Single handle shower valve.. can't get any hot

Adjustment is usually on the valve assembly. Take off the big round trim ring and you will find the adjustment on the valve assembly or in the valve stem.

Contact glacier bay to get a replacement control/handle assembly. Usually their customer service department is good at replacing the parts under warranty

You should have individual cold & hot water supply shut-offs in your basement for your tub/shower; if not, now's the time to install them.

If I could be of further assistance, please don't hesitate to ask.

If I understand correctly, you have single handled shower faucet.
Normally there is a wait for hot water to arrive at faucet.
But now hot water is already at shower faucet.

Single handled faucets have a mixing area inside valve where hot and cold come together before going into sink.
This mixing valve can have crossover where the hot and cold can pass through to each other even when faucet handle is off. When single handle faucets get old, this can happen.
How it happens:
For example another faucet is turned on inside house, and pressure differential between hot and cold causes hot water at shower handle to pass through mixing area and into cold water line.
So if another faucet has been run, then that lets hot flow to faulty single handled shower faucet.
To confirm this is the problem: turn on other faucet and put ear against shower faucet to listen for moving water.
This condition may also signal there is a water leak.
The problem is not harmful, but will draw cold water into water heater each time, and is energy wasteful.
Replace faucet or have plumber repair problem.

u need to adjust the scald protector all single handle units are shipped in cold position for safety reasons if have paper work for handle it explains how to adjust if not unscrew handle and remove on handle / valve stem will see a red and a blue plastic clips pull back clips and turn slightly and push back do this till desired hot and cold setting are to your liking replace handle and your done

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.

when it is sold the anti-scold is set at cold to protect the buyer -the piece with the groves on it is the stem their should be two plastic clips a red and blue that slid over it these clips are the adjustment -also give pegasus a call they have an 800 number to assist u or home depot the carry the brand

Those new faucets generally have a lower water pressure due to legislation passed in 2007 that reduced that maximum allowable gpm (gallons per minute). I hate to tell anyone this but there is little if anything you can do. First of all, make sure the shut-off valves are open completely. I know that sounds elementary but I've seen it a bunch of times.

Also check to see if the aerator is blocked with a bit of debris.....unlikely if the flow is uniform but still an easy fix.

Hope I didn't break your spirit too much....

Hello, first if any water supply hot or cold is turned off, you will experience trickling as you mention. You must have both cold and hot in order to adjust the temperature on your valve. if you had a plumber intall this unit you should ask him to adjust it. Otherwise here is how:
Rotate the handle counterclockwise to stop and let water run till cold water is purged, check
temperature. Rotate handle to off, remove handle parts (see Disassembly in your manual) and temperature limit stop, rotate clockwise to decrease and counterclockwise to increase maximum hot water temperature, reinstall temperature limit stop and handle (TIP: Do not screw handle in until desired maximum temperature is achieved) Repeat steps until desired maximum
temperature is achieved

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