Toilet fill times

[pakle]

Totally random question: why are my toilet fill times different? I have 3 identical AS Cadet3 toilets bought at the same time with the same factory-set innards including Fluidmaster 400A fill valve. Time from flush to full-fill varies. Here are the config:

Toilet 1 - 1st level and closest to the water heater: 40 sec
Toilet 2 - 2nd level and almost right above Toilet 1: 45 sec
Toilet 3 - 1st level and all the way on the other side of the unit (I'd say 3x as far as Toilet 1): 25 sec

All 3 times are well within acceptable range so why the discrepancy? I get that upstairs would probably take longer but it's almost double the downstairs despite being much closer. Would love to hear the gurus chime in on this slow news day lol.

PS. One of the toilets has since been replaced with a Toto but same fill time.

 

[MicEd69]

The fill times are dependent on the supply pressure and restrictions in the lines to the toilets. The supply pressure will be pretty much the same at each toilet, and the lines to each toilet are probably not going to provide much in the way of restriction of flow to a toilet fill flow rate. But I would guess that the stop valves at each toilet and the flexible lines to the fill valves are having an impact on your fill rates. Mineral buildup inside those components can be surprising and will restrict water flow and therefor the time to refill the tank.

 

[pakle]

The fill times are dependent on the supply pressure and restrictions in the lines to the toilets. The supply pressure will be pretty much the same at each toilet, and the lines to each toilet are probably not going to provide much in the way of restriction of flow to a toilet fill flow rate. But I would guess that the stop valves at each toilet and the flexible lines to the fill valves are having an impact on your fill rates. Mineral buildup inside those components can be surprising and will restrict water flow and therefor the time to refill the tank.

Thanks! I didn't think about the lines and stops. They were all replaced at the same time a few years prior to the toilets. However the 25 sec toilet has a newer supply line because I replaced it when I changed the bidet attachment on it. So maybe that one doesn't have as much buildup as the others.

I guess I should have had the plumber replace the supply line on the toilet recently swapped out with a Toto - that's the 45 sec toilet.