[MBamburg]

I've read a lot about water pressure problems in showers when other faucets are turned on, however, my issue is more with the water temperature changing. Our house was built in 1999 in the Austin, Texas area - is on city water and is a two story home (both showers are upstairs). The water temperature in the showers change significantly when any other source of water is turned on at the same time. We removed the restrictors (my terminology may be off) from the shower heads and while it helped with the pressure, it did not help with the temperature changes. Have talked to lots of others and find it interesting that some people have problems with either their pressure or temperature changing, both or not at all. Would like to understand the cause of this and what those homes with NO problems have in their plumbing? Also, is there a solution to this problem?? (Other than not turning on any other faucets while showering... with kids in the house, this is frequently forgotten!! ). Thanks for any insight.

[speedball1]

I've read a lot about water pressure problems in showers when other faucets are turned on, however, my issue is more with the water temperature changing. Our house was built in 1999 in the Austin, Texas area - is on city water and is a two story home (both showers are upstairs). The water temperature in the showers change significantly when any other source of water is turned on at the same time. We removed the restrictors (my terminology may be off) from the shower heads and while it helped with the pressure, it did not help with the temperature changes. Have talked to lots of others and find it interesting that some people have problems with either their pressure or temperature changing, both or not at all. Would like to understand the cause of this and what those homes with NO problems have in their plumbing? Also, is there a solution to this problem??? (Other than not turning on any other faucets while showering...with kids in the house, this is frequently forgotten!!!). Thanks for any insight.

I can explain away the mystery with one word, volume. We've all heard about what happens when you flush and someone's in the shower. When both hot and cold are used , as in a shower, and another ficxture on the same branch makes a cold draw it diverts cold water away from the shower to that fixture. Unless there's enough volume to make up the difference the shower suffers.
Our code only allows three fixtures on a 1/2" branch to help with this problem.
I can see two solutions to your case. One would be to increase the branch size. That would involve the hassle of repiping. A more realistic approach would be to change out the shower valves to a pressure monitor or a Posi-Temp shower valves. These valves adjust automatically for pressure and temperature fluctuations. Good luck, Tom

[MBamburg]

Thanks so much!! One last question... I've researched the Posi-Temp valves on the internet and am not totally clear on the parts needed. Can we purchase just the valves themselves and not the trim kits (showerhead, faucet, tub spout) or do we need new trim kits also? I'm fine with our existing hardware and would rather not spend the extra $ if it's not required.

[speedball1]

Thanks so much!!! One last question...I've researched the Posi-Temp valves on the internet and am not totally clear on the parts needed. Can we purchase just the valves themselves and not the trim kits (showerhead, faucet, tub spout) or do we need new trim kits also? I'm fine with our existing hardware and would rather not spend the extra $ if it's not required.

Click on: http://www.homecenter.com/Searchprod...1&pagenumber=2
Look on the right hand side and go down three pictures and find Moen Posi-Temp rough valve ,Model#2590 for $69.71.
Good luck, Tom