Plumbing ? Slow hot water, banging pipes

Straightup

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My house is 47 years old and I am experiencing slow hot water at the kitchen sink only. I am running a portable dishwasher so the hot gets left on overnight (being hooked up to the dishwasher). Also when the dishwasher is not hooked up and the hot is turned on at the sink you can hear banging / clunking in the pipes below. All of the rest of the hots in the rest of the house seem to have normal flow.

We have no water softener, our water is pretty hard.

The water heater is about 12 feet from where it goes up to the kitchen sink and that line is copper (about 5/8 O.D. line). Then at the base of the cabinet there is a steel line with a compression fitting that goes up to the fawcett - about 18". I took that line out last night and didn't see any blockage / sediment in that line.

The fawcett is a pretty cheap $50 one and is about 10 years old. Maybe full of crud?

Thanks in advance for any suggestions. - Straightup
 

MTboatguy

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Re: Plumbing ? Slow hot water, banging pipes

Sounds like a cruded up faucet, the banging is coming from contact somewhere along the pipe, I had the same problem and found that my hot water pipe was secured with metal u brackets that allowed the pipe to move a bit when it heated up and expanded with the hot flowing through it, I took the u brackets off, then installed plastic isolation brackets, no more banging.
 

rbh

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Re: Plumbing ? Slow hot water, banging pipes

I am not a plumber, but I did see a program were they stated that all pipes should be attached to the studs/joist with clips so as to secure the pipes when the preasure is released through the taps.
I think they used soft/flexable lines at the tank and the sink, and hard lines for the distrabution.
Think of a garden hose when you turn it on with nothing on the end all that preasure makes it go snakey.

As for flow, check all the shut off taps are fully open, and use CLR on all the screens to eat away all the build up of gunk.
 

solar7647

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Re: Plumbing ? Slow hot water, banging pipes

Remove the tip of the faucet and see if the screen is blocked up. I have the same issue ever so ofter and just taking a pair of pliers and removing the tip of the faucet and cleaning the screen solves the issue.
 

scipper77

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Re: Plumbing ? Slow hot water, banging pipes

Get a bucket. Remove the line between the hot water shut off and the faucet. Now open the shut off valve directly into the bucket for a few seconds. Is there good flow there? If there is it.s the faucet.

They use flow restrictors to limit the throughput of the faucet. It doesn't take much to partially block a faucet.

If the flow is weak at the shut off then you "might" need to run a new line from the hot water tank to the kitchen. I'd likely call in a plumber at this point.
 

BuzzStPoint

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Re: Plumbing ? Slow hot water, banging pipes

Could be air in the lines.

My Faucet used to bang away, I too have a cheap faucet and was told after a bit of time, air is trapped in the faucet.


Also, Follow your pipes, Make sure they are tight and secured with proper clips. I've seen it too many times with wires and nails.

You can put on some Mini restors.
mini_resters.jpg
 

Beefer

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Re: Plumbing ? Slow hot water, banging pipes

Since the low flow is only on the hot, it is not your faucet as a whole, but may be the valve on the faucet. If the faucet is a one-handle type, it could be the cartridge. It's not Farah Fawcett, either (sorry, had to :p).

The banging is most likely what's referred to as a 'water hammer'. Common issue, (relatively) easy fix.
 

dvandsm64

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Jun 3, 2010
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142
Re: Plumbing ? Slow hot water, banging pipes

Since the low flow is only on the hot, it is not your faucet as a whole, but may be the valve on the faucet. If the faucet is a one-handle type, it could be the cartridge. It's not Farah Fawcett, either (sorry, had to :p).

The banging is most likely what's referred to as a 'water hammer'. Common issue, (relatively) easy fix.

i think he is exactly rite. it is called water hammer caused by trapped air. u need to bleed the air out.
 

Straightup

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Re: Plumbing ? Slow hot water, banging pipes

I want to quickly thank everyone for your responses. It is a 2 handle faucet, and I will check the valve. Working 15 hour days 'til the weekend, so will check it out then.

Thanks again.
 

dwco5051

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Sep 14, 2008
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Re: Plumbing ? Slow hot water, banging pipes

Since it is a two handle faucet and only the hot is slow that eliminates the aerator as the problem. I would remove the stem and check for a swollen washer or crud and/or a bad cup if it is a washerless faucet. Being that you said that it is a cheap faucet I would lean towards it being a compression shutoff and it may have a swollen washer which is cutting down the flow. The hot side is more prone to having this problem as the heat distorts cheap rubber faucet washers. If there is a shutoff on the hot supply line it could also be the source of your problem from the same causes.
 

scipper77

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Re: Plumbing ? Slow hot water, banging pipes

Another thing to try is to switch the hot and cold lines at the shutoff so that hot is cold at the faucet. If you now have good hot flow and poor cold you again have confirmed the faucet as the issue.
 
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