Plumbing question: Increasing garden hose flow rate

911_Dude · 01-27-2013, 08:01 AM

I have a lot of cars and bikes, which means a lot of vehicle washing going on. But I am not satisfied with the water flow rate coming out of the hose. I think the issue is restriction, not pressure. The house has good pressure (city water). Im pretty sure the water hookup to the detached garage is connected with the small (3/8"?) compression fittings, and I think that is my restriction. Problem is, they are three feet underground.

My question is: Can I get a precharged water tank like this

WaterWorker-HT-20B-Blue-20-Gallon-Vertical-Pressure-Water-Well-Tank
and connect it inline in my garage? Seems like it would work great for holding pressure for 4-5 gallons worth while I rinse the cars off. I just wanted to make sure I wasnt over looking some basic fluid dynamic law of pressure.

1990C4S · 01-27-2013, 08:14 AM

What is your water pressure?

John Rogers · 08:18 AM

One of the easiest ways to reduce fluid flow is to insert an orifice which is what that 3/8 diameter connector is acting like. So no matter what size hose you have flow will always be low. I would suggest increasing the size of the connection but if not possible due to local codes or laws then a water tank is your only option. Where I live the water line sizes are smaller now that in 1960 when our house was built so they will be more environmentally friendly........ If you put in a tank use a good filter/demineralizer system in the supply so the water will not leave spots.

look 171 · 01-27-2013, 09:10 AM

Take that compression out and see if pressure or volume increases. Get a pressure washer and set it on low so no damage to the vehicles.

911_Dude · 01-27-2013, 01:06 PM

Quote:

Originally Posted by john rogers

...then a water tank is your only option. ..... If you put in a tank use a good filter/demineralizer system in the supply so the water will not leave spots.

Thanks, and good call on the filter system.

Quote:

Originally Posted by look 171

Take that compression out and see if pressure or volume increases.

As mentioned, I cant get to the restrictive fittings. They are buried.

Quote:

Originally Posted by 1990C4S

What is your water pressure?

Not sure, but it seems like plenty

wdfifteen · wdfifteen's Garage

Quote:

Originally Posted by 911_Dude

Im pretty sure the water hookup to the detached garage is connected with the small (3/8"?) compression fittings, and I think that is my restriction. Problem is, they are three feet underground.

That is so wrong in so many ways. Who would do a thing like that?

Grog · 01-27-2013, 01:22 PM

A small booster pump with a discharge pressure switch might do the job. Maybe tap into a water line under/in the house/garage.

911_Dude · 02:17 PM

It may not be 3/8" but I remember thinking it was no 1/2" pipe flow. I was having the garage built and that detail was one of a million things going on at the time with the contractor and it hasnt really bothered me until recently. The flow is fine with the sink that is in the garage. But it just doesnt measure up with the hose. I think one of those accumulators should do the trick along with replacing the hose's screw type shut off valve with a ball valve. I think all I need is 4-5 gallons at a time to rinse off a car, and it will probably recharge very quickly. But I have a soap/foam sprayer that needs more pressure. When I use it I get a burst of about 10 feet, then it drops down to about 6-7 feet. That tells me there is enough system pressure, just not enough flow to maintain it. Yes? No?

GWN7 · 01-27-2013, 02:50 PM

It all depends on volume, not preassure. Most citys water supplys are about 65 PSI (it can varry from 50 PSI to 75 PSI depending on where you are accessing it) and the volume of water you get out of the city supply depends on the size of your water line.

What is the volume of your power washer? You will have to look up what it's GPM (Gallons per minute) flow rate is. With power washers they run between 1.5 GPM to 3 GPM on average. So if your power washer is 3000 PSI and uses 3GPM your addition of a 20 gallon storage tank would give you about 7 minutes usage of your power washer at full volume (not factoring in the refill rate of water supply to the garage).

If you do put the storage tank in your garage you should install a water supply back check valve so nothing can go back into they water supply system. While they are not required for a home they are for a business (up here that is).

sailchef · sailchef's Garage

Here's an idea. I thought about doing this for an outside solar hot water shower during the summer months.

Install a cistern on a second floor deck, framework,attic, etc.

a 50 gallon poly drum would be perfect. fill with existing water hook ups, hose etc.

Connect a 2 inch hose for car wash, open spigot, stand back. let gravity take over.

Kind of like a mini water tower.

GWN7 · 01-27-2013, 05:05 PM

Only problem is you would open the spigot and the hose would fill with water and that's about all. You might get a few seconds of water out. Once the initial "head" of the water preassure passed all you would get is a trickle of water out (what was being resupplied from the city). City supply to a house is 1/2" line (a few are 3/4"). You can't get out more than you put in.

look 171 · 01-27-2013, 06:49 PM

Quote:

Originally Posted by 911_Dude

Thanks, and good call on the filter system.

As mentioned, I cant get to the restrictive fittings. They are buried.

Not sure, but it seems like plenty

I am under the impression that the fitting is at the very end above ground. Sorry.

there should not be a reducer under ground. Unless its a code thing at your location, it is very strange for them to do that.

look 171 · 01-27-2013, 06:56 PM

How long is the run to the garage? Is there a regulator in front or in the basement (I do not know too much about plumbing in the colder climates)? The longer the run, the more pressure drop. We sometimes run a 1" pipe under the house but it bypass the regulator to get full pressure / volume to the back yard for washing purposes. You might want to check the pressure at the exterior faucet. it should read 60-65lbs. Then check the garage and see if there's any drop in pressure. If the pressure coming in is good, how about installing an additional line to the back of the house so you can wash the cars and make sure you bypass the regulator that feeds the house.

911_Dude · 01-28-2013, 03:32 AM

There is about a 75' run to the garage. Im pretty sure it was 1/2" PEX that was used. I also pretty sure there is no regulator between the house and the garage. I dont use a pressure washer, just a nozzle and a foam gun attachment.
Wouldnt the pressure tank solve this? Its actually a pressurized bladder tank, not just a reservoir.

A930Rocket · 01-28-2013, 04:03 AM

Every house we built had a pressure reducing valve. You might need to connect the garage line to the main before the PRV.

wdfifteen · wdfifteen's Garage

Quote:

Originally Posted by 911_Dude

There is about a 75' run to the garage. Im pretty sure it was 1/2" PEX that was used. I also pretty sure there is no regulator between the house and the garage. I dont use a pressure washer, just a nozzle and a foam gun attachment.
Wouldnt the pressure tank solve this? Its actually a pressurized bladder tank, not just a reservoir.

Yes, that would work for as long as the water in the tank held out. With a volume of water going in at 65 psi and a somewhat greater volume going out, you would eventually get back to the same volume problem you have now, but giving the tank a few minutes to recharge would bring you back up to full volume and pressure. It may not be a bad solution.

jpk · 01-28-2013, 06:30 AM

Check your flow rate by timing how long it takes to fill a 5 gallon bucket. I can't imagine you'd get less the 2.5/3 gallons per minute. I'd suggest a smaller electric pressure washer (like one of these: Amazon.com: 1.5 GPM - Pressure Washers / Outdoor Power Tools: Patio, Lawn & Garden)
and you should be golden.

sailchef · sailchef's Garage

Quote:

Originally Posted by GWN7

Only problem is you would open the spigot and the hose would fill with water and that's about all.

I was thinking of having it fill from the top with a auto shut off valve and an air gap between the top surface of the water and the fill tube to prevent back flow, or even a check valve. Flooding the house is not an option

look 171 · 01-28-2013, 09:51 AM

Quote:

Originally Posted by 911_Dude

There is about a 75' run to the garage. Im pretty sure it was 1/2" PEX that was used. I also pretty sure there is no regulator between the house and the garage. I dont use a pressure washer, just a nozzle and a foam gun attachment.
Wouldnt the pressure tank solve this? Its actually a pressurized bladder tank, not just a reservoir.

I know nothing about pressure tanks. The regulator is usually install right before the water enters the home.

GWN7 · 01-28-2013, 10:02 AM

Quote:

Originally Posted by sailchef

I was thinking of having it fill from the top with a auto shut off valve and an air gap between the top surface of the water and the fill tube to prevent back flow, or even a check valve. Flooding the house is not an option

Toilet tanks have a auto shut off valve.

Still the problem of volume. Your trying to fill a 2" hose with a 1/2" one.

A 45 gal drum contains about 6.6 cubic feet of water. A 2" hose (50' long) contains 4.25 cubic feet so you will use 2/3 of the water to just fill the hose. That leaves you 15 gals of water in the tank to work with. If your useage is larger than your supply (city water) you will run out.