niagara stealth toilet problems

4 Niagara Stealth Toilet Problems & Solutions

The quiet flushing of Niagara Stealth toilets is the main reason their popularity is on the rise. The manufacturers designed the toilet tanks and installed valves to prevent the noise from escaping into your bathroom. However, you should look out for Niagara Stealth toilet problems.

The common Niagara Stealth toilet problems include failure to flush, blocked vents, continuous running, and poor flushing. Troubleshoot these issues first if you are experiencing problems with your toilet.

Niagara Stealth toilet problems are pretty annoying, so it is understandable to feel frustrated. Fortunately, you can DIY most of them.

This post discusses the various issues, their possible causes and recommended fixes. 

Niagara Stealth Toilet Problems (Quick Fix)

The table below gives an overview of Niagara Stealth toilet problems and their corresponding fixes. 

Problem Possible Causes Recommended Fix
1. Toilet won’t flush
  • Air gaps from the toilet tank
  • Clogged 400-A fluid master valve
  • Low water levels
Adjust the water level

Replace the fluid master valve

2. Blocked vents
  • Foreign materials, such as tissue paper, menstrual materials, e.t.c
Snake or plunge the toilet.
3. Poor flushing
  • Low water levels in the toilet tank
  • Clogged waste pipes, jets, and air transfer tube. 
Remove the clogs

Adjust the water level

4. Toilet keeps running
  • Leaking
  • A shorter or longer rod
  • Faulty float cup arm pin and float cup valve
Adjust the rod


1. Niagara Stealth Toilet Won’t Flush

Even though Niagara Stealth gives powerful flushes with little water, it might stop flushing for some reason. The problem could stem from air gaps caused by water draining from the tank at five-minute intervals. 

The toilet can also fail to flush because of low water levels. The water level in the toilet tank goes down, and the tank doesn’t fill up even if it’s connected to the continuous water supply. 

Furthermore, your Niagara Stealth may fail to flush as a result of a clogged 400-A fluid master valve. The fluid master valve performs flushing tasks and ensures the fixture gives strong flushes to push waste down the drain. 

Therefore, any disturbance with the valve will stop your silent toilet from flushing. 


  • Cut off the water supply and observe how long it takes for the water level in the tank to drop. 
  • If you have an older version, consider replacing the flapper seal. 
  • Replace the fluid master valve. 

2. Blocked Vents

Toilet paper, hair, menstrual products, and other foreign objects can clog your toilet vents. You can check for blockage by pouring a bucket of water into the Niagara Stealth toilet bowl and observing how it drains. If the toilet takes a long time to drain, it means you have a clogged vent. 

The magnificent water-efficient toilets were designed to drain 0.8 kg of waste with each flush. Tissue paper and other foreign items could be ultralight but gain considerable weight (even four times their original weight) after absorbing water. 

This could create more problems in the sewer systems, such as clogging. It also explains why some professionals caution against using, dumping, and leaving toilet tissue without flushing them. 

If possible, they suggest it would be advantageous if you didn’t throw tissues into Niagara Stealth toilets and dumped them in baskets instead. It will save you from additional plumbing costs. 


  • You can either snake or plunge the toilet. Adjust the augur to get past the trap as you snake the fixture. 
  • Modify the conventional augur so the drop head can cover the distance of the trap. 
  • Stretch the coil beneath the drop head by an inch to give the drop head more flexibility to navigate tighter angles. 
  • Push the snake’s drop pin through the toilet until you hit a clog. 
  • Twist the snake and force it through the clog until the water flows. 
  • Next, remove the snake carefully to avoid causing extra damage to the flushing system or other parts of the toilet. 

3. Niagara Stealth Toilet Poor Flushing Problems

It stems from sunken water levels in the toilet bowl and clogged waste pipes and jets. Even though Niagara Stealth uses little water to flush waste, it could cause it to run continuously and deliver weak flushes. 

In addition, a clogged air transfer tube will also result in flushing problems. Manual cleaning could misalign the tubing and create more problems. 


  • Examine whether the toilet tank is inclined to the wall. The tank’s angling implies the disconnection of the air tube.
  • After identifying the problem, ensure the tank has enough water. 
  • Check the BSB valve sign (which shows the waterline) and adjust the fill valve using a Phillips screwdriver. 
  • Turn the screw connected to the float clockwise or counterclockwise to adjust the water level. 
  • Press the stealth flush button to be sure it’s working. 

If the air transfer tube is the source of the problem, do the following:

  • Remove the toilet tank. 
  • Pour plenty of hot water and direct it to the tube. 
  • The hot water will clear the blockage and restore normalcy. 

See also Offset toilet flange problems

4. Niagara Stealth Toilet Keeps Running

A continuous running toilet is a common problem with Niagara Stealth models. A continuous running toilet also signifies potential leaking, float cup arm pin, and float cup valve problems. 

Pressing the flush button 1/16 to 1/8 inch inward can help determine whether and why your fixture won’t stop running. A shorter rod will make you feel resistance after a longer period, while a longer rod will do the opposite. 


  • Take off the toilet lid to expose the black adjustment screw at the bottom of the long rod. 
  • Turn the rod clockwise to make it shorter and counterclockwise to make it longer, based on what you noticed after pressing the flush button. 
  • If the toilet is still running, check for blockages in the float cup. 
  • Hand-lift the float cup if it is facing down, then check whether you solved the problem. 
  • If not, detach the cap from the top of the float cup arm pin and float cup valve, which gives you access to another cap. 
  • Press it firmly, then turn it counterclockwise to remove it. 
  • Wash the rubber seal, reassemble the fixture, and test it again for continuous running. 
  • If the procedure doesn’t get the job done, consider changing the float cup valve. 

Is Niagara Stealth a Good Toilet?

Despite the problems discussed above, Niagara Stealth is still a decent toilet. It comes in single- and dual-flush models that are water-saving. 

The single flush uses 0.8 gallons of water per flush (GPF). On the other hand, the dual-flush has a smaller flushing that utilizes 0.5 gallons per flush and a bigger flushing that uses 0.8 GPF. 

An exciting thing about Niagara Stealth toilets is their ability to use little water to deliver powerful flushes that push the waste down the drain. It also features a 400-A fluidmaster within the tank, which alleviates leak concerns and performs all flushing duties. 

Additionally, you’ll observe that Niagara Stealth pulled away from traditional flapper designs to create modern flapper-free flush valves. Old toilet models have flappers that slow down water exchange, which is compensated for by the 360-degree valve in Niagara Stealths. 

See also Proflo toilet problems

Final Remarks on Niagara Stealth Toilet Problems

Niagara Stealth toilets are efficient, affordable, and noise-free fixtures with premium components. However, they are not flawless since they have problems like continuous running, poor flushing, and blocked vents. 

Fortunately, this easy-to-read piece has discussed the problems and given corresponding solutions for every defect. In cases of uncertainty or if the problems persist, contact a plumber.

See also Aquasource toilet problems

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