A.Y. McDonald DuraMAC Residential Booster Pump

Low inlet pressure is common in residential plumbing — water supplied from a storage tank, upper floors to serve, or an RO or filtration system taking its share of the available pressure. The DuraMAC Residential Booster installs inline and raises pressure where the supply falls short, starting automatically when water is drawn and stopping once demand ends.

Three modes of operation come from one dial. A pressure transducer monitors the system continuously; electronics are separated and sealed from the waterway for safety and field service. Durable stainless steel and no-lead brass connections, with dry-run protection.

Typical applications: whole-house supply lines, homes with RO or filtration installed, multi-bathroom and multi-story residences, tank-fed plumbing, and garden or utility lines.

Each DuraMAC Residential is a complete single unit, sized for the house it serves. When demand grows past 20 GPM, the next models up carry more water at the same boost: the Light Commercial to 35 GPM, the Dual-Mode Simplex to 70 GPM on one pump, and the Dual-Mode Duplex to 120 GPM on two pumps under lead/lag control.

Multi-pump staging is offered in the Dual-Mode family.

The figures below are the pressure this pump adds. That is what a pump curve measures — the impeller does not know what pressure is already on its inlet.

Models

Source: Baker Water Systems DuraMAC Booster Pumps catalog, rev 3/26, p. 237. PRV: A.Y. McDonald recommends a pressure reducing valve above this incoming pressure, so total boosted pressure stays below 80 psi. Many plumbing codes do not recommend system pressure above 80 psi; check local code.

Pressure added in PSI

Drawing from a tank or cistern — nothing arrives with pressure, so what the pump adds is what you get. Read the table straight through: the 70 PSI model delivers about 15 GPM at 42 psi.

Fed by a city main — this is a single-speed pump, so the boost arrives on top of whatever the main already delivers. A.Y. McDonald sizes it as arithmetic: 30 psi incoming plus the 35 PSI model gives 65 psi total. The catalog advises against exceeding 80 psi total boosted pressure, which is what the PRV column in the Models table is for.

Best operating range: 8 to 15 GPM. Below this range the pump recirculates internally, which causes vibration and premature seal wear. Above it, it cavitates and the motor draws past its rating. Most booster failures are pumps that were oversized for the building.

Zero flow is the shut-off point — a ceiling, not a working point. The table ends at the published maximum, 20 GPM. Figures are 60 Hz US data at full speed, digitized from the published curve in the Baker Water Systems DuraMAC Booster Pumps catalog, rev 3/26, p. 237, and rounded down. Best operating range is derived from the published curve; A.Y. McDonald publishes no efficiency curve for these models. Feet of head = PSI × 2.31.

Pressure Mode — starts on pressure drop, stops on low flow. Appropriate for the majority of light commercial and residential applications. The pump runs continuously while there is a need for water.

Flow Mode — starts on water flow, stops on low flow. For systems where pressure fluctuates or occasional leaks are present. The pump runs when water use exceeds approximately one gallon per minute.

Conservation Mode — starts on pressure drop, stops on low flow. For systems where incoming pressure is adequate for most uses and boosting is only needed at peak demand, such as multiple showers, bathtubs or irrigation zones running together. The pump runs only when system pressure is below the city supply pressure.

Parts in contact with the water, per the Baker Water Systems DuraMAC Booster Pumps catalog, rev 3/26.

Seals, impellers, controls and other service parts for this pump are listed on DuraMAC Booster Pump Parts — 20 GPM Residential, by part number.