Water Pressure Decrease With "T" Installed

[DW85745]

I installed an undersink filter.
I "T" into the cold water line at the connection point between the kitchen faucet and the cold water supply to the faucet. The "T" part of the line goes to the filter and from the filter to a "separate" faucet ONLY used ON DEMAND to obtain filtered water.

What I noticed was a drop in cold water pressure (volume of water coming out) in the kitchen faucet even though the ON DEMAND filtered water faucet is Off.

Any ideas why?

 

[Reach4]

The answer that seems obvious to me is the tee design is not so good for the purpose. The tee came with the filter? If so, ask the filter maker, since he has probably had that complaint. Maybe he found a solution.

Consider posting a picture of the area including the shut-off valve and the tee.

 

[Sponsor]

 

[hj]

If it is the 'supplied" tee, there are rubber seals at both ends and they could be swollen cutting into the water supply.

 

[Smooky]

If you pushed the pipe in too far on the center part of the Tee, it will restrict the flow.

 

[DW85745]

Thanks for idea guys.
"T" was aftermarket -- did NOT come with Filter unit.
In process of disassembly, so will post if/when find solution.

 

[Jadnashua]

Every time you change direction with a fluid, you create friction to flow. But, since most all kitchen faucets are flow restricted, I'm surprised you noticed a difference if it is a plain T...some special ones could have much bigger internal restrictions than others. Without seeing the T involved, it's hard to say.

 

[Flapper]

Does the T have a straight path through it, or is there something in there?

 

[Plumber69]

Your going lose volume thru everything.

 

[Dj2]

I installed an undersink filter.
I "T" into the cold water line at the connection point between the kitchen faucet and the cold water supply to the faucet. The "T" part of the line goes to the filter and from the filter to a "separate" faucet ONLY used ON DEMAND to obtain filtered water.

What I noticed was a drop in cold water pressure (volume of water coming out) in the kitchen faucet even though the ON DEMAND filtered water faucet is Off.

Any ideas why?

A better way of splitting the water source is to install a T at the wall nipple, then install 2 short nipples with 2 angle stops. One for the cold water side of the faucet and one for the filter.

 

[Jadnashua]

If the T is after the shutoff valve, keep in mind that most of those valves already have internal restriction - i.e., they are not all full-flow, so you have a restriction followed by a potential second restriction.

They do make dual shutoff valves...you might just look into replacing the existing valve with a dual outlet one, or make it two totally individual ones.

 

[Flapper]

A better way of splitting the water source is to install a T at the wall nipple, then install 2 short nipples with 2 angle stops. One for the cold water side of the faucet and one for the filter.

Or replace it with a double valve or a dual-outlet valve

 

[Bluebinky]

Are you sure just the cold side flows less? Perhaps the aerator is full of debris from having things apart.

 

[DW85745]

Turned out the cold water supply line was full of calcium.
Had packed itself so tight had almost restricted all water flow.
Took me awhile to get all the debris out.
Should be good to go for another 30+ years.

If of interest this was 1/2 copper.
Pulled the stop value bonnet and valve, and shoved a "blunted" long awl down the line to help break it up.
Stopped before I hit the 90 degree in the wall. Then hooked up double sided 1/2 PVC FIT
(thankfully these stops had 1/2 outlets) to the stop outlet.. I screwed in a PVC male to water hose adapter to the 1/2 PVC FIT. Reinstalled value and bonnet, turned on water, and let it run. Had to remove bonnet and valve 6 times, repeating process each time, but finally no debris.

Thanks all for your suggestions.

 

[Dj2]

Or replace it with a double valve or a dual-outlet valve

View attachment 35225View attachment 35226

I prefer 2 separate angle stops over one with two outlets. Guess why?

 

[Flapper]

I prefer 2 separate angle stops over one with two outlets. Guess why?

You mean two completely separate stops or two stops in one assembly?
It's so you can shut off the other thing without shutting off the faucet, and vice-versa.