A WC that will not flush

Introduction

Either the pan is blocked — the water rises and falls slowly — or the cistern is not sending water. They are different faults. If the level in the pan rises, do not flush again.

How to tell it apart

The level rises and falls with difficulty: the pan is blocked. Stop before you add more water.

A normal level, an empty cistern, or a flush that does not start: the pan is not blocked. If water enters the pan on its own, that is a cistern that leaks.

Water leaving the shower or the basin while you flush: the stack, not an object in the pan.

Wipes beside the pan, even with “biodegradable” on the pack: look there first. The word on the pack is not a reason to flush them.

Likely causes

• Paper and wipes in the pan.
• Something dropped in.
• A cistern that does not fill: the isolator is shut, or it is not filling.
• A stack return, with other fittings involved.
• A sink plunger used in the WC without a wash: it does not seal, and it moves dirt.

What to do now (€0)

1. If the water rises, do not flush again. Close the isolating valve on the cistern feed, if you can reach it and it turns.
2. If the level is normal and the cistern is empty, do not plunge. Check the isolator. If it leaks into the pan on its own, go to the cistern page.
3. With water in the pan, at a normal level and not rising, use a WC plunger with a flange.
4. Pump steadily. If the level rises, stop at once.
5. Do not push a snake in as a first move.

A small DIY step

1. A WC plunger, with water in the pan, is the small DIY step. A snake marks the glaze and does not open a stack.
2. Wipes do not go in the pan, even when sold as biodegradable, nor cotton buds or sanitary pads.
3. Do not use the sink plunger without washing it.
4. The plunger card shows only if the water is not rising. Do not unbolt the pan.

Mistakes to avoid

• A second flush with the water already high.
• A snake as the first move.
• A chemical cleaner in a pan that will not empty: it stays there.
• The same sink plunger, still dirty.
• Carrying on if water leaves the shower or the basin.

When to call a professional

A plumber now if the water rises, if it leaves other fittings, or if the plunger does not move the level.

Several fittings: the stack. An empty cistern, or one that leaks into the pan with no blockage: the cistern, and a plumber if you do not have the part for that model.

Safety

Do not pour a chemical into a pan that will not empty, and do not add another if one is already there. Do not mix bleach with ammonia or with acids and descalers. If you have already poured some, gloves and air, read the label, stop if you smell fumes.

If water reaches the floor near a socket, do not walk through the water to reach the board. Cut the power at the main only if you can do it dry. Do not open boards, sockets or appliances while they are live: an electrician.

Questions people ask