What's With All the Single Function Shower and Tub Faucets?

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StrongEagle

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So... I visit Home Despot, then Lowe's then go online to a couple of outfits. They all sell single function, temperature control faucet valves in all of their sets. What's with this?

For example, I look at a couple of Moen's. They are all sold with the "Posi-Temp" valve, which means it will only control the temperature. But Moen also sells their Moentrol valve which controls both temperature and flow rate... just like all the old single handle shower faucets used to do.

Same thing with Delta... everything in the big box stores and most of the stuff on the websites controls temperature only... no volume control. And yet, like Moen, Delta sells both... single function temperature control and dual function temperature and flow control. As a matter of fact, Delta sells "Multi Choice Universal Valves" where the valve body is the same but the insert gives you one or two function control. Interchangeable Shower Valve with MultiChoice® Technology | Delta Faucet

So... I don't get it... why all of a sudden is my home shower supposed to be like far too many hotel room showers... on/off, temp control but no water flow control?

TIA
 

Geofd

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So... I visit Home Despot, then Lowe's then go online to a couple of outfits. They all sell single function, temperature control faucet valves in all of their sets. What's with this?

For example, I look at a couple of Moen's. They are all sold with the "Posi-Temp" valve, which means it will only control the temperature. But Moen also sells their Moentrol valve which controls both temperature and flow rate... just like all the old single handle shower faucets used to do.

Same thing with Delta... everything in the big box stores and most of the stuff on the websites controls temperature only... no volume control. And yet, like Moen, Delta sells both... single function temperature control and dual function temperature and flow control. As a matter of fact, Delta sells "Multi Choice Universal Valves" where the valve body is the same but the insert gives you one or two function control. Interchangeable Shower Valve with MultiChoice® Technology | Delta Faucet

So... I don't get it... why all of a sudden is my home shower supposed to be like far too many hotel room showers... on/off, temp control but no water flow control?

TIA
I think the reasoning behind no flow control is the shower head by code is only allowed to put out 2.5 gpm
 

fixitron

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It is because plumbing codes were changed to prevent scalding from water that is too hot. That cannot be done with a two (or three) handled shower valve.
 

StrongEagle

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I think the reasoning behind no flow control is the shower head by code is only allowed to put out 2.5 gpm
Thank you! I hadn't thought about that... limited flow means who cares about volume control when the volume is already so low... you turn it on high every time.
 

StrongEagle

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It is because plumbing codes were changed to prevent scalding from water that is too hot. That cannot be done with a two (or three) handled shower valve.
Actually, it can be done with a volume control knob, and all the biggies in the faucet manufacturing business still sell volume control valves... it's just that the kits with valve and trim hardware you find at the big box stores only have the temp control valve in them. You've got to "roll your own" to get something different.
 

Jeff Handy

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Many people want all the volume they can get.

Even having to dig out flow restrictors in the shower head, to get a decent stream of water.

And the trend is towards bigger showerheads which need lots of high flow volume, or even multiple heads that are often starved for enough water.

So nowadays, more volume is usually more better, haha.
 

StrongEagle

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Many people want all the volume they can get.

Even having to dig out flow restrictors in the shower head, to get a decent stream of water.

And the trend is towards bigger showerheads which need lots of high flow volume, or even multiple heads that are often starved for enough water.

So nowadays, more volume is usually more better, haha.
Exactly! Considering a rain shower head, and I always do remove flow restrictors. But, that's also because I tend to turn the water flow off/down, while soaping up.

Ah well... looks like a custom ordering job.
 

Jeff Handy

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You can just add a volume control right at the shower head.
They go between the shower arm and shower head, and their main function is to stop water flow while soaping up, as you do.

The flow is usually still a trickle, not fully off.

Some have a twist lever, some have a push in, push back out type of control.
 

StrongEagle

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You can just add a volume control right at the shower head.
They go between the shower arm and shower head, and their main function is to stop water flow while soaping up, as you do.

The flow is usually still a trickle, not fully off.

Some have a twist lever, some have a push in, push back out type of control.
I'm thinking about going with a Delta valve system that has two handles on the shaft... one for temp, one for flow rate.

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One of their options in their "multi choice universal valve" line - Interchangeable Shower Valve with MultiChoice® Technology | Delta Faucet
 

FishScreener

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The plumbing codes require that all the shower and tub faucets be temperature compensating to avoid the potential for scalds. So, you can‘t have a simple two handle faucet assembly.
 

StrongEagle

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The plumbing codes require that all the shower and tub faucets be temperature compensating to avoid the potential for scalds. So, you can‘t have a simple two handle faucet assembly.
Did you look at the Delta webpage? Or the Moen webpage ( Moen 101 )? All of the valves they sell are "anti-scald", that is, pressure balancing, to deal with sudden changes in pressure, regardless of whether they are single function or dual function. As a matter of fact, my old American Standard fixtures, installed in 1999, that I am getting ready to replace, are also pressure balancing.

So... I think that Geofd's comments about limited flow showerheads, are probably the most reasonable explanation for lack of choices at the big box stores.

And ya know... about the only reason I want to replace these is that I cannot find the trim hardware (escutcheon plate, dial plate, handle, etc)

1596405226018.png
 

StrongEagle

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I put a Moen shower and bath valve into a client's house. Works just fine except he wanted it a tad hotter. I searched high and low, could not get the valve to let any more hot water out. Sort of a pisser.
Was this the PosiTemp valve or the Moentrol? I'm kind leaning towards the Delta Monitor 17 series. They make a "high flow" shower only valve, but still trying to find flow rate specs for it. I like the idea of 2 handles on a single shaft...

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Jeff Handy

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Be aware, many valves come in more supply pipe sizes than just 1/2 inch.

High flow often need 3/4 supply.

Some of the multi head shower rooms might need one inch, I don’t know.
 

StrongEagle

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Be aware, many valves come in more supply pipe sizes than just 1/2 inch.

High flow often need 3/4 supply.

Some of the multi head shower rooms might need one inch, I don’t know.
Man, I'm getting a real education. Will call Delta in the morning about valve and cartridge flow rates.

Reminds me of the guy who walked into home depot paint department one morning. Four of us standing around. The guy says, "Give me a can of tan and a can of white." Little did he know.
 
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