Re: single handle lav. Ashfield: cold water flow is fine; hot water flow severly restricted. Have disconnected supply tube and flow is fine into a bucket so it is not a problem with valve or supply tube. What can I do?

If I am reading this right. You have one single handle that controls the temp and flow in your shower, correct? This being the case and you cannot adjust the HOT down enough with the handle. Then my suggestion would be to turn it down at the water heater. If you remove the access door on the side of the unit. There should be either a dial you can turn with a small flathead screwdriver. Or a switch that selects the desired temp. But take into consideration that this will effect ALL water temp throughout your house. Washing machine, Dishwasher, etc..................
There might be one other thing to investigate as well. Look into the cold water supply side at the water heater. It might not be open all the way. Thereby restricting the cold water flow..........:)
Good luck,
Jason

https://www.pfisterfaucets.com/support/faqs/detail/50160000000hi6saac/single-handle-lav-faucet-ashfield-collection-42-t42-842-series--installation-instructions--troubleshooting-guide

You have already checked the two obvious things now make sure the two supply lines from the shut off valves are not kinked or turned it such away as to close off the water flow. If that is ok then there may be some debris in the internal filter screens.

Keep in mind that this faucet design will not put water out at a high pressure if it did it would splash all over the place.

You will need to take the faucet apart and clean it out. If the faucet is a few years old I would just replace the cartridges and be done with it.
When the water heater was replaced the lime build up in the piping was dislodged and I bet the faucet you are having a problem with was the first faucet used after the new water heater was installed.

If water come out the faucet hot line,check if is clogged.For this job you need to disassemble the faucet.

Here is a good PDF source to do it.

If you need more help come back.Post / thumbs / testimonial are welcome!

If you don't have easy access to hot and cold line, where you can disconnect and check for flow to faucet, You can try turning off incoming water supply, remove cartridge, and shut off hot outgoing at water heater, then slowly open incoming (cold) water supply only and see if cold flows from faucet with cartridge removed. At least that will confirm flow faucet, then go from there.

Hi, David pressuming the water flow was good before you put in this new tap, then other than a problem with the tap! have you checked if you have an isolater valve on the pipe work under the unit, if so check that it is fully opened?
Thanks Paul.

I had the same problem. I simply removed the small brass fitting that the water supply screws onto.i removed the screen that is inside the brass fitting. Now the pressure is fine.

Dis-assemble the faucet to get to the valve. The handle comes off and you access the valve from the top, usually by removing a screw on ring.

You will robably find contamination in the hot side of the valve.

You can find instructions on the Moen website.

If you put on the cold and Nothing at all comes out, check the water supply valve to the tub. If it comes out alittle ...the washer probiblly came off and is stuck you will have to remove the valve ,but 1st check that the handle is not stripped ,and that is actually moving the valve to the open position Turn the handle and see if the handle backs out ,like its trying to open.
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