Welcome to Just Answer.
Sorry to hear about your problem.
You probably have some loose particles that were in the line that are now blocking something in the faucet. This can occur when the pipes are disturbed or from sediment buildup in the hot water heater.
I would try the following tests:
- Unscrew the aerator at the tip of the faucet and remove, then turn on water to see if pressure is good; if so then take apart and clean the aerator, then reinstall . If pressure is not good...go to next step.
- Shut-off hot water supply under the sink and unscrew the supply line from the faucet; put the end into a bucket and turn valve back on. If pressure is good, the problem is in the faucet/ cartridge and you will need to take the faucet apart to flush out the area where the cartridge sits. If pressure is not good...go to next step.
- Shut-off hot water supply under the sink and unscrew supply line at shut-off valve and attach new supply line; put the end into a bucket and turn valve back on. If pressure is good, the problem is in the supply line between faucet and shut-off valve and replacing it will fix the problem. If pressure is not good...go to next step.
- Shut off main water supply and take hot water shut-off valve apart to inspect the rubber gasket and to see if it possibly is blocking the openings, even when the valve is open. Replace shut-off valve if necessary.
Verify that the hot water heater has been flushed recently. It needs to be flushed regularly, to prevent sediment and build-up from forming, which will eventually make it's way into the plumbing lines. These small particles can block the small openings in a faucet cartridge/ aerator.
Click here for more information on how to flush a hot water heater.
If the supply line is in or near an exterior wall and you are in a cold climate, there is a slight chance that the pipe is frozen. if you have access to the piping, such as from below in a basement, you can feel the pipe for any cold areas and thaw out with a blow dryer. Pipes can freeze without breaking and if this is the case, do your best to better insulate the surrounding areas around this piping to prevent it from happening again.
If you need further help or clarification on this answer, please do not hesitate to reply to this post.
Thanks for asking your question at Just Answer.
Best of Luck, Brian
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