Automatic water pump HITACHI WM-PV400XX2 (400 watts)

Automatic Water Pump HITACHI WM-PV400XX2 (400 W) 

     For pumping water from shallow wells (depth not exceeding 8 meters) or from above-ground water tanks. Easy to use with an automatic system operating in sync with the turning on and off of faucets. Compact size, space-saving installation. Delivers constant, stable pressure, eliminating the issue of interrupted water flow while using a water heater. Suitable for residences using water at multiple points simultaneously.

What are the key advantages of a square tank pump or constant pressure pump?

      Constant Pressure Water Pump Hitachi Eliminate inconsistent water pressure issues with a compact yet high-efficiency water pump. Designed for pumping water from shallow wells (up to 8 meters deep) or above-ground water tanks. Easy to use with an automatic system that activates according to the turning on and off of faucets. Compact size saves installation space. Provides consistent and stable pressure, preventing water interruptions while using a water heater.

- High power in a compact size, saving installation space
- Bladder Tank: The tank contains a rubber diaphragm filled with nitrogen gas requiring no gas refills throughout its lifespan, providing consistent and stable water pressure
- Durable and rust-free: Free from rust throughout its lifespan, rust-proof body, durable and strong
- Pressure Stabilized Unit: Regulates water flow rate and generates continuous pressure
- Brass Impeller: Newly designed pump in a Pyramid Shape delivers more water volume than before
- Safe: Equipped with a “Water Temp Relay” temperature sensor at the pump head and a “Thermal Relay” in the coil that cuts off operation when overheating, preventing other spare parts from heat damage
- Special Material: Pump cover made of special “PPV0” flame-retardant material to prevent the spread of fire
- Ventilation Fan Set: Helps dissipate heat from the unit, extending motor lifespan
- Easy to install for operation 
- Energy Label No. 5: Energy-saving label, highly cost-effective.
- Made of high-quality aluminum, heat-resistant, flame-retardant
- The water pump should only be used with clean water for domestic consumption

Suitable for: Large residential homes using water at multiple points simultaneously

Constant pressure water pumps or square tank water pumps are available to meet all applications ranging from 250 to 750 watts. They differ from round tank pumps in that the square tank features a pressure tank containing a rubber diaphragm filled with nitrogen gas. This creates internal pressure within the nitrogen tank to push water out, meaning the pump generates pressure immediately whenever water is turned on without having to wait for the water pressure in the pipe to drop to a certain level. Therefore, it delivers consistent and equal water pressure across every faucet during use. It also has a compact size that saves installation space, featuring a square shape, a white cover, a grey body, and a black base. However, newer models are currently released in the XX series with grey covers, which have been developed to be better than before in both performance and significantly quieter operation, allowing them to be placed next to a bedroom without noise disturbance.

Key features of Hitachi water pumps 

- Constant pressure with a specially designed Life-Extending Pressure-stabilized Unit that regulates water flow rate.
- Equipped with a nitrogen pressure tank that ensures steady water pressure without needing gas refills throughout its lifespan.
- All Hitachi water pump models are certified with the Level 5 Energy Efficiency Label and offer maximum efficiency according to industrial standards. 
- Strong, durable motor that prevents rust corrosion, backed by a 5-year motor warranty.
- Brass check valve closes tightly, eliminating air entry into the system; rust-resistant

Advantages and differences from conventional models of the Hitachi turbine-type 2-impeller water pump 

- New casing system developed from centrifugal pumps featuring 2 sets of impellers inside, meeting demands for both high power and ultra-quiet operation at noise levels below 49 dB
- Redesigned pump cover made of special "PPV0" material helps prevent the spread of fire
- The motor features a function that spins off foreign objects before entering the motor body to extend its service life.
- Stronger and constant pressure, suitable for large houses with simultaneous water usage at more than 8-9 points

How to maintain a Hitachi water pump 

1. Observe pump operation, such as whether water pressure flows strong and normally, whether the sound is normal, and whether the pump cuts in and out properly.
2. You should open the cover to check the interior for any leaks.
3. Prevent any leaks inside the house. If leaks are left unattended for a long time, the water pump will work harder and more frequently, overloading the motor unnecessarily and increasing electricity costs.
4. Always close the faucet completely right after use.
5. Check the cleanliness of the water in the water tank to prevent debris, dirt, and sand from entering the pump.
6. Build a sun and rain shelter to extend its service life.

How to install a Hitachi square tank water pump

Water pump installation equipment
- PVC pipe cutter scissors, saw
- Pipe wrench
- PVC pipe glue or solvent cement
- Ball valve
- Check valve 
- Tee fitting
- Elbow fitting
- Male straight connector 
- Straight connector size 
- PVC pipe 
- Teflon thread seal tape 

The water pump should be installed with a dual system: using water boosted by the pump, and bypassing the pump directly in case of a power outage or tap water interruption.

- Prepare the area for placing the water tank and the pump; there should be a roof to protect from sun and rain for a longer service life.
- Place the water pump as close to the water tank as possible for maximum efficiency.
- Connect the pipe from the water meter by first shutting off the meter valve, then connect a tee fitting to split the flow into the water tank and directly into the house.
- Run the pipe into the water tank, installing 1 ball valve to shut off the water for maintenance, and properly install the float valve inside the water tank.
- Screw straight threaded adapters into the tank's water outlet and the pump, wrapping Teflon tape clockwise around the threads about 10–15 turns. 
- Connect the pipe to the ball valve properly, then install the pipe line from the water tank to the water pump, with the ball valve positioned between the water tank and the water pump.
- Then connect the water outlet pipe with another ball valve, followed by a tee fitting connecting to the house and the municipal water supply
- Run a pipe from the meter and tank tee to connect to the tee in front of the water pump, with 1 check valve installed in between to prevent backflow when water is drawn from the water pump. 
- Connect the electrical wiring to the water pump while keeping the circuit breaker turned off.
- Open the water valves at the meter and at the tank inlet; wait until the water tank is completely full.
- Open the valve from the water tank to the pump while keeping the outlet valve closed.
- Turn on the water pump's circuit breaker, then wait a moment for the pump to run and then stop. 
- Open the outlet valve leading into the house, then test the pump's operation by opening and closing faucets inside the house. That completes the installation.

- Prepare the area for placing the water tank and the pump; there should be a roof to protect from sun and rain for a longer service life.

- Place the water pump as close to the water tank as possible for maximum efficiency.

- Connect the pipe from the water meter by turning off the meter's water valve first, then connecting with a tee fitting to divert water to the tank and directly into the house.

- Run the pipe into the water tank, installing 1 ball valve to shut off the water during maintenance, and properly connect the float valve inside the water tank.

- Connect the straight union connector to the water tank outlet and the pump unit, wrapping Teflon tape clockwise around the threads for about 10-15 turns.

- Connect the pipe to the ball valve properly, then install the pipe from the water tank to the water pump, placing the ball valve in between the water tank and the pump.

- Then connect the outlet pipe with another 1 ball valve, followed by a tee fitting connecting to the house and the main water supply.

- Open the water outlet valve leading into the house, then check by turning faucets on and off inside the house to test the pump's operation. This completes the installation.