The MEV Water-Saving Valve

The MEV, or meter efficiency valve, is a patented American-made device installed on the user side of a building's incoming water line. It creates a steady back pressure through the water meter so that the meter sees a consistent, solid column of water rather than a flow broken up by pockets of air. Because almost no water meter can distinguish air from water, removing that inconsistency stops the meter registering air as consumed volume. BMI holds the exclusive right to distribute and install it in Toronto and the GTA.

Because it does not measure water. It measures movement. Single jet, multi jet and turbine positive displacement meters, which between them account for the overwhelming majority of meters in service, register the rotation of an internal element as flow passes through. Air moving through the meter turns that element in exactly the same way water does, and often faster, because it meets less resistance. The meter counts the rotation and bills it. It has no way of knowing what caused it.

It is normal and unavoidable. Air enters the distribution network at the municipal side through main breaks, repairs, hydrant use, pumping operations and pressure changes, and dissolved air comes out of solution whenever pressure drops across the system. In a tall building with booster pumps and constantly varying demand, pressure is changing all day. The air is not a fault in your building, which is why nobody notices it and why it goes on being billed.

Across the Toronto buildings where we have installed it, the recorded reduction in metered volume has run between fifteen and twenty-five percent, and those figures are listed on this page building by building. The variation depends on how much entrained air a given service carries, the meter type and size, and the building's consumption pattern. We review your consumption history before quoting, and if the indicators are not there we will tell you.

It is correcting the measurement, which is an important distinction to be clear about. Residents use exactly the same amount of water and notice no difference whatsoever in pressure, flow or service. What changes is that the building stops paying for volume it never received. It is a metering accuracy device rather than a conservation fixture, and it is worth presenting to owners in exactly those terms.

Yes. The valve is installed on the private side of the meter, on the building's own piping, and it does not touch, modify, bypass or interfere with the meter or with any municipal equipment. It does not slow or restrict the flow of water into the building. It conditions the flow so that the meter measures water accurately. It is standard plumbing work installed by a licensed contractor on the owner's side of the service.

No. The valve holds back pressure through the meter itself, which sits at the incoming service well upstream of the booster pumps and the pressure reducing stations that actually set what arrives at a suite. Flow and pressure at the fixture are unaffected. In the buildings listed on this page, no resident complaint has been attributed to the installation.

No. There is no filter, no cartridge, no strainer to clean and no scheduled maintenance interval. The internals are acetal and stainless steel inside a ductile iron body with a fusion epoxy coating, and the unit is designed to sit in the line and do nothing that requires attention. It is adjustable if circumstances change, and removable if the building ever wants it out.

It is manufactured in sizes from two and a half inches through to twelve inches, and the selection follows the size and configuration of your incoming service rather than the size of the building. We confirm the service size, the meter type and the available run on the user side during the site visit, before anything is ordered.

Yes. The valve is certified to NSF/ANSI 372 for lead content and to NSF/ANSI/CAN 61 for drinking water system components, and it also meets MIL-S-16293F Type 2. The body and access cover are ductile iron to ASTM A536 with an NSF-certified fusion epoxy finish inside and out, and the internals are acetal and 304 stainless steel.

Yes, briefly. The valve is fitted into the incoming main, so the building supply has to be closed while it goes in. The outage is a matter of hours rather than a day, it is scheduled with property management, residents are notified in writing in advance, and it is normally taken early in the day. Once the main is refilled and vented, service is back to normal.

It does provide a secondary benefit. The device is designed to protect downstream equipment from the pressure spikes that travel in on the incoming service, which are among the causes of premature failure in meters, valves, fixtures and appliances. That is not the reason most buildings install it, but it is a real characteristic of the product rather than a marketing claim.

On your own meter, against your own history. We record readings at commissioning and then compare metered volume over the following billing cycles against the same period in previous years, normalising for occupancy and for any unusual events such as a main flush or a filled pool. The comparison is made on the corporation's data, so the board is not asked to take a supplier's word for the result.

On the user side of the water meter, in the incoming service room or mechanical room, downstream of the meter and upstream of the building distribution. Horizontal is the preferred orientation, although the device will function in any orientation. It has to be installed where it cannot be submerged, and with enough clearance around it for later service, which we confirm before ordering.

Ten years on the valve itself, from the manufacturer, alongside our own workmanship warranty on the installation. Because BMI is the exclusive distributor for Toronto and the GTA, a warranty question is handled by the company that installed it rather than routed through a chain of suppliers.

No. If the corporation is not billed on metered volume, there is no over-registration to correct and the valve has nothing to act on. It is worth confirming, because some buildings are metered for part of their consumption and not for the rest, and some have separate services for irrigation or a commercial component that are metered independently. We will look at how your building is actually billed before quoting.

The measurement is the trial, and it runs after installation rather than before. What we can do beforehand is review your consumption history against the building's size, occupancy and comparable properties, which is a reasonable indicator of whether entrained air is likely to be a material factor. Speaking to the property managers at the buildings listed on this page is also something we encourage.