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An upflush toilet like Saniflo is a great option when installing a bathroom in a location below the sewer line, such as a basement. As the name suggests, an upflush toilet is designed to flush waste upward. Although some homeowners think that a Saniflo toilet is a recipe for disaster, most models can accomplish the task efficiently and without a hitch. An upflush toilet typically features a macerator that turns solids into a slurry and an electric pump that pushes the waste up and away to the sewer line through a 3/4- or 1-inch pipe. Its discharge system is totally different from a gravity-fed toilet system and is often the source of most Saniflo toilet problems.

Common problems with Saniflo toilets can include clogs or blockages in the macerator unit, pump failures, and issues with the flushing mechanism. These toilets rely on a macerator to grind waste and a pump to push it up and into the existing plumbing system, so any malfunction in these components can lead to problems. Additionally, improper installation or insufficient maintenance can exacerbate these issues. Regularly cleaning and avoiding flushing items that can’t be broken down easily (like sanitary products or excessive toilet paper) can help prevent many common problems with Saniflo toilets.

How a Saniflo Toilet Works

An upflush toilet like Saniflo looks like a conventional toilet but has a large plastic box behind it instead of a tank. This box is where the macerator, the pump, and the pressure-sensitive switches and membranes are, which tell the pump when to start and when to stop working. On the box’s exterior, there is a 1/2-inch vent pipe and a 3/4- or 1-inch discharge pipe, both connected by special fittings. It also has an electric power cord, a 1/2-inch water supply pipe, and drain connections for the shower and sink, depending on the plumbing design.

When you flush the toilet, all the bowl contents go into a small tank, and the macerator starts working automatically to grind the waste. Once the slurry level in the toilet tank reaches a predetermined amount, the pump comes on and transfers the contents to the sewer line via the discharge pipe. An upflush toilet also features a check valve on the discharge pipe to ensure nothing can return to the toilet tank once the pump ejects it.

Common Saniflo Toilet Problems and How to Fix Them

The macerator in a toilet is like a sharp-edged knife that keeps turning whenever you flush the toilet. If you try to flush something it can’t withstand, it will get stuck. If something blocks your toilet or the pump, it may cause your toilet to keep flushing, and you won’t be able to stop it from doing that. If the toilet keeps flushing water that it isn’t supposed to, unplug it and remove any obstruction using tongs. If there’s an obstruction on the pump, you’ll need to remove the impeller from the toilet to inspect it and service it.

Sometimes, debris may get stuck in the discharge pipe, and the pump may operate continuously without ever emptying the tank. It may take a professional plumber to find and clear an obstruction. If the pipes are frozen, the system should continue to operate normally when the thermostat is set to go up.

When you have a toilet that acts as a drain for extra bathroom fixtures and wastewater backs out of the drain pipes, it may mean the pump isn’t working properly, or the pipes are blocked. Check the power outlet and the circuit breakers first because one of them may have tripped. Listen for strange noises that the pump is making, indicating that the pump needs service. You should check the microswitch and membrane that measure the level of the water and tell the pump when to come on to start pumping water if there are any signs that these devices are failing.

Here are some of the most common upflush toilet problems and how to best fix them:

1. The Toilet Smells Terribly

It is normal for the toilet tank to get dirty over time or when there is only a very small amount of water in it. The minerals in the water will mix with the waste and cause an unpleasant odor. You should descale your upflush toilet every few years to prevent this issue. Always follow the manufacturer’s instructions on how to descale your upflush toilet. For most brands, you can fill the tank with vinegar, allow it to stand for a few hours, and then flush it away.

How to Fix

Use a high-quality toilet descaler to clean the pump. Avoid using harsh cleaning chemicals or bleach. Avoid using ordinary cleaning chemicals or bleach to clean the pump because they can damage pump parts.

2. The Macerating Toilet Keeps Running And Doesn’t Switch Off

Sometimes, macerating pumps simply fail to shut off when they should. Sometimes, when it happens, the pump can continue to flush even when the macerator is clear. It is not easy to diagnose problems that cause the pump to stop working altogether. It could be caused by one problem or a combination of problems, such as:

• A blocked macerator or pump
• A blocked waste pipe leading to the drain system
• Damaged pump’s rubber membrane
• Faulty microswitch

How to Fix

• Blockage in the macerator – Turn off the power to your macerating toilet and try to remove any blocks that might be blocking the pump. If there is a blockage in the unit, removing it with a pair of narrow-nosed pliers should be sufficient to clear it.
• Blockage in the impellers of the flush toilet – Look for any obstructions in the pump’s impellers and get rid of them. If you are unable to access the pump, try lifting the motor from the unit and turning the unit upside down to access the pump.
• Blockage in the return valve for the waste outlet – Check if the return valve is blocked, as this may cause the waste to be returned to the pump when it hits the blockage. Normally, a problem is caused by a stuck lid being in the waste outlet and a clogged return valve. To clear this, use pliers to remove the outer cover from the waste outlet and unclog the return valve. Sometimes, the return valve is damaged and needs to be replaced.
• Microswitch doesn’t fire properly – Another common problem with flush toilets is that the microswitch doesn’t fire properly when it is supposed to. Solid waste can get stuck between the switch and the bottom of the tank, causing the switch to think that the tank is full and that it is necessary to flush it. If this happens, you will need to empty the tank manually and restart the pump.
• Damaged rubber membrane – If your unit has a damaged rubber membrane, it can cause endless flushing. It is basically a rubber sheet that water presses against when it is rushing to start up the pump. If the rubber membrane becomes damaged or loses its rubber seal, wastewater will eventually cause the switch to fail. If you have a macerating toilet that is still under warranty, it should be possible to get a replacement toilet from the manufacturer.

3. The Upflush Toilet Frequently Trips The Electricals

Macerating pumps use electricity to break down waste and then pump it up to your septic tank or sewer line. If your upflush toilet continually trips the electrical supply, the system could be severely damaged, and you should take great care to fix it. First, turn off the mains power supply and inspect the pump to see if there are any damages. In many cases, this means that the motor itself may be faulty. If the seal on the motor is damaged, the unit may be flooded, and any damage to the motor will cause a short circuit in the pump’s electronics.

How to Fix

Have a qualified electrician check the electrical connections.

4. The Macerating Toilet Is Foaming Up

If the microswitch on your toilet gets too old, it will not cause your toilet to start until the tank becomes full. When a microswitch is activated, the spinning mechanism causes the water to flow through the vents into the toilet.

How to Fix It?

Try first changing the protective rubber that protects the microswitch. As the rubber on the switch gradually degrades, it becomes harder to push it to activate it. Nevertheless, if the problem persists even after you replace the rubber insulator that protects the microswitch, it may be necessary to replace the entire microswitch.

5. The Toilet Keeps Blocking And Backing Up

If you frequently find that your toilet will not flush properly and the water from the toilet is often backing up to the shower basin, the internal unit or waste pipe is likely blocked. Blockages are caused when a waste pipe is installed incorrectly. Generally, pipes should be installed at a 45-degree angle to ensure that waste is properly pumped out of the pump and doesn’t flow back to the tank.

How to Fix 

This problem is commonly caused by a blockage in one of the waste pipes, limiting the flow of wastewater from the pump to the waste line. First, try to remove any rust from the water tank or macerator. If that doesn’t work, the blockage may be in your waste pipe. You will need to hire a professional plumber to inspect and remove the blockage. It is important to ensure that all the pipes are installed at an angle of 45 degrees.

6. The Macerator Is Running But Not Pumping Out

The problem often arises when the waste pipe becomes frozen, especially in winter. 

How to Fix 

First, turn off the waste management unit and try to remove some of the waste manually, especially if it is very dangerous to overflow the waste pipe. Put hot water on some hot towels and stretch them along the length of the waste pipe to help you defrost the waste and flush the water out.

7. The Toilet Is Vibrating Loudly

If the macerator makes a vibrating noise whenever you flush your toilet, then some foreign objects could be caught in the macerator blade. You can fix the issue yourself by getting dirty and turning the blade by hand or calling a professional plumber.

How to Fix

Turn off the power to the pump by turning off the main supply. Carefully open and remove the cover and check inside the macerator if there is any object tangling the blade. Use a pair of thin-blade pliers to carefully pry off the obstruction by slowly turning the blade clockwise.

8. The Macerator Keeps Firing Randomly

In case the pump keeps firing randomly during the day or night, even when no one is pressing the push button, the microswitch may be faulty. This issue could be caused by a dysfunctional rubber membrane that triggers the switching mechanism, or there could be solid waste lodged between the tank floor and the switch.

How to Fix

Check if there is any foreign object between the switch and the tank floor. It can cause the switch to think that the tank is full and cause the pump to start flushing the tank. Fix the problem by removing solid waste near the microswitch and restarting the pump.

If the rubber membrane that triggers the switch wears out or is lost its seal, wastewater can enter the switch and cause it to malfunction. If this happens, you will have to replace the rubber membrane and the switch. Also, check if the button is stuck in the wrong position.

FAQs About Saniflo Toilet Problems

Can you plunge a Saniflo toilet?

A waste macerator breaks down solid waste into tiny pieces that are small enough that they will travel in your other waste pipes. If you get a clog or blockage in your upflush toilet, you cannot simply plunge it to unblock the toilet, or you may damage the pump/macerator. Take apart the toilet, and clean the parts that are inside it.

What can go wrong with a macerator toilet?

Macerator toilets are quiet and powerful, but there are problems that can arise. They can stop working when foreign objects tangle the macerator blades or when the waste pipe becomes blocked.

How do you maintain an Upflush toilet?

Pour two to three cups of non-acidic toilet bowl cleaner down the toilet. Allow it to sit there for at least two to three hours. During this time, the toilet bowl cleaner dissolves any stubborn stains and particles in the toilet. Finally, flush the toilet to clear the waste and any debris.

How long do upflush toilets last?

An upflush toilet is made up of a macerator system and a pump unit. Generally, upflush toilets are very durable and last a long time. However, toilets made from recycled plastic last about ten years before the mechanical components are replaced.

How do you clear a Saniflo blockage?

Simply take some sharp-edged pliers to break open any obstruction in the return valve. If the valve that returns water to the pump is faulty, it will need to be replaced.