I have an older single handle Delta shower valve, and I am only able to get good water pressure on cold water (which is opposite of the normal right hand). Can you suggest a solution?

If your new Delta single handle shower valve won't shut off, it could be due to an issue with the valve itself or with the installation. Some possible causes include a misaligned handle, debris in the valve body, or a faulty cartridge. It is best to check the installation instructions and ensure that everything is properly seated and aligned. If that does not solve the issue, you may need to contact Delta customer service for further assistance or consider hiring a plumber to diagnose and fix the problem.

It is more that likely the valve in the stem of your fixture, I'm assuming this is a single handle faucet. If you can replace the valve, you will cure your problem. I am giving you a link to how to adjust the hot water temp.

http://www.ehow.com/how_6531012_adjust-anti_scald-setting-delta-faucets.html

no but you will get a cross conection problem

Before you do that remove shower head and see if you have flow without the head. The shower heads clog much more easily than the diverter valve

On a single lever shower handle, when the handle is pointing straight down the water is off. The handle will then rotate 270 degrees to the right through cold - warm - hot. What has happened is when you took the other handle off the new handle didn't go into the same position as the old one. So now when the handle stops at the down position the valve is still open probable running cold water. The fix is to take the handle back off. Rotate the valve into the off position so that water stops flowing and reinstall the handle pointing down. Now when you rotate the handle to the right you will get cold then warm then hot at 270 degrees and back to off when the handle is pointing back straight down. If you are still having problems please let me know and we will examine it a little closer.

That is a graduated water mixer valve, and it sometimes has a little white water restrictor blocking flow from your hot water port. See if that was left in by removing the handle with all water shut off to the valve and reattach then try again. This can also happen if you have a tankless water heater because pressure controls heat. Typically a Tankless water heater system will require little, to no cold water to your bathtub valve because of the heavy water flow at the tap. Remember, flow equals temperature. Less flow = more heat, more flow = less heat.

Based on your description it sounds like the pressure balancing valve could be gunked up with particulate from your well or just worn out. If your water is not filtered to that shower I would lean more towards particulate. Try to remove the cartridge and take it to a plumbing parts store for a match-up since Delta makes several cartridges and you want to get it right the first time.

bad faucet...get new at lowes or home depot

replacing just the handle cannot fix the leak and common sense should tell you that.... try turning off the water to the diverter (thru access panel on opposit wall or main water valve for the home) and then replacing the stem or cartridge inside the diverter -- this is what controls water temp, pressure, and is responsible for any leaks you may have...

well they should be same size but unless you getting more of one then other then sound like mixing valve is not mixing. do have 3/4 hook up to mixing valve? you only need 1/2" to valve.