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magdiel1975
Low water Pressure after Toilet flush

Hi.. I am on a private well.. every time any of the 2 toilets are flushed, the water pressure drops both the cold and hot to almost a dribble. The pressure thank is OK, set at 28 psi as my pump calls for 30/50 psi. There is no air in the pipes as I have flushed the system several times arleady.

The pressure is great and showers run good, until the toilet is flushed. I had never noticed this before and this started about a week ago. Can't pin point what could be, please help, thank you.

Condoman
Re: Low water Pressure after Toilet flush

It sounds like the pressure tank may not be doing its job.

magdiel1975
Re: Low water Pressure after Toilet flush

I have checked the pressure tank and the pressure is good at 28psi, meaninig the bladder is good and is not losing air.

Lynne
Re: Low water Pressure after Toilet flush

You might want to try the Terry Love plumbing forum. http://www.terrylove.com/forums/index.php

magdiel1975
Re: Low water Pressure after Toilet flush

****UPDATE****
It ended up being the whole house water filter. DIdn't think it was that because I had just replaced it on the 1st of the month and today is the 17th... but once I removed it, it was filled with about a 16th of an inch layer of gunk and rust on filter... once I replaced it, I had no more issues of low pressure when flushing my toilets..I also did not think it was any blockage because I would ONLY get low pressure on the rest of the faucets when flushing the toilet, and thought if there was anything blocking I would get low pressure at all times..I have learned my lesson, thank God. I am amazed of how quickly that filter got so bad...thank you for the suggestion.

Mastercarpentry
Re: Low water Pressure after Toilet flush

If there's a service valve at the house, open all the faucets then open and close that service valve a few times, this may clear a blockage at that point. Still low flow? Using a garden hose faucet at the house, time how long it takes to fill a gallon bucket. Do the same thing with the same bucket at the well test faucet- both times should be within about 5 seconds of each other. If the well faucet is a lot faster and seems to flow normally this confirms the well and pump are OK and the problem is downstream toward or in the house. If both are slow something is happening before the line going to the house, either a blockage somewhere in the pump system or the pump is dying.

Check that the pressure switch on the well pump is operating when it should- it should come on within a few seconds of opening the test faucet fully. The contacts under the cover for it tend to get dirty and corroded in the humid atmosphere of a wellhouse. A small spritz of WD40 on the contacts then wiping with a piece of paper is the usual fix there, sanding with 220 paper if they are really bad first (shut the power off for this!).

Air pressure alone does not always indicate that a pressure tank is good. Based on how it's mounted it can hold air pressure for some time with a torn diaphragm before the trapped air mixes with water and the pressure drops. A piece of torn diaphragm or rust could be blocking it from inside allowing pressure in but not out, especially if it's mounted vertically with the water fitting at the bottom.

If all seems OK at the well to this point, do a flow test- you need to see 5 gallons per minute or more holding for 5 minutes minimum at the well faucet. Lack this and your well may be going dry causing the lack of pressure under heavy flow. Let's hope not!

This should be enough to point you to the source of the problem which should make the needed repair apparent. If you can find a copy, Max and Charlotte Alth's book "Wells and septic systems" is a great reference even if somewhat dated. Out of print now but can be found on the web cheap at the usual places.

Phil

dj1
Re: Low water Pressure after Toilet flush
magdiel1975 wrote:

****UPDATE****
It ended up being the whole house water filter. DIdn't think it was that because I had just replaced it on the 1st of the month and today is the 17th... but once I removed it, it was filled with about a 16th of an inch layer of gunk and rust on filter... once I replaced it, I had no more issues of low pressure when flushing my toilets..I also did not think it was any blockage because I would ONLY get low pressure on the rest of the faucets when flushing the toilet, and thought if there was anything blocking I would get low pressure at all times..I have learned my lesson, thank God. I am amazed of how quickly that filter got so bad...thank you for the suggestion.

Imagine you did not have a filter...

keith3267
Re: Low water Pressure after Toilet flush

Is this a new well or a new house?

Mastercarpentry
Re: Low water Pressure after Toilet flush

Looks like I posted while the update came in and I missed it! If your filter is clogging this rapidly, you may want to install a pre-filter to catch more of the gunk before it clogs the main filter. Sand filters do this job cheaply and can even be home-made from PVC pipe and fittings available anywhere.

Phil

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