberty Pumps also recently entered the Macerating toilet and pump system manufacturers when they introduced the Liberty Ascent Macerating Toilet System. The tank and pump for the Liberty Ascent model ASC-1 can be mounted free standing behind the toilet or, behind the wall when used with the extension tube. Liberty has one toilet, comprised of the model ASC-2 tank and the ASC-3 bowl available in elongated white only, which can be used with the system. The Liberty Ascent model ASC-1 can also provide drainage for the lavatory sink and a tub or, shower with the shower being on a raised platform to accommodate the drain.


While gravity drainage from a bathroom offers the lowest cost and highest reliability, and most cases being required by code if at all possible. The Macerating Toilet system are an excellent choice for a bathroom requiring pumping up to a drain when you do not want to break the concrete slab to install piping and an ejector pit.