Two new Wilo products now available through Merion Pump: the Stratos MAXO-Z and the MVI.

Wilo continues to expand its commercial and industrial product line, and two additions are now available through Merion Pump Company. The Stratos MAXO-Z brings intelligent domestic hot water recirculation to the Wilo circulator lineup. The MVI is a high-pressure vertical multistage centrifugal pump covering applications from light commercial pressure boosting through heavy industrial process water. They serve different applications, but both fill genuine gaps in what the Wilo line through Merion can cover.

Wilo Stratos MAXO-Z: domestic hot water recirculation with hygiene intelligence

The Z suffix on the Stratos MAXO-Z tells you what is different from the standard Stratos MAXO. This is a wet rotor circulator designed specifically for domestic hot water circulation systems, with design decisions driven by the hygiene requirements of potable water applications rather than purely by the energy efficiency requirements of hydronic heating circuits.

The standout feature is the T-const. control function, which maintains a constant water temperature in the domestic hot water recirculation loop. In a conventional recirculation system, the pump runs on a schedule or at a fixed speed, and the water temperature in the loop varies depending on how much hot water is being drawn and how much heat the distribution piping is losing. T-const. adjusts the pump’s operating point continuously to maintain the target loop temperature, which reduces energy consumption during periods of low demand while ensuring that hot water is available immediately at every fixture when demand increases.

The thermal disinfection detection function monitors the loop for conditions that indicate a Legionella risk and flags when thermal disinfection may be required. In healthcare facilities, hotels, and multifamily residential buildings where domestic hot water hygiene is a regulatory requirement or a liability concern, this capability is genuinely useful rather than a marketing feature.

The pump housing is stainless steel, which is appropriate for potable water contact. Connection sizes cover 1.25, 2, and 3-inch flanges. Maximum operating pressure is 145 PSI. The fluid temperature range covers 32 degrees Fahrenheit to 176 degrees Fahrenheit for drinking water applications and 14 degrees Fahrenheit to 230 degrees Fahrenheit for heating water.

Connectivity follows the same pattern as the broader Stratos MAXO family. Bluetooth interface for commissioning and diagnostics via the Wilo app. Modbus RTU and BACnet MS/TP available via plug-in CIF modules for building automation integration. The Wilo Net interface allows multiple pumps to communicate directly for multi-pump coordination in larger domestic hot water systems.

The Stratos MAXO-Z is the right answer for any commercial building with a domestic hot water recirculation system where temperature maintenance, energy efficiency, and hygiene compliance are all design requirements. Hotels, hospitals, multifamily residential, university dormitories, and healthcare facilities are the natural applications. For buildings where the domestic hot water system is served by a commercial boiler plant, the GP Energy Products team handles the boiler side of that conversation. Visit gpenergyproducts.com for more on GP Energy’s commercial boiler capabilities.

Wilo MVI: high-pressure vertical multistage for demanding applications

The MVI is a different product category entirely. Where the Stratos MAXO-Z is an intelligent circulator for a specific HVAC and plumbing application, the MVI is a high-pressure workhorse for applications that need to move fluid at pressures that standard commercial HVAC pumps cannot reach.

The MVI is a non-self-priming, high-pressure, vertical multistage centrifugal pump with inline connections. Multistage means the fluid passes through multiple impeller stages in series, with each stage adding pressure. The number of stages determines the maximum pressure the pump can achieve, and the MVI series covers configurations from a few stages through higher-stage configurations that produce maximum operating pressures of up to 435 PSI depending on the model.

The product covers a horsepower range from one-third to 100 HP with peak efficiency flows of up to 750 GPM and head capacity of up to 980 feet. That combination of high pressure and significant flow range means the MVI addresses applications that sit between the standard commercial HVAC pump and the large industrial process pump, a range that is often underserved by catalogs that stop at one end or the other.

Construction is 304 stainless steel standard with 316 stainless steel available for applications requiring higher corrosion resistance. Seal options are EPDM or Viton depending on the fluid chemistry. ANSI class flanges and NEMA motor mounts ensure compatibility with standard building and industrial infrastructure. NSF 61 and NSF 372 certification covers domestic water applications.

The cartridge mechanical seal design allows seal replacement without removing the motor. The spacer coupling allows seal replacement without disconnecting the motor from the pump. For facilities where pump downtime is expensive and maintenance access is limited, those design decisions reduce the service labor and the system downtime required for a seal replacement.

Variable frequency drive is available on request for applications where variable flow control is required. In high-rise pressure boosting applications where the MVI serves pressure zones, a VFD-equipped MVI provides the same variable speed energy savings that a standard commercial circulator provides in a hydronic heating system, but at the pressures that high-rise applications require.

Applications for the MVI through Merion include pressure boosting for commercial and high-rise buildings, industrial circulation systems, process water, cooling water circulation, and irrigation. For high-rise domestic water applications where the MVI is part of a pressure booster package, the domestic water article we wrote on high-rise pump selection covers the pressure zoning and design considerations in detail. Visit merionpump.com for that reference.

For applications where the MVI is part of a packaged pump skid serving an industrial or campus distribution system, the FabPro Systems team designs and fabricates custom pump skids that integrate the MVI into a factory-assembled and tested package. Visit fabprosystems.com for more on FabPro’s packaged pump system capabilities.

What is available through Merion now

Both the Stratos MAXO-Z and the MVI are available through Merion Pump Company. For the Stratos MAXO-Z, Merion carries four models covering 1.25-inch through 3-inch flange connections. For the MVI, the full range from one-third HP through 100 HP is available with 304 stainless steel construction and EPDM or Viton seal options as standard.

Reach out to the Merion Pump team for product selection, technical support, and pricing on either product. If you have an application that fits either the domestic hot water recirculation profile of the Stratos MAXO-Z or the high-pressure multistage profile of the MVI, we will help confirm the right model for the specific operating conditions before anything is ordered.

References
1. Wilo USA. Stratos MAXO-Z product page including specifications, control functions, and application guidance. wilo.com/us/en_us/Products/en_us/products/stratos-maxo-z_id5173
2. Wilo USA. MVI product page including specifications, capacity range, and application guidance. wilo.com/us/en_us/Products/en_us/products/mvi_id5521
3.NSF International. NSF 61 and NSF 372 certification standards for drinking water system components. nsf.org
4. Hydraulic Institute. Pump Selection Guide for Multistage Pump Applications. pumps.org