Thanks and responses/follow-ups
Thanks so much for all for the comments! My replies and follow-up questions below.
- I am only trying to run one head at once. There is a tub faucet, a shower head, and a rain shower head. But I'm only turning on one at any given time. Even so, only a few drops come from the tub faucet, a small trickle from the shower, and low flow from the rain shower. (Pressure in the sink seems fine.)
- I bought a pressure gauge. I can try it at the sink to measure the pressure I'm calling "good/normal". I can attach it to the tub outlet, but I know the pressure there is essentially zero. Or should I be measuring pressure before the water line ever gets into the house?
- If the 3 extra bends to the bathtub faucet (vs. the # of bends to the sink) are very unlikely to cause the problem, then it has to be some sort of obstruction (is that right)?
- So I need to try:
- flushing the lines (hopefully the plumber knows how to do this)
- looking for an obstruction in the diverter or mixer. Can I do this without opening up the wall?