Toilet runs when washing machine

In these cases, the fixture and toilet share common venting. The fixture may even be vented through the toilet drain. Plumbers call this wet venting. When the vents are fully or partially blocked, negative pressure develops in the drains that pulls air from wherever it can.

This happens because water forms an airtight seal as it flows through the pipes, pushing air in front and creating a vacuum behind. Depending on how complete the vent blockage is, the vacuum can be enough to draw air through the toilet and create a gurgling sound. Gurgling is never a good thing to hear, because it signals the possibility that the vacuum will pull water out of the toilet trap and expose the room to sewer gases. So if the toilet keeps running randomly on and off, then you know you have an issue.

This is often referred to as a phantom flush. When you flush the toilet, a number of things happen at once. You pull a lever that lifts the flap. That flap covers the channel that takes water from the tank to the bowl. When it opens, all of the water gushes down to the bowl and into the drainage pipe, then the flap closes to seal the tank once more.

A float in the tank controls the toilet filling valve, which lets water back into the tank after you flush. When enough water fills the tank and the float rises into place, it shuts the toilet filling valve off.

This is all usually over in less than a minute if everything works correctly. If a toilet randomly runs for a few seconds and empties without flushing, it's likely the result of a cracked toilet flapper, the chain being caught, the float needing to be lowered, or the refilling tube needing to be repositioned.

If your toilet randomly runs off and on for a few seconds, it is likely due to a broken flapper. While the flapper is supposed to drop down and re-seal the tank when enough water has gone through, a cracked or decaying flapper will allow water to keep flowing through and run periodically. If you decide that inadequate venting is at least partially responsible for the toilet overflow, check the existing vents. They may be blocked.

Climb on the roof, clear debris from the vent openings and spray water into the opening with a garden hose. If the water backs out, that means there's a blockage. You can usually clear it with a plumbing auger. Even if the vents aren't blocked, they may be undersized or even missing.

If you suspect this, have a licensed plumber inspect your lines so you can proceed in an informed manner. They haven't left an inspection hatch, nor is it as simple as removing a bit of sealant. It looks like I'd have to completely take apart the wall and retile if I want to have a look inside. Modern crap.

Give me a bulk standard 9l siphon flush and ballcock valve anyday Axel , 26 Oct Then it may be what TricklyT says, or your siphon is getting stuck in the open position after flushed. Thanks John. It sounds like a possibility to me too. Joined: 3 Sep Country:. Select the supplier or trade you require, enter your location to begin your search. Please select a service and enter a location to continue You must log in or sign up to reply here. Show Ignored Content. Related Threads.

Replies: 35 Views: Toilet flushes on 3rd attempt j , 7 Feb , in forum: Plumbing and Central Heating.