How Many HP Pump for a Condo Water Tank (Philippines Sizing Guide)

Most condo water tank pumps fall into four bands. A single unit with a 200 to 500 liter tank needs about 0.5 HP to feed a shower, lavatory, and kitchen sink. A low-rise building (roughly 2 to 4 storeys) runs on 1 to 2 HP for its transfer or booster duty. A mid-rise condo of 8 to 15 storeys typically needs 3 to 7.5 HP, usually delivered through a duplex set rather than a single pump. A high-rise building with pressure zoning needs 10 or more HP per zone, since each zone is effectively its own booster system.

Where a project lands inside a band depends on the number of floors, units per floor, the elevation between the tank and the highest fixture, and how many fixtures run at the same time during peak hours. These ranges are a starting point for budgeting and specification, not a substitute for a flow and head calculation on the actual building. JOHOB Hardware Trading sizes the pump, panel, and tank together once we have the building's basic parameters, so the HP figure quoted matches real demand instead of a rounded-up guess that adds cost without adding reliability.

Pump HP comes down to three inputs: flow (Q), head (H), and efficiency. The working formula is:

kW = (Q x H) / (367 x efficiency)

Q is flow in cubic meters per hour, H is total head in meters, and efficiency is typically assumed between 0.40 and 0.75 depending on pump condition and type. Flow is the peak simultaneous demand the system has to meet, not the average draw across the day, since a pump sized for average use will fail during the morning and evening peak. Head is the vertical lift from the water source to the highest fixture, plus friction loss through the pipe run and fittings, which is why a taller riser or a longer horizontal run pushes HP up even if unit count stays the same. Efficiency accounts for mechanical and hydraulic losses inside the pump itself; using a lower efficiency figure in the calculation is the safer assumption for older or budget-grade equipment, since it avoids undersizing. Once kW is calculated, converting to HP is a straight multiplication (1 HP equals 0.746 kW). Getting an accurate HP number means having accurate Q and H figures for the specific building, not applying a rule of thumb across every project.

As an illustrative calculation only, not a specific project: a mid-rise condo with a peak simultaneous flow demand of 15 cubic meters per hour and a total head of 45 meters (rooftop tank elevation plus friction loss through the riser) works out to kW = (15 x 45) / (367 x 0.60), which equals roughly 3.07 kW, or about 4.1 HP after converting at 0.746 kW per HP. That figure lands inside the 3 to 7.5 HP band expected for an 8 to 15 storey building, and in practice this demand would be split across a duplex pump set with a VFD panel rather than run on a single pump, so each unit carries roughly half the load and the standby unit takes over automatically if the lead pump trips. The same formula applies whether the building is 8 storeys or 15, the difference is simply the Q and H values fed into it. Buildings with higher fixture counts per floor, longer riser runs, or elevated static head from tank placement will land toward the top of the range even at the same storey count, which is why two 10-storey condos can specify different HP for the same booster duty.

Rounding up HP as a safety margin feels conservative, but it carries real ongoing cost. An oversized pump draws more electricity than the system needs for every hour it runs, since motor draw scales with rated HP, not actual load. It also cycles on and off more often, because it satisfies demand faster and shuts down sooner, and that cycling wears out check valves, mechanical seals, and motor bearings faster than a right-sized pump running a steadier duty cycle. Oversizing also forces a larger VFD duplex control panel than the load requires, since the panel has to be rated to the pump, not to the building's actual demand, adding upfront cost with no performance benefit. The correct fix for uncertainty in a sizing calculation is a wider efficiency margin in the Q and H inputs, not a jump to the next HP size. Right-sizing based on the building's actual flow and head numbers keeps both the capital cost of the pump and panel, and the running electricity cost over the life of the system, in line with what the building actually demands. A correctly charged hydropneumatic pressure tank absorbs small draws so the pump does not short cycle on a single hand wash.

JOHOB Hardware Trading supplies booster, transfer, and submersible pumps for condo systems, along with VFD duplex control panels built around Inovance and Chutian drives for buildings that need staged or zoned pressure control. We also supply hydropneumatic pressure tanks, flexible hoses, and valves so the pump room is delivered as a complete package. Water storage, including FRP, GRP, HDG, and stainless steel modular tanks, is supplied through our sister brand TankSmith, which handles the turnkey tank installation. Equipment across our supply is sourced from an ISO 9001 certified partner factory, with CE marking on electrical components and TUV SUD testing where applicable, and tanks carry WRAS-certified panels. We supply nationwide across NCR, Luzon, Visayas, and Mindanao, including PEZA and SBMA economic zones. For a condo project, the pump, panel, and tank are quoted and coordinated as one package rather than as separate purchases, which keeps the flow, head, and control logic consistent across the whole system instead of mismatched components sourced from different suppliers.

To get a specific HP recommendation instead of a range, send us:

• The number of units and floors
• The tank type and capacity (existing or planned)
• The elevation between the tank and the highest fixture
• If this is a replacement, the nameplate data from the existing pump

A riser diagram helps if one is available, but is not required to get a preliminary recommendation. We respond to RFQs within 1 business day. Pricing is quote-based since it depends on the final flow, head, and panel configuration, standard lead time is 21 to 35 days for ex-stock equipment or 45 to 90 days for made-to-order configurations such as custom VFD panels, and 12% VAT applies for VAT-registered buyers, with zero-VAT available for PEZA and SBMA locators and registered exporters.

Reviewed: August 2026