Hot water tap flow

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Bob Buchanan

Well-known member
Joined
Mar 3, 2005
Posts
3,038
Location
Philadelphia, PA
For the past several months the hot water flow from my kitchen and bathroom sinks has lessened to the point it is now just dribbling from each tap. The cold flows normally from all taps. Also, the shower hot water runs normal. I looked at the lines coming from the water heater and followed them until they disappear behind the kitchen cabinetry. I checked the filters in both spigots and they are not the problem. The bathroom, kitchen, and water heater are on one side of the coach and the shower is on the other. Typical Class C arrangement.

Would the pressure head have anything to do with this? As the shower works OK, I wouldn't think so.

My only other thought would be debree in those two lines -- or ????

How does one check those lines that go behind cabinets? If I took it to a repair place, what would they do to blow those lines out?

TIA
 
Bob,

Since the shower, which is on the opposite side of the coach, is working normal I would suspect your line leading to the descrepant faucets is clogging up somewhere after the lines separate.  Probably a buildup of minerals from the water. The problem is likely not too far from the water heater.

You might tru flushing the descrepant lines out with limeaway or such.
 
Ron said:
Bob,

Since the shower, which is on the opposite side of the coach, is working normal I would suspect your line leading to the descrepant faucets is clogging up somewhere after the lines separate.  Probably a buildup of minerals from the water. The problem is likely not too far from the water heater.

You might tru flushing the descrepant lines out with limeaway or such.

I'm in agreement Ron... In my house I had a simular problem.. I found both the hot and cold pipes were clogged with miniral build up where they crossed over the furnance (why they plumbed it that way I don't know... I had one (supply) side replaced professionally and on the hot side I took the old pipes to the hardware store (these are pipes, not hoses) and had them custom cut new ones, 1.5 times as big around as the original pipes (3/4 instead of 1/2) Wife came home, turned on the hot water to wash dishes like she always did, got the good initial flow she was used to and instead of trickeling off to nothing as the anti shock chambers depressurized,,, it kept on flowing (And continues to do so to this date)  However this took 40 to 50 years to build up to the point of clog.


Another posibility is a line has gotten kinked or pinched, I'd have to know where the lines go and well... he's going to have to inspect the entire line, not just the easy part, cause Murphy says it is NEVER the easy part
 
Bob,

If your problem is mineral deposits (probably), introduce about a gallon of plain vinegar into the HWH and get it hot. Then remove the filters/strainers from the offending HW faucets and run until you get some of the vinegar solution coming out, then shut the faucets and let stand for 30 minutes or more. Afterwards, turn on the faucets and flush thoroughly to get rid of all the crud. You'll also have to drain and flush the HWH - possibly several times. It'll be a messy task, but should get the job done. Also, I'd recommend you stay away from products like LimeAway. They contain phosphoric acid which, while great for grout, plays hell with brass and copper fittings. 
 
Bob Buchanan said:
For the past several months the hot water flow from my kitchen and bathroom sinks has lessened to the point it is now just dribbling from each tap.

Bob,

All of my faucets in my motor home have a screen just below the faucet assembly. About once a year the hot water faucet in the bathroom and faucet in the shower in the bathroom slow noticeably. I simply turn OFF the the water supply, remove the faucet handle and then remove the the faucet assembly. If I look into the hole where the assembly was, I can see a very fine screen which is pressed into the bottom of the hole. I take an ice pick and gently pry the screen out of the hole (the screen is shaped with a upward bevel along the sides--kind of like a flat-bottomed U with much shorter sides). Use the ice pick on the sides and not the screening surface. After removing the screen, I use a towel to cover the hole and very briefly hit the pump switch. The brief water flow flushes out any sediment which falls away from the screen back into the pipe. I clean and replace the screen and faucet assembly and am good for another year. The screen can be pressed back into place with your finger.

This has always solved my problem. I don't know whether your faucets are of the same design but it doesn't take much time to disassemble a hot water faucet and look for a fine screen pressed into the bottom of the hole. Be careful not to tighten the faucet assembly to tight. Mine are plastic and it doesn't take much to break something. O-rings make the seal and over-tighting is not necessary. I you don't find the screen as describe above, inspect the faucet assembly to see whether it is plugged with white sediment from the hot water tank.

I hope this help.

Regards,

Richard
 
I have the same experience as Richard - mineral build-up on the screens in the water spigots of the galley and bath sinks.  It's a common problem in many areas.  Simply unscrew the head of the outlet and clean of the mesh strainer. Some vinegar may help, but usually it simply rinses out.

You may need pliers to unscrew the fitting. If so, place a cloth in the jaws to avoid scratching the finish.
 
Thank you everyone for all the great suggestions. In fact, it's again I am reminded of how valuable this forum is to me and has been since I found years ago. Now I must decide the best approach from those posted. I believe I will begin with the least intrusive, and work up to the messier ones. Unfortunately, I am not hooked up to water at present so will have to wait until I can have a fresh water input hose to refill with. However, I will be trying Richards suggestion (that Gary uses as well) as it doesn't require emptying the HWH. I see that my fitting are plastic as well, so not sure just how to turn them as they seem to be in there pretty tight. Would hate to break one. If that does or does not work, I do plan to empty the tank and clean it out per several suggestions when I have a fresh water supply.

Thanks again -- and I will post my results as soon as I get this fixed.
 
Richard:

[Mine are plastic and it doesn't take much to break something. O-rings make the seal and over-tighting is not necessary.]

Couldn't get those plastics fittings loose - and I could see that if I pressed harder,they would surely break. That was true on both the bathroom and kitchen faucets. So . . . I unhooked the hot water hose from under the sink and went in the back door. I took a narrow screw driver and scrapped the sediment off the bottom of the filter. Not as affective because I couldn't get the bottom of the filters cleaned as well as I would have liked -- HOWEVER, I now have hot water that flows almost a well as the cold tap on both sinks.

In addition to the suggestions here, there was one I was going to try that I found via Google prior to receiving your suggestion. It suggested draining and cleaning the HWH, then with the water still turned off, placing the end of a garden hose into the spigot (w/the hot water knob turned on). I have one of those plastic tube fittings with an on/off valve that would allow me to stick the end well into the spigot. Then, after wrapping a towel around the end, turn on the hose valve. This would back flush the line and force the sediment from the filter back into the HWH tank. From there, another cleaning could be done on the HWH if needed.

Not sure how much a filter is even needed on the hot water side of a spigot. I have a filter on the outlet that would catch the heavy stuff - and I rarely make tea with hot tap water.  :D  In fact, if I wasn't able to scrape enough sediment from the filter from the bottom side, I was going to just puncture it as a temporary fix.
 
Bob Buchanan said:
Couldn't get those plastics fittings loose - and I could see that if I pressed harder,they would surely break.

Bob,

I am surprised that you couldn't get the stem assemblies out of the faucets. One thing I failed to mention in my original post. Before removing the faucet handles, be sure to "turn the faucet ON." This should make loosening the stem assemblies easier. I use a closed end wrench to remove the stem assembly. This minimizes the possibility of stripping the plastic hex stem head. Sounds like your method has help with the flow. One thing I found was that when the faucet is shut OFF, a lot of sediment falls off of the screen and back into the tubing, especially on sink faucets. On the shower faucet the sediment can't fall back because the faucet base is horizontal. In fact, that is how I discovered so much sediment was being stopped by the screen and decided to flush the tubing by briefly turning the pump ON.

The cleaning method you found on Google sounds like it would help. However, I have found that many of the screen holes are tightly plugged with sediment and often take brushing with a tooth brush to get them clean. I am not sure that just back flushing would remove all the the blockage.

In any case, I am glad that you now have a good hot water flow. :)

Regards,

Richard
 
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