Is 3 GPM OK for a valve for shower and tub?
I recently moved into a 2-story house built in 1994. One shower and tub in a bathroom upstairs has very weak water flow (same for cold and hot water). The faucet over sink in the same bath has OK flow/pressure. The water is clear. The tub pipe with the faucet removed is only at 0.5 gallon per minutes.
It is the one knob just turn system (Posi-Temp?). I removed the knob, disc, and cartridge. And after I turned the water to the house back on, the water flow at the valve (with both hot and cold water I guess?) seems OK to me - it is around 3 gallons/minutes. I studied the hole and did not find any stop like the one explained in Visual inspection at the valve show no sign of calcium deposit to me, some one who had never seen such thing before.
Is the flow at 3 gpm OK with both hot and cold water? If so,
- could the pipe/valve be clogged? The water heater that serve the bathroom was recently replaced. But I don't know if the shower/tub water flow was good before that. How can we flush it?
- could it be some stops/shut off somewhere nearby? how can I find out?
Any suggestion/comments? Thanks!
A puzzled mom