Low water pressure when using hot water with multiple things in use

[Orangepeel]

Our home is older built in the 1950's. Water heater is new. When taking a shower and having the dishwasher or washing machine running the water pressure drops significantly. What can I do to minimize this? Is a blockage the cause of this? Or something else. I do have a pressure regulator on the line coming into the house and it is set at 60psi. Any help is appreciated. Thank you.

 

[Rand]

What pipe size do you have? If you have long runs of 1/2" pipe for example it can cause issues such as this.

All water "use" is based off your cold water pressure.. any water being used will lower it. hot or cold.

If you feel drastic drops in pressure it is usually plumbing related.. such that you should have bigger lines or higher pressure.
60psi isnt high. I have near 80psi city water.

Your issue needs investigation only answers you will get with the info provided will be guesses.

A tub running will lower water pressure everywhere in the house much more than a toilet or bathroom faucet. etc.

The way the water is distributed if several are T'ed off the same pipe it can also affect your issue.
Vs using a manifold.

For example my laundry room and downstairs bathroom are on the same 3/4" pipe so if I flush the toilet, run the shower (3gpm) start the washer and run the bathroom faucet they will have lower water pressure than my upstairs sink that is not directly attached to the same 3/4" pipe.
incoming water line from street is 1"

 

[f355spider]

With the water running in the house, I would adjust the pressure regulator up to 80psi and see if that helps. You need to adjust with water running to get a "dynamic" pressure reading, rather than static. But sometimes the pipes are simply undersized or going bad and a repipe is the only fix. I'm in a 1946 house and simply live with it.

 

[Rand]

I'm in a 1946 house and simply live with it.

I have a 1952 house but it was copper robbed while vacant, then replumbed fully with pex.. by redneck home remodelers..
its not quite the right way but its way better
than the copper pipes in the 1898 house I grew up in.
if you flushed a toilet or anything in that house you would get burnt in the shower etc.
Long undersize runs of pipe.

 

[eljefino]

You could restrict the water going into the dishwasher and/or washing machine. Close their inlet valves most of the way.

I'm on a well and have 20-40 psi and everything works fine.

I'd hesitate to crank up the street pressure on very old pipes. Suspect you have an internal restriction of some sort that developed over time, and continues to get worse. Agree with the idea of re-piping.

 

[Hall]

Water heater is new.

Since you mention this, you should realize that a water heater won't dramatically impact the water pressure. Did it change after installation ?

You could restrict the water going into the dishwasher and/or washing machine. Close their inlet valves most of the way.

That's not a good idea at all. It might work but it's a band-aid solution. Every device I've seen expects the supply valve to be fully open (personally, I open them 100%, then dial them back an 1/8th turn or so).

 

[mk378]

Water heater is new.

What type of water heater?
Continuous flow "instant" water heaters will restrict the flow during heavy usage in order to keep the temperature at the set point while the burner is firing at maximum btu. This does not happen with a tank type heater though of course those can run out of hot water.

 

[JohnnyG]

How high is the incoming, UNREGULATED pressure? The simplest solution is to remove the regulator entirely. They come with quite a bit of internal restrictions on their own.
Living in Pittsburgh PA years ago, unregulated pressure was 120 PSI. I never had an issue. Added a regulator and the problems began, including, but not limited to toilet valves being damaged due to the regulator also acting as a check valve (no internal bypass).
Added an expansion tank to address that situation, but ultimately I should never have installed the regulator and all would have been fine.

 

[mk378]

Most municipal supplies require an anti-backflow valve, which necessitates you have an expansion tank on your side of the valve to prevent pressure from increasing out of control as water is heated.

 

[TheLastWord]

Our home is older built in the 1950's. Water heater is new. When taking a shower and having the dishwasher or washing machine running the water pressure drops significantly. What can I do to minimize this? Is a blockage the cause of this? Or something else. I do have a pressure regulator on the line coming into the house and it is set at 60psi. Any help is appreciated. Thank you.

Where do live and when were faucets last replaced?

Many replacements have severe restrictions ala Jerry Brown, Gavin Newsom, and other "forward thinkers", etc.

60 psi is not an issue. Very common setting.

 

[Rand]

I'll say it again.
I know what I'd start by looking at but it needs investigation.

abit of what the OP is experiencing can be very normal esp. for a house without fully separate runs/manifold type setup.

We have no information that lets us progress beyond something between a guess and a wild guess at this point.

 

[4WD]

I look for these at the hardware store to find a smaller bore - goes on the washer hose at faucet … We wash often - not all in a day so speed does not matter …

 

[Orangepeel]

Electric hot water tank, I believe the lines are all 1/2 in copper pipe. Pressure without the regulator was around 120-130

 

[Nukeman7]

Our home is older built in the 1950's. Water heater is new. When taking a shower and having the dishwasher or washing machine running the water pressure drops significantly. What can I do to minimize this? Is a blockage the cause of this? Or something else. I do have a pressure regulator on the line coming into the house and it is set at 60psi. Any help is appreciated. Thank you.

Based upon the age of your house, I suspect that the issue is low flow, not low pressure. First, do you have low pressure/flow if you fully open up an outdoor cold water faucet (such as watering the lawn or washing a car) and take a shower while doing laundry with only cold water? If so, the issue is likely going to be corrosion in the incoming water line between the meter and your house. Homes built prior to the '80's commonly used 3/4" galvanized steel pipe for this supply line and transitioned to copper at the foundation. Rust and corrosion build up over decades and reduces the effective cross-section significantly to point of reduced volumetric flow. Think about using a 1/2" o.d. garden hose vs. a 3/4" o.d. hose to water your lawn...there is a notable reduction in volumetric flow.

The plumbers do a healthy business in my older neighborhood replacing these underground steel supply lines with PVC or PEX tubing. I replaced my water supply line 31 years ago with 1" hard copper tubing and have had excellent flow and pressure since.

 

[Orangepeel]

Based upon the age of your house, I suspect that the issue is low flow, not low pressure. First, do you have low pressure/flow if you fully open up an outdoor cold water faucet (such as watering the lawn or washing a car) and take a shower while doing laundry with only cold water? If so, the issue is likely going to be corrosion in the incoming water line between the meter and your house. Homes built prior to the '80's commonly used 3/4" galvanized steel pipe for this supply line and transitioned to copper at the foundation. Rust and corrosion build up over decades and reduces the effective cross-section significantly to point of reduced volumetric flow. Think about using a 1/2" o.d. garden hose vs. a 3/4" o.d. hose to water your lawn...there is a notable reduction in volumetric flow.

The plumbers do a healthy business in my older neighborhood replacing these underground steel supply lines with PVC or PEX tubing. I replaced my water supply line 31 years ago with 1" hard copper tubing and have had excellent flow and pressure since.

It seems to only be an issue when hot water is used. Cold water seems to have plenty of flow and pressure

 

[Nukeman7]

It seems to only be an issue when hot water is used. Cold water seems to have plenty of flow and pressure

How old is the hot water heater? Most of them have "heat saver" rubber inserts at the inlet and outlet pipe connections as a thermal break for maximum energy efficiency. It is possible that the insert could be partially clogged with sediment or collapsed, thus restricting flow. Have you drained sediment from the bottom of the water heater on a regular basis?

 

[burbguy82]

Water heater is new.

What kind of water heater do you have that is "new"

When taking a shower and having the dishwasher or washing machine running the water pressure drops significantly.

How long have you live there? Point of question is: do you have anything to compare it to? You mentioned a new water heater. Was this condition present before the heater was new?

 

[Orangepeel]

What kind of water heater do you have that is "new"

How long have you live there? Point of question is: do you have anything to compare it to? You mentioned a new water heater. Was this condition present before the heater was new?

Yes it was it's an a.o Smith water heater. Replaced the old one that was 12 years old about 60 days ago

 

[walterjay]

DO NOT take the pressure to 80 psi. I recommend 60. Seen too many problems at 80.

 

[burbguy82]

Yes it was it's an a.o Smith water heater. Replaced the old one that was 12 years old about 60 days ago

So the condition was present before you replaced the old heater with new........so the issue is not with the heater. It is a tank type correct?

If it is a tankless, there is your answer......it is the tankless.....

Hot side piping and hot sides of faucets and shower valves and such are more subject to corrosion, and mineral buildup over time. I am guessing you have galvanized piping somewhere? If not, it is a piping issue having more to do with size.