We have a single handle Moen kitchen faucet with the built in sprayer in the faucet. No hot water will come out and no water pressure in the hot position. Any ideas?

I had the same problem and here is what I did.



1) Took off the aerator at the tip of the handle. The was some debris in the screen. I cleaned that out, soaked it in white vinegar for a while (to dissolve hard water deposits) and re-installed it. Not the problem.

2) Took off the handle itself right where it meets the flexible hose. There is a screen there also (remember this location for later). There was some of the same debris in this screen that looked like tiny pieces of rubber and some sand. Cleaned this out and replaced. Not the problem.

3) After insuring that the hot water supply line was turned off at the valve under the sink, I disconnected the hot water supply line under the sink right where it goes into the valve itself. Be certain to have a water catch-basin and some towels to capture any water that will surely come out with this maneuver. I then turned on the valve (with the hot water supply line disconnected) and found out INSTANTLY that the hot water pressure was just fine up to the valve! The water came out at something approaching the speed of light! The water catch basin became very important at this juncture! So, the problem was obviously somewhere between the handle and the valve (between the shut off valve and the faucet itself).

4) My set-up had a two-foot piece of the "J-shaped" copper tubing that ran from the valve under the sink up to another connection just before it went through the countertop and on to the faucet. I took that piece off and found that this was completely clear. So, I knew that the problem was somewhere from the faucet handle to the connection just below the countertop.

5) At this point, I took a section of "weed-whacker" plastic line and used it as a fishtape to wiggle and scrape around and was able to dislodge many more pieces of that black rubber.

6) Now, it got interesting. Remember that location in #2...right where the handle meets the flexible hose? I took the handle off again and replaced the screen-washer with a DIME. I then screwed the handle back on to the flexible hose. The idea here is to prevent any water from getting out of the handle....the dime seals it right up. Then, I turned on the cold water (remembering to have catch basins and towels properly placed). When you do this, the cold water cannot get out of the faucet (there is a dime in the way) and will "backflush" down the hot water line (which is disconnected below the sink) as this is the only place that it can go. At first, the water came out in a very fine mist. I sort of worked the cold water on and off a few times and wiggled the weed-whacker line around at the same time, and more black rubber pieces came out. I could now see that the black rubber pieces were the remnants of some sort of gasket or washer. Then, I noticed a small piece of red rubber sticking out of the end of the line. I took a needle-nosed pliers and pulled out a 2 inch piece of red rubber that looked like it was from an electrical connection! Once this piece of rubber came out, the water flow increased to full tilt! In the catch basin, there were several more small pieces of the red rubber and many, many of the black rubber crumbled pieces.



The black pieces were the remnants of the washer that had been in the hot water shut-off valve under the sink, so, just for good measure, I replaced it with a 1/4-turn valve (only takes a 1/4 turn to turn it on or off). I have no idea where the red rubber piece came from. I can only assume that it got into the water line somewhere "downstream" during construction or the installation of the hot water heater or something and worked its way up to the faucet.



I took the dime out, replaced the screen washer, replaced the handle to the flexible hose, reconnected all connections on the supply line, and turned on the hot water. It worked spectacularly! There was plenty of hot water pressure and everything was fine. The cost of repair was minimal with the only actual part purchased being the 1/4- turn valve for under the sink.

Check the cutoff valve under the sink to be sure it's fully on. If it is then the cartridge in the faucet may need to be cleaned or replaced.