What is an RV Macerator Pump? Ultimate Guide

RV Macerator Pump

A macerator pump, or rv sewer pump, is a device used to liquefy solid waste for easier removal and disposal. The pump pulverizes the solid material as it passes through the macerator before sending it into the wastewater drain line. This allows for fast waste removal systems with less odor than traditional septic systems. The typical macerator system includes a holding tank that allows water to pass through while retaining solids, a macerator pump, and a wastewater drain line that leads from the pump to the outside of the vehicle. This type of system can be used on Rvs, cars, and trucks as well.

Who needs to use an RV macerator pump?

The best reason to use one is because you are in an area that doesn't have sewer hookups. I personally would not use a macerator pump to dispose of human waste on a regular basis. You want the consistency of the material going into the tank to be as close to water as possible. If you add items like food or toilet paper, it will plug up your macerator pump eventually and there is no way to clean it out short of replacing it.

How do they actually work?

A typical RV Macerator Pump takes in water from either a holding tank or directly from the gray water outlet with the discharge line attached leading outside the vehicle (similar to a kitchen sink drain). The pump pulverizes solid waste by breaking down solids into liquid.

Be sure to use a separate tank for your toilet, holding it as long as possible before dumping. This will increase the time between pump cleanings and save you money.

The water coming out of your RV Macerator Pump is called effluent and usually contains solids which are not conducive to drinking or swimming. The large pieces of solid waste are removed from the effluent and deposited into the drain field outside your camper or motorhome. As they say in the business, "Waste Not, Want Not". It will also extend the life of your macerator by keeping it clear of obstructions; i.e., tissue paper, feminine products, etc.

Don't forget to empty any excess grey water before dumping (dump at an angle for good drainage, and use your vacuum hose on the sewer connection if possible).

What do you get with a Macerator Pump?

There is a discharge outlet at the base of the pump; a 2" threaded male fitting with a flat sealing surface. The discharge outlet is where you will connect your sewer hose for regular dumping, and/or your macerator's output. You may also need a reducer to match the diameter of your existing sewer connection (larger than 2 1/2").

There is an inlet port on the side that discharges into your Macerator's tank (through which you drain it periodically).

This unit is self contained, so there are no hoses or wires coming into it from outside sources. It has its own 12 volt DC power cord and fuse holder with current protection included. There is also an inline switch on the AC adapter cable that allows you to turn the unit on and off at will. The AC adapter cable also includes a built in power cord for use, should you need it.

A macerator pump is used to reduce the volume of waste material (human waste and toilet paper), so that they can be pumped through a smaller diameter hose, with less clogging issues. It does this by using an internal spinning impeller inside its tank, which grinds your solid waste up into small pieces before sending it out of the discharge outlet. If you have ever been to a large city public dump station or airport rest room dump station then chances are pretty good that you have seen some type of macerator machine being used in action.

What are the disadvantages of a Macerator Pump?

The big disadvantage of the macerator pump is that they are self-powered, meaning that you will need to have your RV engine running in order to use it. This can be a problem for any older RVs, with the onboard battery's being too weak to power the machine when the rest of your systems are needing a charge. Even though most people do not like having to run their engines just flush their tanks out a bit this still may not be much of a deal breaker.

That is, until you get stuck somewhere and you realize how important that generator was back at home in the garage…:) I know first hand because it happened to me.

How to use a Macerator Pump?

A Macerator pump is easy to use. Follow these steps below to safely use one:

  1. Turn on your RV's generator and let it run for a minute before engaging the macerator pump. If you have another 12V source, get that ready.
  2. Connect the Macerator Pump to your rv's sewer drain.
  3. Connect the pump to the exit hose.
  4. Run hose to sewage connection or to the toilet.
  5. Connect Macerator pump to the 12V source or rv generator.
  6. Remove your RV tank's drain valve.
  7. The Macerator Pump should now be turned on.
  8. Keep it running until you see zero flow.
  9. When the flow reaches zero, the Macerator pump should be turned off.

Backflush to Be Sure

What is backflushing? Backflushing is the process of using a hose to force the water back into your RV's toilet bowl.

The waste from the toilet will flow through your sewer pipe and RV's septic tank, wasting its contents into the holding tank.

If you want to be thorough, check online for how many gallons it takes to fill your sewage tank completely full of liquid. Then balance that amount against how much water went into the toilet before using macerator pump. A gallon or two left behind might be necessary depending on your RV plumbing system.

You'll know when you are finished with backflushing because the backflow will begin again pushing out foul-smelling waste matter until it empties out completely.

RV Macerator Pump Tips & Tricks:

  • Don't use your toilet until you are finished with this.
  • Notice how the outflow of sewage will run into the toilet bowl and fill it up to the brim after running water through macerator pump.
  • "Put a bucket under it just in case there is any leakage." There shouldn't be a big mess, but better safe than sorry.
  • You'll need rubber gloves and possibly a mask if you have allergies or don't like odors.
  • I wouldn't suggest opening windows or turning on furnace/AC while doing this, because all that pressure can potentially blow back at you when opened.
  • If holding tank smells really bad, do this first! The foul smell comes from anaerobic bacteria that forms in tanks full for several weeks without moving.

Odor And The RV Macerator Pump

There is close to zero odor when you use a RV Macerator Pump. As long as the valve is open, the macerator pump maintains 100% fresh air flow into the holding tank.

The sole purpose of the RV Macerator Pump is to chop up the human waste and flush it out of your RV waste holding tank while maintaining all oxygen in that tank at a healthy level for bacteria to break down anything else you put in there (food scraps etc.) If you don't have an odor problem, then using a RV Macerator Pump will not change that.

Is a macerator pump necessary?

Yes, if you want to help break down the waste so it can get out of your RV Holding Tank. The best way to think about this is, "Isn't it better for the RV holding tank if all the waste broke down before I put clean water in?" These are especially helpful if being operated uphill.

How to unclog an rv sewer pump?

  1. First thing to do is to pour some Macerator Pump descaler and toilet cleaner into your toilet bowl.
  2. Next, turn the Macerator pump on for a short period of time, just enough for the descaler to enter it.
  3. Turn your Maceratior pump off and allow to sit for about two hours.
  4. Do not flush your toilet during this period.
Conclusion

You’ve probably heard of macerator pumps, but do you know what they are? Macerators help break down waste by chopping it up into small pieces. If your RV doesn't have a built-in macerator or a holding tank for wastewater, then this is the perfect solution. With our helpful guide on how to use a macerator pump and some tips & tricks for choosing one that's right for you, we hope you found everything you needed to make an informed decision about whether or not this purchase is worth it.

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