Super low sink pressure when washer or toilets run

[Theant]

Background: house built in 1986, well water, pressure tank. I do all the plumbing, but we only bought the house a couple years ago, so problems may or may not be my fault

Water pressure in our sinks is normally really good. It's great in the showers.

But when the washing machine is filling, the pressure in the sinks drops way down. If someone flushes a toilet at the same time, the sink pressure is literally just a trickle of individual drops.

Of course the sinks have aerators, whereas the toilets & washer do not, which partially explains the pressure differential -- but still, I don't think the sink flows should drop so ridiculously low like this.

I've tried partially closing the valve that feeds the washer, and also tried an inline pressure regulator (the kind for RVs), but neither solved the problem. Both just make the washer fill really slowly -- the pressure in the sinks is still crap.

I even bumped up my well switch settings up from 40-60psi to ~50-75psi (cut in-cut out) -- no improvement. It seems any extra pressure is immediately stolen by the washer/toilets.

What else can I try?

Thanks,
Anthony

 

[Reach4]

When you detect "low pressure" at the kitchen sink, what does the pressure gauge at the pressure switch indicate? If the gauge says the pressure is fine there, then look for a restriction, such as a clogged cartridge filter.

If the pressure at the gauge stays lower than the cut-in pressure, the pump is not keeping up for some reason.

In PA I would expect a submersible pump (down the well), but tell us where the pump is.

If you don't have a helper to read the gauge as you turn water on and off, you could make a cellphone movie of the gauge, and maybe shout what is happening in the kitchen to be picked up by your cellphone microphone.

 

[Sponsor]

 

[Theant]

Thanks for your reply. Yes, the pump is in the well.

The pressure gauge drops from ~75 down to ~50, then the pump kicks on, as usual. The sink flow is roughly the same the whole time.

There's a tiny filter in the end of the kitchen sink supply line, and one in the head of the faucet. I cleaned those (and cleaned behind the aerator in the bathroom faucet), but they weren't very dirty/clogged, and it made no difference.

 

[Jadnashua]

Are any of the pipes galvanized steel? The ID of those over time can become barely the size of a soda straw before they eventually rust through and leak. That may be why they put filters, to block rust flakes from clogging up the valves.

People confuse pressure with volume. If the system pressure gauge is running normally, showing 50-70psi, you have a volume/restriction issue...not pressure. Now, you won't get any volume without pressure, but having pressure, if you have a restriction, depending on the size, you may not get any volume.

 

[Reach4]

I suspect a clogged whole house filter.

Since filling the toilet also reduces the sink hot water flow, expect the restriction to be before the tee that feeds cold water the water heater.

Could be your softener. Put that in bypass, and see if that makes a big improvement in flow.

But get a GHT pressure gauge. Cheap. Easy. Informative. Can connect to a laundry tap, drain for the water heater, or the outside hose bib. Typically a hose bib is not fed through a filter. So if that pressure stays up, but everything else drops, you know the restriction after the tee to the hose bib.

 

[Theant]

No galvanized pipes. It's all copper except what I've replaced with pex. And yes, both volume & pressure are low in the sinks when a toilet is flushed.

Softener is currently out of service. We do have 2 whole-house filters, and I just changed them, which only resulted in a small improvement.

Thinking about it though, I suppose simply having 2 filters is probably causing a significant pressure drop, right?

Our water has a high iron content and is also acidic. So we have a peroxide injector first, which oxidizes the iron, so that a filter can remove it. Next is a 10-micron Culligan fine sediment wound-string filter. After that, an acid neutralizer (big tank like a softener with media that I refill ~annually). Finally, a 5-micron Ronaqua block activated carbon coconut shell water filter, mainly to try to improve the taste of the water.

When I change the filters every 1-2 months, both are thoroughly brown from the iron.

 

[Reach4]

Our water has a high iron content and is also acidic. So we have a peroxide injector first, which oxidizes the iron, so that a filter can remove it. Next is a 10-micron Culligan fine sediment wound-string filter.

That is going to clog up fairly quickly, I would think, with iron oxide.

Finally, a 5-micron Ronaqua block activated carbon coconut shell water filter, mainly to try to improve the taste of the water.

Carbon block filters normally have a lot of pressure drop.

With many filter housings, you can remove the filter element. The water still passes through. So if the water flows much better without the cartridge, you have found your limiting factor. One way to get less pressure drop is to use a filter with a bigger cartridge. A 4.5 x 20 spun or pleated element will have a lot less drop than a pleated or spun 2.5x10 inch filter cartridge. With carbon block filters, the water passes long-ways through the element, rather than radially outside to in as it would do with a regular cartridge.

I am thinking that you might run your drinking water through the carbon block, but not your shower. But if you need to carbon-filter for all of your indoor water, get a backwashing carbon filter. Those will last a lot longer, and have much less pressure drop.

Since you don't have filter bypasses, it is important to have spare o-rings on hand, plus silicone grease to lightly lube the o-rings. A leaky o-ring, when you have no spare, means your water system is out of commission.

What is the water pressure at a laundry tap or the WH drain when you are experiencing reduced flow.

 

[Theant]

OK, I put a gauge at the laundry sink. Before flushing the toilet, the gauge showed 60 psi, and the gauge by the pressure tank also showed 60 psi.

Then I flushed a toilet, and while the toilet was running, the sink gauge showed 40 psi, while the pressure tank gauge showed 55 psi.

Next I tried bypassing both whole-house filters. I ran the kitchen sink, then flushed a toilet, and surprisingly the pressure/volume was only slightly improved.

But the acid neutralizer was still online. When I bypassed that (with both filters still bypassed), then finally the sink pressure/volume remains pretty good while the toilet is flushed.

So the acid neutralizer seems to be the biggest source of pressure drop.

My pressure tank has a label on it that says:

Model:
HT-20 HT20B

Max working pressure:
100 PSI 75 PSI

I don't see anywhere that it says which model mine actually is... but from what I'm reading, it sounds like it's not recommended to go above about 80psi anyway.

 

[Reach4]

I guess your mystery is solved.

I don't find those HT-20 or HT20B numbers for a neutralizer. What size is the tank-- 10x54, or 9x48, or what?

I am guessing this is not a backwashing neutralizer, so the calcite turned into a concrete-like solid in the tank. Backwashing can keep things fluffed up.

https://terrylove.com/forums/index.php?threads/well-water-considerations-while-backwashing-a-calcite-filter.85986/#post-617684

Search thru other threads that talk of calcite in https://terrylove.com/forums/index.php?forums/water-softener-forum-questions-and-answers.22/

 

[Theant]

The HT-20 / HT20B is my pressure tank.

The neutralizer is a Calcite Acid Neutralizer 7500-M from CleanWaterStore. It is backwashing and it's working properly. I just refilled the media a couple months ago.

 

[Reach4]

The neutralizer is a Calcite Acid Neutralizer 7500-M from CleanWaterStore. It is backwashing and it's working properly. I just refilled the media a couple months ago.

I would try to take steps to make sure the calcite is actually being backwashed sufficiently. If the gpm is too low, you don't get the bed expansion needed. If your calcite tank is unpainted (natural almond color), you can shine a bright light thru in a dark room during backwash. You can see the shadow of the media expand during backwash.

Trying to backwash thru a string filter may limit flow too much. What diameter is your calcite tank?