Repair when Flushing

How to check your toilet's flush volume

Knowing how much your toilet flushes and which valves to use with them can be a complicated business. This article will help determine what valves are best used with your toilets. The easiest way to determine a toilet gallon per flush volume and which valve to use is by looking at the date of the toilet and looking at your toilets flush valve system. Use this date method to find the parts recommended.

  • Pre – 1994
  • 1994 – Present
  • 2005 – Present (HET- High Efficiency Toilets)

Pre-1994 Toilets Water Saving and older toilets:

Toilets that date prior to 1994 fall in to two main flush volumes: 5-7 gallon per flush (gpf) and 3.5 gallons per flush (gpf). In these toilets, Fluidmaster recommends using our Standard or Leak Prevention Fill Valves (400A or 400A with Brass Shank  or 400LSR) and a 2 inch (Non-Adjustable) Flappers (models include 500, 501, 503, 504).

1994  to 2006 Toilets:

Toilets that are dated 1994 to present time fall into two main flush volumes, 1.6 and 1.28 gallons per flush.

In these toilets, Fluidmaster recommends using both our High Performance Fill Valves (Model 400AH) or (Model 400H) our PerforMax® and Water Savings (Adjustable) Flappers both in 2 and 3 inch (sizing) categories (models include 502, 5051 and 5403).

2005 – Present (High Efficiency Toilets):

Toilets that are dated 2005 to present time fall into two main flush volumes, 1.28 and lower gallons per flush.

In these toilets,  Fluidmaster recommends using both our High Performance Fill Valves (Model 400AH) or (Model 400H)–  PerforMax® and Water Savings (Adjustable) Flappers – both 2 and 3 inch (sizing) categories –  3 inch Flush Valve (model 540AKR).

HET is an abbreviation for High Efficiency Toilet. These toilets have flush volumes that are less than the standard 1.6 gallon per flush toilet. These toilets need a higher refill rate when refilling the toilet bowl and may come with a larger than standard 2 inch flush valve drain.

Flush valves can be designed as Dual Flush, Tower Flush, 2 inch and 3 inch Flush Valve Drains.

  • Dual Flush valves can alternate the flush volume from a full flush (standard flush volume of 1.6 or less) to a partial flush (less than standard full flush). Fluidmaster  has a Dual Flush which converts “any” standard flush to an alternating flush using our dual flush technology (models 550DFRK & 550DFR)
  • Tower flush valves are valves that normally are 1 piece in design and the entire flush valve drain lifts up to release the water.
  • 2 inch and 3 inch Flush Valves are valves that flush using a flapper valve to release the water. The designation 2 inch and 3 inch describe the drain opening along with the corresponding size of the flapper that covers the drain opening. If you are unsure whether you have a 2″ or 3″ flush valve, please click here: Determine size of flush valve

To see list of valves or kits that we recommend follow these links:

Fill Valves

Flappers

Repair Kits

Flush Valves

If you need to replace any of the toilet parts, why not get Fluidmaster’s Everything Kit includes everything you need to fix your toilet in one purchase?

If you are in the U.S. and have a 2″ flush valve toilet, we recommend the 2″ Everything Kit

If you are in the U.S. and have a 3″ flush valve toilet, we recommend the 3″ Everything Kit

If you are in Canada and have a 2″ flush valve toilet, we recommend the 2″ Everything Kit

If you are in Canada and have a 3″ flush valve toilet, we recommend both the 540AKR Flush Valve and the 400H Fill Valve

To download our free guide to fix common toilet problems please click here: Fluidmaster Toilet Repair Guide