Do municipal water meters measure entrained air?

  • Thread starter Thread starter gary.walker2
  • Start date Start date
  • Tags Tags
    Air Measure Water
Click For Summary

Discussion Overview

The discussion centers around the claim made by a device that purportedly saves residential water bills by preventing water meters from measuring entrained air bubbles in the supply line. Participants explore the physical plausibility of this claim, its implications for water measurement, and alternative methods for reducing water usage.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant questions the physical sense of the device, asking whether entrained air bubbles could significantly affect the measured volume of water.
  • Another participant argues that there is not much entrained air in a domestic water system, suggesting that the device's claims are unlikely to be valid.
  • A different viewpoint mentions that while entrained air can affect readings in specific contexts, such as testing engines, the proposed device would not be effective for domestic water supply.
  • Concerns are raised about the device potentially slowing down water flow, leading to a false impression of reduced water usage while actually decreasing the amount of water used.
  • One participant notes that air vacuum assemblies are used in waterlines to manage air, indicating that air presence is acknowledged in plumbing systems, but questions the effectiveness of the proposed meter modification for average homeowners.

Areas of Agreement / Disagreement

Participants generally disagree on the effectiveness of the device, with multiple competing views regarding the presence and impact of entrained air in domestic water systems. The discussion remains unresolved regarding the validity of the device's claims.

Contextual Notes

Participants express varying assumptions about the amount of entrained air in domestic water systems and the effectiveness of alternative water-saving methods. There is no consensus on the technical feasibility of the proposed device.

gary.walker2
Messages
1
Reaction score
0
I have just now seen an advertisement on tv that claims to save up to 40% on residential water bills by inducing the meter to not measure the volume of air bubbles represented by entrained air in the supply line. This device is to be placed immediately DOWNSTREAM of the meter and presumably somehow compresses the bubbles upstream of the meter! Not being an engineer but with average knowledge of homeowner issues and a desire to keep my water bill down, I'm curious. Does this device make physical sense. Could entrained air bubbles really significantly affect the measured volume? To whoever wants to respond I'll be grateful and will answer questions about the claims although I think I've stated it succinctly. gw
 
Engineering news on Phys.org
No, that isn't possible. I don't know if it can do what it says to entrained air (unlikely), but there isn't that much entrained air in a domestic water system to begin with.
 
At the kinds of flow rates I'm interested in when testing engines, entrained air can make a significant (perhaps a few percent) difference to the true reading. The idea that I can fit something downstream of this (rather than spend thousands of pounds on a fancy water meter) is ridiculous, and would make bugger all difference for a domestic supply anyway.

File under C for Cobblers.
 
upstream, maybe downstream, no way
I can't imagine there is actually that much air

I would be concerned that all it was doing is slowing down the flow, making it appear like your getting the same amount of water for less $$$, but in actuality slightly reducing the water you use.

If you are serious about saving water and money there are better ways. improved showerheads, always wash full loads of clothes, hand wash dishes, toilet water reductions, etc
we even re-use the water that I get from the de-humidifyer heating the house for laundry water (we get ~5 gallons per day)

don't skimp oin the showers, though, you can lose friends

dr
 
russ_watters said:
No, that isn't possible. I don't know if it can do what it says to entrained air (unlikely), but there isn't that much entrained air in a domestic water system to begin with.

First of all, there is a lot of air in domestic waterlines, hence "air vacuum assemblies" are installed in high points of waterlines. But for the average homeowner, this meter air strainer would probably only be the most beneficial if you live on a hill or higher than the watermain you're connected to.
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 39 ·
2
Replies
39
Views
15K
  • · Replies 2 ·
Replies
2
Views
4K
Replies
4
Views
6K
  • · Replies 2 ·
Replies
2
Views
5K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 2 ·
Replies
2
Views
20K