Why is there no hot water in the kitchen after flushing our water heater?

Question

My husband and I recently moved into a new house that has two water heaters. One is gas and supplies the main portion of the house, the second is electric and (as far as we can tell) only supplies the extra bathroom added in our garage conversion. We flushed the gas heater today and now have no pressure at our kitchen sink, but only when hot water is turned on. All bathroom faucets and our laundry machine are working fine.

We took the following steps:

1. turned off gas
2. turned off water
3. opened the pressure relief valve
4. opened the drain valve
5. let water drain
6. closed drain valve
7. closed pressure valve
8. refilled heater
9. turned on gas

Our only guess currently is that somehow the pipe to the kitchen clogged, but we haven't had a chance to try dismantling anything yet.

Answer 1

First thing to check is the faucet aerator. You're probably right about kicking sediment up and clogging something, if you're lucky its just the aerator. It'd take a big piece or a lot of sediment to completely clog a 1/2"-3/4" pipe.

If it's not the aerator, and it's just a single faucet, you have to work backwards starting with the supply lines connecting the faucet to the shut-off valve, all the way back to the water heater.

Answer 2

Ancient thread, but since I couldn't find this info anywhere else, I'm going to post to this.

Since it's only the hot water that isn't flowing, the problem isn't the aerator, it's almost certainly the cartridge (the device connected to the faucet handle that mixes the hot and cold water). That has very small openings that clog/jam easily. You may want to download the parts/maintenance manual for your faucet for instructions on removing it. Before you pull the cartridge, you want to remove any other downstream constriction points that remaining sediment could get caught in. If your faucet has a pull-out hose, that probably has a disconnect fitting with a back-flow prevention valve, and whatever clogged the cartridge has a good chance of getting stuck in that too, so disconnect the hose, and set a pan or bucket for it to drain into when you flush the faucet. Otherwise, it should just be the aerator, so pull that off. Now you can turn off the water to the faucet, remove and clean the cartridge and reassemble (you may want to add some cartridge grease). Turn the water back on, flush the faucet, then reconnect the hose or aerator.

If you don't mind making a little mess, it would also save you a lot of potential hassle from more sediment re-clogging the cartridge if you briefly turn the hot water back on while the cartridge is pulled out. Even if you do this, I'd still pull the other constriction points and clean them, since they may have already gotten some sediment before the cartridge jammed.