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Plumbing - single-knob shower has cold, but no hot water. Causes?

Home is 10 years old, was vacant for a year before I bought it. One shower has cold water only, no hot. The single knob turns on the water, with decent pressure. As you rotate the knob to get more hot water (mixing in hot with the cold), it does not warm up. When you dial it all the way to hot, there is no water flow at all. It appears that the hot water is not able to get through 'somewhere'. How to diagnose? 1) other showers and adjacent sinks all have warm/hot. 2) second floor bathroom, no easy wall access 3) no apparent leaks currently Could the hot water to JUST that one fixture have been turned off? Where? (If there was a leak, and this was the former owners way of dealing with it.) The hardware store guy said it might be the 'stem', and showed me a couple of $15 parts that could be bad. Is this the kind of repair that a semi-handy person could complete? (I have completed a variety of different home repairs, but would not call myself an expert!)

Public Comments

  1. It is very unlikely that this location would have cutoff valves for hot and cold. Most likely the valve has broken or become clogged. You will have to shut off the water, cover the drain to keep from losing parts and take the top of the handle and pull out the guts. Most single handle controls are accessible from inside the shower without going into the wall. If you can read a brand, you can go to the website and look at pictures and diagrams to see how it comes apart. If possible, go to a faucet or plumbing supply place with your parts rather than a hardware store or home improvement store - more focused knowledge.
  2. investigate the mixing & blending device...i had the same problem
  3. Well......There could be a hot shut off valve (only) for that shower only. Check that first. Noi telling what previous homeowners have done. Other most likely culpret is the "stem." But this may just be clogged. It's easy to remove and replace so try cleaning and replacing before buying a new one. All faucets are a little different but basically you just remove a center screw and the stem will come out. TURN OFF THE WATER TO THE SHOWER BEFORE you do this or you will take an unexpected shower!