Shower Temperature Control

[coolrunnings82]

My house is about 19 years old and ever since I bought it a couple years ago, the showers have had this issue:

Any time someone turns on a faucet anywhere in the house, the water gets either extremely hot or extremely cold. This happens in all 3 showers equally and has become quite a problem. Turn the hot water heater too hot and you've got a safety hazard - too low and your shower is ice.

Does anyone know if there is a faucet that can better regulate this? I have decent enough pressure at the taps and showers and though I'm suspecting this to be a pressure issue, I'm loathe to turn up the pressure on the regulator for fear of causing issues with the polybutylene (sp?) pipe... Any suggestions of possible causes and things I can do to fix this?

 

[Caduceus]

First question. Are the faucets in the showers all single handles or are they two/three handle faucets?
If they are two/three handle faucets, you may need to have thermostatic tempering valves installed at each fixture.
If they are single handle faucets, they may not have thermostatic balancing spools internally or the spools may be damaged or clogged.

 

[coolrunnings82]

They are all single-handle faucets in the showers. How do I go about finding out if they are damaged? They do work to control hot and cold water, however without warning, it will randomly go super hot or super cold. This especially happens if someone turns on a faucet or flushes a toilet anywhere in the house.

 

[johnjh2o]

What you need is to replace the faucet with a balance pressure faucet. What is happening is when someone turns on the cold water while your in the shower it decreases the cold water in the shower causing the shower to become hot. A balance pressure faucet has a spool in it that will decrees the hot the same amount that the cold has been decreased. This will keep the water temperature the same.

John