We have just installed a Pegasus Thermostatic Bath Faucet. Series K800 148 567P. The hot water comes out as only a trickle. Cold water comes out fast. Is there an a way to adjust this?

Pegasus tub and shower thermostatic faucet handle stripped

I have a similar problem in a house I just moved into. It's clearly not an issue with the temperature settings because I adjusted those and it hasn't fixed the problem. Pressure is low and it's only hot water, which leads me to believe the cold water isn't making it to the faucet for some reason. Have you figured out a solution? I'm searching all over and can't find anything. It's maddening. Thanks.
Bob

single water handles are often put back in 180 degrees off, remove the shaft and turn it over

If this is a Moen posi temp valve you may need to adjust the temperature limit stop. It is located under the handle. Usualy a plastic peice with grooves in it so it fits in another peice in the valve. If I remember right you pull this peice out and turn it counter clockwise to get more hot water. Do this in small increments and reassemble and test. I hope this helps.

Probably some pipe rust clogged the exit.
If u have pretty low pressure on one or both, hot and cold water, try keep force closed by hand the water exit at shower pipe, then start both cold and warm water gradually as much as u can keep it closed with the hand.
The pressure of the water will try "escape thru the clogged pipe and hopefully unlock that debris or rust!
The hot water pressure going back thru the cold water pipe might unclog that debris.
Just a simple fix which many times works as a charm..
Otherwise if this is not fixing, try close both water from main service valve.
Then unscrew the secondary shower valves and manually clean them or replace if very damaged.

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.

remove handle , unthread collar , same with chrome body base . make sure water is turned off from valve

grohe is a faucet all by itself ,,, I would recomend to have you call there repair dept. and explain this to them, you said you put in the new cartridge and thats about all there is to it, when you put on the handle make sure it is not over tightened, sometimes it pulls on the cartridge and makes it come on by itself good luck

The antiscald device needs to be adjusted. It's behind the escucheon and determines the amount of hot water flow.

Usualy when this happens you need to change out the cartrage that controls the water. try to find your faucet at the link below. If you find it click on it scrol down and you can view the manual. It will terr you how to change it out.

http://www.deltafaucet.com/bath/index.html#tubshower_

Good Luck