An Introduction to RV Macerator Toilets

Your RV toilet won’t be the topic of many chats around the campfire unless it’s a horror story. That should never be the case if you have a dependable macerator toilet that reduces clogs and other problems in your black water system. 

If you want to add a second toilet to your RV or even upgrade your old one to a system that won’t leave unpleasant odors, and prevents clogs then a macerator toilet may be what you’re looking for.

In this guide, we break down this toilet’s mechanics and pros and cons, and we teach you how to dump the waste.

What Is an RV Macerator Toilet?

An innovative take on the traditional white gravity flush toilet, the RV macerator toilet uses built-in stainless steel blades to grind up solid waste and TP into a slurry and pump it to the black water tank.

This helps smooth out the poop pyramid issues and make the process of dumping your tanks an uneventful process. It even prevents the smell of the sewage system wafting into your living space. 

Another reason for its popularity stems from the fact that RVers can install a second macerator toilet without needing to be over top of the black tank or cutting holes in the RV floor.

How Does an RV Macerator Toilet Work?

Before we get to how a macerator toilet works, let’s break down what it is made up of so the jargon is easier to understand. 

An RV macerator toilet essentially contains:

  • A series of stainless steel blades
  • A built-in electric motor
  • An attached pump

At first glance, a macerator toilet looks exactly like a typical commode, but when you go to flush the waste, the process is more than just pressing a lever. At the push of a button, an RV macerator toilet starts its flushing process, which entails the following procedure:

  • First, the built-in electric motor powers the stainless steel blades, and they grind up the solid waste including toilet paper.
  • The waste slurry is then discharged under pressure to the black tank through a pump.
  • By this time, it’s almost liquid which leaves fewer solids to potentially cause blockages in your black water system.

RV macerator toilets use the same process for solid and liquid waste. The only difference is that less water is used to flush down liquid waste as it does not require grinding. Check out my guide to RV toilet water use and how to properly flush.

Why Use a Macerator Toilet in an RV?

There are a lot of benefits of using an RV macerator toilet, and it has helped many RVers improve their travel experience. Following are a few advantages of RV macerator toilets:

  • Easy Flush

An RV macerator toilet has a simple push button method of flushing waste. As long as you have 12v dc electricity to power the motor, it will work as promised.

  • Versatile Installation

Since the waste is pumped to the black water holding tank, an RV macerator toilet does not need to be situated directly over it. This allows RVers to install the macerator toilet anywhere — even over a Class A coach engine.

  • Prevents Clogs

Because an RV macerator toilet flushes down the waste after grinding it up into a slurry, the tank is less likely to clog. This is especially helpful if you’re using a portable waste holding tank or tote to expand your RV sewer system capacity.

  • Odor-free

An RV macerator toilet is sealed from the black water tank so that no pungent odors waft through the RV when the waste has been flushed.

  • Environmentally-friendly

An RV macerator toilet uses a smaller amount of water to flush solid and liquid waste as compared to some other toilet systems. This helps save water which is better for the environment and preserves your fresh water supply. Here’s my recent article on using a composting toilet in an RV for another solution in your trailer or motorhome.

TMC Electric Marine Toilet, RV Toilet, Boat Toilet, Large Design Bowl, Heavy-Duty Built-In Macerator...
  • LARGE SIZE: Large Design Bowl Heavy-duty Built-In macerator pump. CE Certified, ISO 8846 MARINE (Ignition Protected). Measurements - (A): 14...
  • EASY TO INSTALL: TMC marine toilets can be installed above or below the waterline. The boat toilet base can be rotated to the left, right,...
  • QUIET CLOSE AND EASY TO CLEAN: Deluxe large seat cover. Soft-close lid guaranteeing that your seat will never slam as you put it down. Slow...

Limitations of an RV Macerator Toilet

An RV macerator toilet isn’t limited by many factors, but like any appliance, it does have a few disadvantages that keep RVers from completely switching to macerator toilets.

  • Water Capacity

RV macerator toilets have a specific water capacity that runs their flush cycle. It isn’t a deal breaker if you have a steady stream of water nearby or stock up on freshwater, but it may become a nuisance if your fresh water tank is running low.

  • Motor Malfunction

Since an RV macerator toilet is essentially a motor-powered commode, it could malfunction if your RV house batteries are having issues. Also, the flush cycle may not be as efficient if the pump can’t draw the power it needs from the 12v system.

  • Expensive Recovery

Because an RV macerator toilet is a fairly modern piece of equipment, the engineering is expensive, which means the repair of a malfunctioning part is also expensive. Although it is worth it considering the toilet lasts for 10 to 15 years, the expense can become too much if the toilet isn’t properly maintained.

Here’s a simple fix to your RV toilet that keeps running. My article will help you save money and extend the life of your RV toilet.

Regular Maintenance Steps for an RV Macerator Toilet

Macerator toilets may be one of the best modern plumbing technologies for mobile homes – they are durable, cost-effective and environmentally friendly. Following a few regulatory procedures can extend their life, reduce the likelihood of clogs forming from solid waste, and prevent pungent odors from lingering in the RV.

Here are a few steps you can take to maintain an RV macerator toilet:

  • Make sure the toilet bowl is halfway full before excreting or adding solid waste, it helps the flush cycle run efficiently and grind the waste thoroughly so the toilet doesn’t back up.
  • Never put baby wipes, feminine hygiene products, or packets of tank digester into a macerator toilet. They can damage or clog up the blades and cause an expensive repair. 
  • Pour boiling water in the toilet bowl, as a safe measure, at the end of the night so all potential clogs are broken down. This also helps control bad odor.
  • Take a toilet brush such as the Thetford RV toilet brush and run it lightly around the flush seal (between the ball and seal) to clear up debris and prevent water leakage.
  • Always use a soft bristle toilet brush to clean out the RV macerator toilet. A stiff bristle toilet brush can scratch and damage the valves and bowl.
  • Make sure the disinfectants, cleaners and even the toilet paper you use is septic-safe. Caustic toilet bowl cleaners and bleach will adversely affect the water lines and valves.
  • Don’t forget to add antifreeze after completing the winterization process. It ensures the macerator toilet, valves and water lines do not split when the temperature falls below 30°F.

Frequently Asked Questions

Is an RV macerator toilet the same as an exterior macerator pump?

No, an exterior macerator pump allows you to dump on an incline or uphill when gravity is working against you and a traditional 4 inch RV sewer pipe system will not work. An RV macerator toilet has steel motor blades that grind up waste before pumping it into the RV black tank. 

Installing a macerator pump works great for RVers that are unable to park close to a sewer drain because the ground up slurry can be pumped under pressure a longer distance.

Do macerating toilets work well?

Yes, macerating toilets are easy to install and easily fit in compact spaces. Also, they are durable and last up to 15 years without needing professional maintenance. They are also eco-friendly because they actually dump less water per flush than a normal toilet.

Do I need an RV macerator system?

You need a macerator system if your connection to the sewer or dump station is uphill from your RV’s holding tank connections and gravity can not be used to drain the tanks. 

An external macerator pump is also beneficial when your sewer connection is far from your rig because reducing the solids reduces the likelihood of a blockage in the sewer pipe.

How far can a RV macerator toilet pump?

On average, an RV macerator toilet can pump the discharge upwards of 50 feet. Some toilets can even pump as far as 250 feet. 

It usually depends on what macerator system you have installed and whether it is an exterior macerator pump or an RV macerator toilet — the former is on the output of your black tank and the latter pumps directly into your black water tank.

Can you put a garbage disposal in an RV?

Yes, you can install a garbage disposal in an RV’s sink, but experts don’t recommend it as garbage disposals require the use of lots of water and will deplete your fresh water holding tank quickly. They also consume lots of power to operate and can drain your house batteries quickly if you are not connected to shore power. Also, you may not need it as often as you think.

Brief Summary

RV macerator toilets have gained massive popularity in recent years because they can be installed in any location throughout your rig regardless of black water tank location, and reduce the amount of solids that enter your black tank reducing the likelihood of a clog.

Macerator toilets like the TMC Macerator Toilet are very reliable and by following the regular maintenance steps outlined in the owner’s manual it will work flawlessly for years.


Beau is an electrical engineer with a knack for DIY repair and construction. When he's not tinkering with his projects he's on the road travelling and enjoying an exciting lifestyle with his young family.

Recent Posts