Slow faucet needs more pressure.

July 23, 2009 5:13 AM

I need some plumbing help with regards to a slow faucet.

The landlord is dragging her feet on getting this fixed, so I thought I'd try to do it myself as long as it turns out to be a minor problem. Our kitchen sink has terrible water pressure - it takes about a full minute to fill a pint glass with water, which makes the sink difficult to use. I had just chalked it up to generally low pressure in the entire apartment until a plumber came out for a burst water heater and mentioned that the sink pressure was abnormally low.

The sink is just a standard stainless steel job, one basin, with a sprayer (also low pressure). The dishwasher and plumbing in the bathroom seem to be fine. Hot and cold are equally slow.

Where should I start looking? Any ideas what might be causing it?

posted by backseatpilot to home & garden (13 comments total)

Old house? THought so. IN the basement, the pipes are probably made of galvanized steel. These build up corrosion and deposits such that the flow is severely restricted. I once lived in a house where I would turn on the kitchen tap, take my morning shit and quickie shower, then go in and there'd be enough water to boil for oatmeal back in the kitchen. When we replaced the pipes, you literally could not blow air through some of them for all the corrosion.

Most likely, the landlord needs to replace the water piping...there's a lot of out-of-work plumbers right now, might be a good time to get one in for a side job.
posted by notsnot at 5:25 AM on July 23

(Apologies for not knowing the terminology)

I don't have a sprayer, but had this exact problem with my kitchen faucet. The problem turned out to be that there was a whole bunch of crud inside the faucet that was making it impossible for water to get out. I unscrewed the tip of the faucet, and took apart all the parts that were in the tip. One of the parts was a plastic filter, and it had a LOT of crud in there. At first, I thought it was just one piece (which I thought I had removed), but then the problem returned. I unscrewed the tip of the faucet again, and this time took all the pieces out of the tip of the faucet. Then I got into the plastic filter piece with a toothpick and an old toothbrush and removed all the crud: there was a whole lot I hadn't seen at first.

Now my kitchen faucet works great. YMMV
posted by 23skidoo at 5:28 AM on July 23 [1 favorite]

It would be worth it to check the screen in the faucet head- most have one. It may not completely solve your problem (I suspect notsnot is right), but it might help if you can replace or even clean the screen.
posted by Shohn at 5:30 AM on July 23

The metal screen thingy is actually called a aerator, many improvement stores sell this. But if it still takes a minute to fill a pint without the aerator, thats not the problem.
posted by glenno86 at 5:45 AM on July 23 [1 favorite]

Under the sink, there are shut-off valves for both hot and cold feeds to the faucet and sprayer. They turn clockwise to be fully open. Make sure they are both fully open.

Do check the screens in the faucet and sprayer. If your water heater burst, some particles from the lining may have broken free and gotten up to the kitchen faucet. Kitchen faucets are the only fixtures with mesh screens which might explain why the bathroom faucet is still running freely.

Unfortunately there is no roto-rooter for infeed water pipes. notsnot is right about corrosion build-up. You might need a new set of pipes although it seems unusual that only the kitchen sink is affected. Replacing pipes is not a simple task nor is it cheap.
posted by birdwatcher at 6:04 AM on July 23

If the aerator is clogged, that is a simple fix. You can get it off with a wrench, but protect the metal with a washcloth or other rag. Pull the parts out, clean out the gunk, and reassemble it. Put the plug in the drain or you will lose some parts.

If it is not the aerator, and both the hot and cold are affected, and there is no problem with the dishwasher, then the fixture may be to blame. The valve assembly may be bad. Does the dishwasher supply line attach under the sink? If so, the problem is downstream of the dishwasher line.

If the hot water is OK, and the cold is affected, then look at the cold water supply line uner the sink. Is it crimped, or bent sharply? If so, you can solve the problem by having that line replaced. For a first time plumber, you may find that task to be difficult and frustrating.
posted by Midnight Skulker at 6:41 AM on July 23

In addition to what notsnot, birdwatcher and midnight said above, there is also a device called a 'diverter' that diverts water between the faucet and the sprayer. These are frequently problematic when corrosion is in the line, they get crusty and don't open fully. It's worth it to take it out and have a look. (here is a howstuffworks.com walkthrough)
posted by kuujjuarapik at 7:08 AM on July 23

If it is a Moen faucet (the kind with a single lever that you turn this way or that for hot and cold), then it could have a clogged insert. This will be a brass tube-type thingy inside the middle of the faucet.

I have either cleaned out or replaced a few of these and it fixes it.

If you have separate handles for hot and cold, well, the aerator is your only hope.
posted by Danf at 7:11 AM on July 23

Thanks for the tips so far. To elaborate a little bit:

The faucet is the typical two-handled job. Both hot and cold are affected by low pressure. I don't have any direct evidence that the dishwasher is or is not affected, but the dishes come out clean.

Underneath the sink, plastic hoses connect to the faucet and sprayer. I'm not sure how far they travel, but I think they go all the way to the basement - there are similar (color coded!) blue and red plastic lines that hook up down by the water heater. I don't remember offhand where the dishwasher hooks up.

I'll check the screens, but this has been an ongoing problem since we moved in (well before the heater problem).
posted by backseatpilot at 7:24 AM on July 23

Here's an idea...

Under the sink, where the plastic hoses connect to the colored ones, disconnect them (after turning off the valves) and then see what the water flow is. You need to determine if the problem is in the faucet or the house plumbing, and this is the first step. Eliminate the faucet from the equation and see what the water SUPPLY is capable of delivering.

If it is trickling out of that hose, it's plumber time. If not, then you should concentrate on the faucet. They come apart rahter easily, with some puzzling. Take it apart as far as you can and clean inside it.

Worst case, investigate replacing it entirely, but cleaning usually helps.
posted by FauxScot at 7:52 AM on July 23

Underneath the sink, plastic hoses connect to the faucet and sprayer. I'm not sure how far they travel, but I think they go all the way to the basement - there are similar (color coded!) blue and red plastic lines that hook up down by the water heater. I don't remember offhand where the dishwasher hooks up.

The blue and red lines might be PEX, which would mean the place has already been replumbed. We had our old galvanized pipes (which have a life span of roughly 40 years) replaced two years ago with red and blue PEX.
posted by Big_B at 8:45 AM on July 23

Alos, if I am correct about the PEX installation, the lines usually come from a manifold of somesort located where the main comes into the building. These manifolds can sometimes be valved - i.e. you can shut off individual lines.

But to me if both the hot and cold have this problem at the sink then it is related to something in the faucet.
posted by Big_B at 8:47 AM on July 23

Well, I took the faucet apart and couldn't find an obvious blockage. I guess it's back to nagging the landlord. Thanks, all.
posted by backseatpilot at 5:51 AM on July 28