Connecting Multiple DAB Esybox Boosters

Engineering-Led Selection · Watermain Supply · Houston, TX

Connecting Multiple
DAB Esybox Boosters

Twin, triplex and quad constant-pressure systems from one platform — what adding a pump actually buys you, which family pairs how far, and how a group is piped and commissioned so it stages the way DAB designed it to.

4Pumps, One Group
0External Control Panels
+68 PSIThree Pumps vs One, Same Flow
1-888.510.4036Talk to a Person

The Short Version

  1. More pumps means more pressure at the flow you actually need. At 63 GPM a single 60/120 Max delivers 30 psi. Two deliver 87. Three deliver 98. Each pump carries a share of the water, so each one works higher on its own curve. The one figure that does not rise is the shut-off ceiling at zero flow.
  2. Every Esybox family pairs wirelessly. No panel, no PLC, no master controller. The pumps elect a leader, stage in sequence, rotate the lead and hold a reserve if you tell them to.
  3. How far each goes: Mini3 and Diver pair to two. Esybox and Esybox Max group to four.
  4. Esybox Max is the commercial answer. One pump, two on a twin dock, three on a triple, four by joining two twins — up to roughly 230 GPM on a published triplex table, without a manifold you fabricate.
  5. Buy one, add later — except the dock. Pumps are the same whether alone or grouped. The dock is sized for the count, so decide the base now even if the second pump comes next year.
  6. Against a fabricated skid it wins on five fronts — price, lead time, getting it through the door, servicing one pump without shutting the building, and seeing the whole system from a phone.
  7. Size the group on the calculator first. A pair that covers peak but runs both pumps at 30% of best efficiency all day is the wrong pair.
DAB Esybox Max multi-pump booster set installed in a mechanical room

Decision 1 · The Principle

Why Two Pumps Instead of One Bigger One?

Because a building’s demand is a shape, not a number, and one pump sized for the top of that shape spends most of its life in the wrong part of its curve.

A hotel draws 150 GPM at seven in the morning and 6 GPM at three. A single pump able to deliver 150 has a best-efficiency point somewhere near 100. At 6 GPM it is either short-cycling against its tank or, on a drive, running at a speed where the motor and seals are doing very little useful work. Every hour spent there is wear without water.

Two pumps of half the size change the shape of the problem. One pump carries everything below roughly 75 GPM and sits near its own best-efficiency point doing it. The second starts only when the first reaches full speed and pressure still falls. At three in the morning one pump idles or sleeps while the other is off. Both spend their lives closer to where they were designed to run.

Then there is the morning one of them fails. With a single pump, the building has no water until a truck arrives. With a pair, it has reduced capacity and nobody notices until someone reads the display.

And it lifts the pressure you can holdThis is the part most people miss. Splitting the flow between two pumps moves each one to a stronger point on its own curve, so the pair holds a higher pressure at the same delivery than one pump could. On a 60/120 Max at 63 GPM that is 30 psi from one pump against 87 from two.

The ceiling is the exception: shut-off pressure at zero flow is set by the pump model, so four Esybox units still top out where one does. If the top fixture needs more pressure than a single unit can add, the answer is a stronger model or credit for the pressure your main already supplies — both of which the calculator handles.
The three things a group buysFlow. Roughly the sum of the pumps at any given pressure, on a common manifold.

Turndown. One pump handles the small hours near its efficiency point. The others sleep.

Redundancy. One pump down is reduced capacity, not no water. With a reserve configured, it is no change at all.
Worked exampleA 60-unit apartment needs 132 GPM at a 79 psi setpoint. One Esybox Max 60/120 covers about 35 GPM at that duty on a tank — not close. Two on a twin dock reach the published twin table; three on a triple dock cover it with margin and leave one pump able to fail. The realistic everyday load is nearer 80 GPM, which two pumps carry while the third rests.

Decision 2 · Against the Alternative

Why Not a Conventional VFD Booster Skid?

The traditional package is pumps, drives, a control panel, transducers, a fabricated manifold and a hydropneumatic tank, engineered to order and welded onto a base. Esybox Max puts most of that inside the pump and turns the base into the manifold. Here is what that changes for the person paying for it.

What the job needs Conventional skid Esybox Max set
Variable speed drives Separate VFDs in a panel, field-wired to each motor One inside every pump. No panel, no motor leads to run.
Staging and lead rotation PLC or booster controller, programmed on site In the pumps. They elect a leader and stage themselves.
Pressure sensing Suction and discharge transducers, wired back to the panel Both sensors integral to each pump.
Manifold Fabricated steel, welded, with isolation and check valves The ESYDOCK base is the manifold. Check valve integral per pump.
Enclosure and controls space NEMA panel, wall or floor space, disconnect, control wiring None. Each pump is its own disconnect point.
Pressure tank Hydropneumatic tank, often 30 to 120 gal, floor space and precharge 2 L integral per pump; external vessel only where cycling demands it.
Remote visibility BMS integration, or nothing H2D app as standard; Esy I/O adds BMS and Modbus.

Price

Fewer bought components, no panel to build, no field wiring between panel and pumps, no structural base to fabricate, and no rigging charge for a one-piece skid. In our experience an Esybox Max set lands 30 to 50 percent below a comparable fabricated package at the same duty. Get both quotes and compare the installed number, not the equipment number.

Lead time

A fabricated booster is engineered to order: submittal, approval, build, ship. Twelve to sixteen weeks is normal and it starts after the submittal is approved. An Esybox Max set is pumps plus a dock, from stock. When a booster dies in an occupied hotel, that difference is the whole decision.

Getting it into the room

A skid arrives as one piece and needs a door, a path and often a crane. Esybox Max arrives as parts: 66 lb per pump unit, 20 to 60 lb for the dock. Two people carry it down a stair and assemble it in place. DAB calls this On Site Assembly, and on a retrofit in an existing building it is frequently the difference between a job that is possible and one that is not.

Servicing one pump

On a welded manifold, pulling a pump means breaking flanges and draining a section. On a dock, the pump unlocks and lifts off while the others keep running. The building stays in water. There is no crane and no shutdown notice under residents’ doors.

Footprint and noise

A twin dock is roughly 9 × 32 in and a triple 9 × 49 in, against several feet for a comparable skid — DAB puts the reduction at about 50 percent. The motors are water-cooled, so there is no cooling fan. DAB states the units are quiet enough for installation in inhabited rooms, which matters when the pump room shares a wall with a unit.

Redundancy without a bigger panel

N+1 is three settings on a keypad, not a control sequence someone has to write and commission. Configure a reserve and it sits idle, wakes itself for a minute every 23 hours so it never seizes, and takes over the moment a duty pump faults.

Who stands behind it

DAB Pumps S.p.A. was founded in Mestrino, Padova in 1975 — over fifty years in water technology, and the company that introduced the first fully integrated electronic booster with no external components. 24-month warranty from date of purchase under DAB’s published terms.

It grows

A skid sized for today is replaced when the building outgrows it. A dock takes another pump. Buy a twin dock, run one pump, add the second when the occupancy or the fixture count says so.

Where a fabricated skid is still the right answerAbove 76.6 GPM per pump or above 136 psi of boost, Esybox Max runs out and a conventional multistage package is the honest recommendation. The same applies where a specifying engineer has written a skid into the documents, or where the building needs a pressure zone above what any Esybox can add. We sell both — ask, and we will tell you which one your building is.

The Line

Four families, all self-contained, all wireless. They differ in flow, pressure, where they sit and how many join a group.

Esybox Mini3

22 GPM · 79 psi · pairs to 2

Single residence and light commercial. Two pair wirelessly; the ESYTWIN MINI dock stands them side by side. Self-priming to 26 ft.

View & Buy →

Esybox

32 GPM · 85 psi · groups to 4

Larger homes, small multifamily, light commercial. Up to four in one group; ESYTWIN docks a pair, ESYDOCK gives one unit four plumbing orientations.

View & Buy →

Esybox Max

76.6 GPM per pump · to 136 psi · groups to 4

Hotels, hospitals, mid-rise, process. Single, twin and triple docks; quad by joining two twins. Single or three phase.

View & Buy →

Esybox Diver

31.7 GPM · 80 psi · pairs to 2

Submersible for tanks, cisterns and wells. Two identical units run as a pair — alternating, or the second supporting the first.

View & Buy →

Decision 3 · Family

Which Family Should the Group Be?

Pick the family on pressure first, then flow, then where the water comes from. Pairing does not change the first two.

Family Max per pump Pressure ceiling Max in group Dock / pairing hardware Suction Power
Mini3 22 GPM 79.8 psi settable 2 ESYTWIN MINI 60218780, or free-standing wireless Self-priming to 26 ft 115 or 230V 1Ø
Esybox 32 GPM 85 psi settable 4 ESYTWIN 60162081 for a pair; ESYDOCK 60150514 single Self-priming to 26 ft 230V 1Ø
Esybox Max 76.6 GPM 83 / 97 / 136 psi differential by model 4 ESYDOCK MAX 60199045 · 2 ESYDOCK MAX 60199055 · 3 ESYDOCK MAX 60199056 · quad = two twins + kit Flooded or pressurised; 13 ft lift with foot valve 208-240V 1Ø or 380-480V 3Ø by model
Diver 31.7 GPM 80 psi 2 None — two units share the tank and discharge Submersible 230V 1Ø

Per-pump maxima are opposite ends of each curve and never occur together. The pressure ceiling shown is at zero flow; at any working flow a group holds more pressure than a single unit. Group capacity is read off the manufacturer’s twin and triplex tables, not by multiplying a single-pump maximum.

The pressure test comes firstIf the top fixture needs 90 psi at the pump and the building is on a tank, no number of Esybox units gets there — each one stops at 85. That job is an Esybox Max 60/120 or 85/120 from the start. Run the sizing calculator before you decide how many.
Mixed families do not pairA group is identical pumps. DAB requires the same hydraulic connections, the same maximum speed and the same firmware across every unit in a set. An Esybox does not join a Max group, and a 60/120 does not join an 85/120 group.
DAB Esybox boosters serving a multi-storey apartment building

Decision 4 · The Commercial Platform

Esybox Max — One Pump to Four on the Same Dock System

This is where the multi-pump idea pays for itself. The Max is built to be assembled on site as a set, not bought as a skid.

A conventional commercial booster arrives as a fabricated skid: pumps, drives, transducers, a control panel and a manifold, welded together in a factory to a duty you specified months earlier. It goes through the mechanical-room door in one piece or not at all, and if the building outgrows it, it is replaced.

Esybox Max separates the pump from the base. Each pump is a complete vertical multistage unit with its own drive, both pressure sensors, a check valve, a 2 L vessel and the display. The dock is the manifold. A pump is lowered onto its dock position and locked; the hydraulic connections engage on the way down. DAB calls this on-site assembly — the pieces go through a normal door and up a stair separately.

The pumps then find each other wirelessly and behave as one booster. There is no panel because there is nothing for a panel to do: staging, lead rotation, reserve logic and setpoint alignment all live in the pumps.

DAB Esybox Max twin booster set on a 2 ESYDOCK MAX base
Configuration Base Approx. footprint Published flow reach Typical use
Single ESYDOCK MAX · 60199045 One pump, four piping orientations To 76.6 GPM Small commercial, no redundancy required
Twin 2 ESYDOCK MAX · 60199055 9 × 32 × 15 in To ~153 GPM on the 60/120 and 85/120 tables Duty / assist, or duty / standby
Triplex 3 ESYDOCK MAX · 60199056 9 × 49 × 15 in To ~230 GPM on the 60/120 and 85/120 tables Duty / assist / assist, or duty / assist / standby
Quad Two 2 ESYDOCK MAX + connecting kit Two twin sets piped to common headers Double the twin curve, per DAB Large commercial, N+1 with real capacity behind it

Flow figures are the far end of DAB’s published group tables, where pressure is lowest. Working duty sits well inside them. Footprints from the 2026 accessory sheet.

Max model Phase P1 max Current Max head Max differential
45/120 M 208-240V 1Ø 1.97 kW / 2.68 HP 9.4 A 190 ft 83 psi
60/120 M 208-240V 1Ø 2.68 kW / 3.6 HP 12.5–11.5 A 226 ft 97 psi
60/120 T 380-480V 3Ø 2.65 kW / 3.5 HP 4.4 A 226 ft 97 psi
85/120 T 380-480V 3Ø 3.50 kW / 4.7 HP 5.3 A 315 ft 136 psi

Current draw is per pump. A triplex of 60/120 M on single phase is three 12.5 A circuits, not one. The 45/120 T listed in DAB literature is not currently stocked.

Quad is two twins, piped togetherThere is no four-position dock. A four-pump set is two twin docks connected so all four pumps see the same suction header and the same discharge header. DAB publishes five acceptable header arrangements: face-to-face through a central connection block, or looped headers extending from one twin to the other in either direction, or flow-through with inlet one side and outlet the other. The drawings are schematic. Header size, isolation, supports and bypass are engineered for the flow, not copied off the sheet.
Four piping orientations on every dockSingle, twin and triple docks all accept building piping four ways: both connections left, both right, in-right-out-left, in-left-out-right. Unused ports are plugged. That is what lets the same set fit a room whether the main comes in on the near wall or the far one.
DAB Esybox Max multi-pump booster set for hotels and hospitals

Decision 5 · Capacity

Group Performance — What You Actually Get

DAB publishes separate one, two and three-pump tables for Esybox Max. Put them side by side and something useful falls out: the pressure rows are identical in all three. Only the flow scale changes.

Read across 1 2 3 4 5 6 7 8 9 10 11 12 13
Pressure added — 45/120, ft 190 190 190 190 171 148 126 116 106 85 75 23 —
Pressure added — 60/120, ft 226 226 226 226 226 200 174 164 153 133 122 69 13
Pressure added — 85/120, ft 315 315 315 315 315 276 246 233 213 186 169 95 30
Flow — 1 pump, GPM 0.1 10.6 15.9 21.1 26.4 31.7 37 39.6 42.3 47.6 50.2 63.4 76.6
Flow — 2 pumps, GPM 0.1 21.1 31.7 42.3 52.8 63.4 74 79.3 84.5 95.1 100.4 126.8 153.2
Flow — 3 pumps, GPM 0.2 31.7 47.6 63.4 79.3 95.1 111 118.9 126.8 142.7 150.6 190.2 229.8
Flow — 4 pumps, GPM 0.2 42.2 63.4 84.6 105.6 126.8 148 158.6 169.0 190.2 200.8 253.6 306.4

From DAB Esybox Max US Technical Sheet 50250413, 01/2026, pages 7, 9 and 11. The 4-pump row is the published 2-pump row doubled, per DAB’s note on the twin curve sheet: “for the four-pump version it is necessary to double the flow rate.” Zero-flow entries are shut-off, a ceiling rather than a working point. The 45/120 has no published point at its last column.

Read it down a column, and then acrossDown a column is the pressure gain. Find 63.4 GPM: the 1-pump row puts it at 69 ft, the 2-pump row at 200 ft, the 3-pump row at 226 ft. Same water delivered, 30 psi against 87 against 98. Each pump is carrying a third of the flow, so each sits near the flat top of its own curve instead of the far right of it.

Across a row is the flow gain. Column 8 on the 60/120 is 164 ft of pressure added — 71 psi — at 39.6 GPM with one pump, 79.3 with two, 118.9 with three, 158.6 with four.

Both readings come off the same published table. Adding pumps buys more water, more pressure, or any mix of the two — up to the shut-off figure in the first column, which is fixed by the model.
Worked selectionA 12-storey condominium needs 115 GPM at 71 psi of added pressure, which is 164 ft. Read down the 60/120 row to 164 ft — column 8. One pump gives 39.6 GPM there. Two give 79.3, still short. Three give 118.9, which covers it. A triplex 60/120 is the set; add a fourth if the building must also survive a pump being down at peak.
Electrical scales with the countEach pump keeps its own supply. A 60/120 M triplex is three single-phase circuits at 12.5 A, not one 37 A circuit. Three-phase 60/120 T is three circuits at 4.4 A. The 85/120 T is 5.3 A per pump. Size the service to the sum, size each circuit to one pump.
Esybox and Mini3 are different hereDAB publishes no combined performance table for grouped Esybox, Esybox Mini3 or Diver — only the single-pump curve. For those families, group capacity is selected against the system curve rather than read off a published table, and a twin is never advertised as simply double. That published group data is one of the reasons Esybox Max is the commercial answer: the numbers exist.
Set Dock Dock size Dock weight Connections Pump unit
1 Esybox Max ESYDOCK MAX · 60199045 9 × 15 × 15 in 19.8 lb 1-1/4 in to 2 in 66.1 lb each
2 Esybox Max 2 ESYDOCK MAX · 60199055 9 × 32 × 15 in 39.7 lb 2 in 66.1 lb each
3 Esybox Max 3 ESYDOCK MAX · 60199056 9 × 49 × 15 in 59.5 lb 2 in 66.1 lb each
4 Esybox Max Two 2 ESYDOCK MAX + connecting kit Two twin docks, piped to common headers 79.4 lb 2 in 66.1 lb each

Nothing in a four-pump set weighs more than 66 lb. That is the On Site Assembly argument in one line.

Decision 5b · Controls and Visibility

Esy I/O and the H2D App

The group runs itself. These two are how the building talks to it, and how you find out about a problem before a resident does.

Esy I/O — part 60206085

An electronic expansion module that gives the group wired inputs and outputs. It carries four digital inputs, an analogue input and a Modbus RTU RS485 serial port. That is how a float switch in a break tank, a low-suction pressure switch, or a remote alarm contact reaches the pumps — and how the pumps reach a building management system.

One module serves the whole group. DAB lists it as available on single, twin, triplex and quad configurations alike. If the building has a BMS and the owner expects the booster to appear on it, this is the part that gets missed on the first quote and found during commissioning.

When you need itA break tank with level control. A low-suction cutout tied to the city main. A remote alarm to a front desk or an answering service. Any BMS or Modbus requirement in the specification. Without it, the group is self-contained but silent to the rest of the building.

H2D — the app

H2D is DAB’s platform on mobile and desktop, pairing with the Wi-Fi built into every Esybox Max. It replaces DConnect on current-generation products. From a phone or a browser you set and see system pressure, read alarms, and check instantaneous and historical consumption.

Local configuration through the app needs no internet connection and no subscription. Remote access — watching a building you are not standing in — requires an active H2D plan and an internet connection at the site.

For a property manager with several buildings this is the difference between hearing about a pressure problem from a tenant and seeing it on a phone. For a service contractor it means arriving with the fault already known and the right part on the truck, rather than diagnosing on site and coming back.

DAB Esy I/O expansion module, part 60206085, for BMS and Modbus interfacing
DSync — commissioning a set onceConfigure the first pump with your phone. DSync detects the language, time and units of the country of installation, then pushes the configuration to the remaining pumps in the set automatically. On a triplex that is one set-up instead of three, and it removes the commonest commissioning error — three pumps configured slightly differently.
What owners get out of itRemote monitoring turns emergency callouts into scheduled service. A pressure drift, a rising start count or a repeating dry-run alarm shows up as data before it shows up as a complaint. That is the argument for the subscription, and it is worth making to the owner rather than the contractor.
Older stock, older platformLiterature across the Esybox line spans the DConnect and H2D generations. Current-generation product connects to H2D directly; older date codes may need a DConnect Box or a firmware update first. Confirm against the unit you are actually buying.

Decision 6 · Count and Role

How Many Pumps, and What Does Each One Do?

Count comes from flow. Role comes from three settings DAB exposes on every group.

The group detects how many pumps it has — DAB calls this N. You then tell it two things: how many may take part in pumping (NA) and how many may run at the same time (NC). On any individual pump you can set a reserve preference (IC), which puts it last in the starting order.

Those three settings are the whole vocabulary. Every configuration a contractor would ask for is a combination of them.

You want Pumps NA NC Reserve Behaviour
Duty / assist 2 2 2 none One runs; the second starts when the first hits full speed and pressure still falls. Lead rotates on hours.
Duty / standby 2 1 1 one One runs alone. The reserve starts only if the duty pump faults. Capacity is one pump.
Preferred duty, full capacity 2 2 2 one The non-reserve starts first; the reserve still joins at high demand. Preserves one pump without giving up twin flow.
Duty / assist / assist 3 3 3 none Stages one, two, three as demand climbs. Full triplex capacity, no spare.
Duty / assist / standby 3 2 2 one Two share the load. The third is a true spare that starts only on a fault. N+1.
Electrical cap 4 4 2 none All four rotate through duty, but no more than two ever run together. Limits inrush and service size.
The pumps balance themselvesStarting order is not fixed to a physical position. A pump that has run continuously for the ET time — factory two hours, settable one minute to nine hours — drops to lowest priority so another takes the lead. Set ET to zero and the lead changes on every restart.
Reserves do not seizeA pump that has sat idle for 23 hours is given top priority long enough to move water for one minute, then returns to reserve. It applies to every pump, and it is why a standby unit that has never been needed still starts when it finally is.
N+1 costs a pumpDuty / assist / standby on three pumps gives you two pumps of capacity, not three. If the building needs three pumps’ worth at peak and you also want a spare, the answer is four. Decide which you are buying — capacity or resilience — before the dock is ordered, because the dock does not grow.

Decision 7 · Hydraulics

Piping Rules That Decide Whether the Group Behaves

The control logic assumes symmetry. Break it and the pumps fight each other instead of sharing.

One common discharge manifold

Every pump discharges into the same header. Two pumps on two separate lines to the building are two boosters, not a group, and the wireless link will not fix that.

Symmetric suction

Each pump must see the same inlet condition. A pump at the end of a long suction run starves before its neighbours, stages late, and can dry-run trip while the others are fine.

Identical pumps, identical firmware

Same model, same hydraulic connections, same maximum speed, same firmware version. DAB states all three. A mismatched unit either will not associate or will regulate against the others.

Isolation valves and unions on every pump

DAB’s piping sheets show them for a reason: a pump comes off its dock for service only if it can be isolated. Add a bypass around the set so the building stays on city pressure while the group is down.

No second check valve close to the pump

Each unit has one built in. A field check valve immediately downstream traps pressure between the two and confuses the sensors. On the Diver, DAB specifies no external check within 3 ft of the discharge.

Suction-side losses are shared losses

An undersized suction line, a clogged strainer or a partly closed valve on the common inlet reduces what every pump can deliver at once. The group cannot stage its way out of a starved header.

The integrated vessel is not a tank

Esybox and Max carry 2 L each; the Mini3 and Diver less. DAB says plainly the vessel is not a water reserve. If overnight leakage or a long dead-band causes cycling, add an external vessel on the discharge header and precharge it to setpoint less restart differential less about 3 psi.

Thermal expansion still needs somewhere to go

A booster closes the system. Where there are storage water heaters, a thermal expansion tank at the heater is required regardless of how many pumps are on the dock.

The published tables assume the manifold DAB suppliesEsybox Max group tables are measured on the ESYDOCK base. Pipe a set onto a field-fabricated header and the friction in that header comes off the delivered flow. For families where DAB publishes no group table at all — Esybox, Mini3, Diver — never size a pair by multiplying the single curve.

Decision 8 · Start-up

Commissioning a Group

Wireless association is a two-minute keypad step. The settings that follow are what make it a booster rather than a collection of pumps.

1. Finish the hydraulics and electrical first. Every pump on its own supply, every pump primed. Association before water is a common cause of false dry-run faults on day one.

2. Associate the pumps. On each unit, enter the AS function and hold the association key for five seconds; the pumps within range find each other and join one private wireless network. The display shows the connected units and their signal strength. A group holds a maximum of four.

3. Answer the propagation question once. If the pumps carry different sensitive settings — setpoint, restart differential, timing, control gains — the group asks which pump’s configuration to copy to the others. Answer from the pump you set up first. From then on, changing a sensitive setting on any pump aligns it across the group automatically.

4. Set the roles. NA, NC and any reserve preference, from the table above. These are group settings; set them once.

5. Set ET. Two hours is the factory value and is right for most buildings. Shorten it where you want faster rotation; set it to zero if you want the lead to change every restart.

6. Precharge the external vessel, if one is fitted, with the system drained: setpoint minus restart differential minus about 3 psi.

Settings that stay per-pumpDisplay contrast and brightness, manual-mode speed, address if manually assigned, and the reserve flag. Everything that affects pressure regulation is shared; everything cosmetic is local.
Replacing a pump laterA factory-fresh unit dropped into an existing group adopts the group’s sensitive settings automatically, provided its firmware matches. Match the firmware first; then it is a lift-on, associate, done.
The DSync shortcut on MaxConfigure one Max fully, then DSync pushes its software and settings to the other new units in the set. On a triplex that is three set-ups reduced to one.

Questions Buyers Ask

If the answer you need is not here, call. Multi-pump selection is exactly the conversation we want to have.

Can I buy one now and add the second later?

Yes, on every family. The pump is the same unit whether alone or grouped. What you choose now is the dock — a twin dock with one pump on it is a normal single installation until the second arrives.

Do two pumps give me more pressure?

Yes, at any flow you are actually drawing — each pump carries half the water and works higher on its curve, so the pair holds a higher pressure than one could at the same delivery. What does not double is the shut-off ceiling at zero flow, which is fixed by the model. Two Esybox units still top out at 85 psi with nothing running.

Do I need a control panel?

No. Staging, lead rotation, reserve logic and setpoint alignment live in the pumps and travel over the wireless link. The Esy I/O accessory adds BMS and Modbus if the building needs to see the group.

Can I mix an Esybox with an Esybox Max?

No. A group is identical pumps with identical firmware. Even within the Max range, a 60/120 does not group with an 85/120.

How is a quad Max built if there is no four-pump dock?

Two twin docks, piped to common suction and discharge headers using one of DAB’s five published arrangements, with all four pumps associated into one group. Header sizing is engineered, not copied.

What happens when one pump fails?

The group skips it. With a reserve configured, the reserve starts and capacity is unchanged. Without one, the building runs on the remaining pumps at reduced capacity until the failed unit is lifted off and replaced.

Does the group need an external pressure tank?

Often not for daily operation, since one pump modulates or sleeps at low demand. Where overnight leakage causes cycling, add a vessel on the discharge header and precharge it to setpoint less restart differential less about 3 psi.

Can two Divers run together in a well?

Yes — DAB supports two identical Divers, alternating or with the second supporting the first at high demand. DAB does not publish a twin performance table for the Diver, so size a pair from selection data rather than doubling the curve.

Which Max model do I need?

Pressure decides it. 45/120 adds up to 83 psi, 60/120 up to 97, 85/120 up to 136. Then flow decides the count. Run the calculator with your building and it checks the models against the duty.

What size wire and breaker for a triplex?

Each pump is its own circuit. A 60/120 M triplex is three single-phase circuits at up to 12.5 A each; a 60/120 T triplex is three three-phase circuits at 4.4 A. Size to the pump nameplate and local code, not to the group total.

How does the price compare with a fabricated booster skid?

In our experience an Esybox Max set lands 30 to 50 percent below a comparable package at the same duty, before you count the rigging and the field wiring a skid needs. Ask us for both quotes and compare the installed cost.

Do I need the Esy I/O module?

Only if the group has to talk to something else — a BMS, Modbus, a break-tank float, a low-suction switch or a remote alarm. Part 60206085, one per group, and it fits every configuration from single to quad.

Does the app cost money?

Configuring the pump locally with the H2D app is free and needs no internet. Watching the system remotely needs an active H2D plan and internet at the site.

Size the Group Before You Pick the Dock

The calculator returns the flow and pressure your building actually needs, then checks it against every DAB model we carry. Or send the building details and we will come back with a configuration and the reasoning behind it.

Run the Sizing Calculator Call 1-888.510.4036 Email the Building Details
Genuine DAB equipment, factory-new in original packaging — sold and supported by Watermain Supply, an independent industrial distributor. Engineering-led selection, based in Houston and serving the Gulf Coast. 1-888.510.4036
DAB, Esybox, Esybox Mini3, Esybox Max, Esybox Diver, ESYDOCK, ESYTWIN, DConnect, DSync and H2D are trademarks of DAB Pumps S.p.A. and are used here to identify genuine DAB products. Technical data on this page is subject to change by the manufacturer — confirm against the current installation manual before specifying.
Watermain Supply is a DBA of E4 Industrial LLC, an independent industrial supplier based in Houston, Texas.