R120 Valve I have good pressure with the cold water but no pressure with hot water

Is the hot water pressure good at other fixtures in the house? I'm guessing your newer valves have a scolding adjustment that is set very low. Check the instructions that came with the valve assembly.

If your washer doesn't go through the washer rinse cycle, the most likely cause is the water valve. What happens is the water valve will stop letting cold water into the washer; therefore, once the washer gets to rinse it will either stop or not do anything during the whole rinse cycle.
This is because when you selected your water temperature, you selected warm/cold or hot/cold. The hot water came in and you didn't notice any problems. When it got to rinse, the cold water the cold water won't come in. Therefore, the washer does nothing.
To check the water valve, first cut the water off and remove the hoses off the back of the washer. Then one at a time point the hoses inside the washer tub and turn the water back on. If you don't have good water pressure, turn the water back off and remove the strainer that should be in one end of the hose. Inspect the strainer to see if it is stopped up, clean it and reinstall it. Now repeat this test. If you have good water pressure now, reinstall hose and your problem is fixed.
If you still don't have good water pressure, the problem is in your house plumbing and you need to call a plumber. If you had good water pressure the first time you performed the test, the water valve is bad and needs replacing.

What happens is the water valve will stop letting cold water into the washer; therefore, once the washer gets to rinse it will either stop or not do anything during the whole rinse cycle.
This is because when you selected your water temperature, you selected warm/cold or hot/cold. The hot water came in and you didn't notice any problems. When it got to rinse, the cold water the cold water won't come in. Therefore, the washer does nothing.
To check the water valve, first cut the water off and remove the hoses off the back of the washer. Then one at a time point the hoses inside the washer tub and turn the water back on. If you don't have good water pressure, turn the water back off and remove the strainer that should be in one end of the hose. Inspect the strainer to see if it is stopped up, clean it and reinstall it. Now repeat this test. If you have good water pressure now, reinstall hose and your problem is fixed.
If you still don't have good water pressure, the problem is in your house plumbing and you need to call a plumber. If you had good water pressure the first time you performed the test, the water valve is bad and needs replacing.

sounds like a bad faucet//only if you had good pressure before it was installed..to cheaply test..take the hot water off from the shutoff valve and spray it into a milk jug to see if theres good flow..then replace the faucet assmbly..dont forget to turn off the shutoff valve first..or you will get a watery surprise!

Could be a chunk of scale in the valve. Need to turn off water supply and take valve apart. If nothing is found, turn water supply on to give line a 'quick' flush and turn back off. If this does not help, you probably have an obstruction somewhere in the hot supply line and a plumber may be needed unless you are handy. Good luck.

it could be the differential in pressure between the cold water from your booster pump and the hot water from your solar water heater . the cold water which feeds your solar heater is probably being reduced in pressure by a pressure reducing valve . so what you need is equal pressure on both your hot and cold water system you could install a pressure reducing valve on the pipe thart feeds your cold taps etc valve set at the same pressure as the one on the solar water heater that would give you a balanced hot and cold water system

You have clog in the water line.
Since all hot water pipes are involved, clog is probably near water heater.

Buy pressure gauge at hardware store that threads onto hose connection.
Brady BTG 100 at Amazon
Picture of gauge

Check outdoor pressure for baseline pressure in your home.
Turn off electricity to hot water heater for an hour or two so there is not scalding water.
Open drain valve on water heater to see if water heater is clogged with sediment.
http://waterheatertimer.org/Water-heater-will-not-drain.html

Put pressure gauge on drain valve and compare with outside pressure.
Open hot water spigot on bathtub and see if tank pressure drops ... if tank pressure drops significantly with bathtub spigot on, then clog is on incoming cold water before tank, and could be on outgoing hot water pipes too.
If tank pressure stays about the same, then clog is on outgoing hot water pipes.

Clog can be sediment caught in cold water shut off valve located above tank. Open and close valve and test pressure again. Take apart incoming cold water pipes above tank and check for sediment. Replace valve. Look at condition of cold water nipple on top of tank.

Sediment caught at hot water elbow near tank.
Sediment can fill up old pipes. Take apart hot water pipes above water heater and see condition.
Look at condition of hot water nipple on top of tank.
You may have to take apart pipes up to first or second elbow.

Pipes can decay at joint where copper pipe connects to galvanized pipe. Check for copper to galvanized connections on cold or hot pipes and replace section of galvanized pipe. Copper pipe will probably be good, the galvanized pipe will deteriorate. Replace copper-to-galvanized joint with 3/4" non-conducting union from hardware store

You need good water pressure on hot for these machines to work, gravity fed systems may not be enough. I had to attach a pump to mine to improve the hot water pressure (UK)
Switch over the inlet pipes ie hot to cold and cold to hot and try filling the machine when switched to fill with hot water, (machine will fill will cold). proving the valve is opening and it is a pressure issue on you hot water.

probably have a kink on how water line feeding valve..if possible to cut drywall bhind tub valve and inspect pipe at bottom plate...moen faucets are equipped w/ anti scald device, pressure balanced (newer models) and this could cause cold water to overwhelm hot water...

Good day,
The washer has a dual valve, Hot and cold. The cold side has failed. Valve needs to be replaced. Very common problem.
Before changing, turn off cold water supply, remove cold water hose at the machines valve, and turn on to check for proper pressure.