MITSUBISHI WP-505R2 Automatic Water Pump Round Tank 500W

Automatic Water Pump, Round Tank MITSUBISHI WP-505R2 Power 500 Watts
The most popular round-tank automatic water pump known for its durability and delivery power. With a 500W motor providing exceptionally high water flow, it features Mitsubishi's proprietary technology for quiet and stable operation. The pressure tank is made of extra-thick steel with anti-rust coating both inside and outside. Ensure complete safety with an automatic shut-off system when overheating occurs.

Features

High-Power Motor: High-power 500W motor delivers strong and continuous water pressure even when multiple taps are opened simultaneously
Anti-Rust Tank: Specially coated pressure tank both inside and outside prevents rust and extends service life
Water Temp Control: Water temperature control system helps prevent damage to the pump body and plastic parts when run dry
Thermal Protector: Automatic shut-off system when the motor overheats to prevent motor burnout
Compact Design: Standard round tank shape, easy to install, space-saving, and hassle-free maintenance
Safe & Silent: Quiet operation meeting Mitsubishi standards and uses materials safe for consumption

Applications

Suitable for large residences with 3-4 stories
Performs well with multiple water outlets used simultaneously (approx. 1-10 points), such as multiple bathrooms, rain showers, or water heaters
Suitable for small commercial buildings or dormitories that require consistent water pressure

Specifications

Motor power: 500 W
Max. suction head: 8 m
Max. head: 24 m
Max. flow rate: 82 L/min (at 14 m head)
Flow rate at 12 m head: 70 L/min
Pressure Switch: On 2.4 / Off 2.8 (kgf/cm2)
Suction/Discharge pipe size: 35 mm (1-1/4 in)
Protection standard: IP44

Mitsubishi round tank or pressure tank water pump

Another water pump brand that has been popular in Thailand for a long time. Features a large pressure tank structure in yellow with a black base, enclosed with an Aluminum Frame Cooling Fan material that helps prevent animals or insects from getting inside and causing noise. The pump head assembly made of copper alloy is durable and rust-free.  The specially designed tank is welded with Seam Welding technology, withstanding high pressure without leaking, and is coated with special non-toxic paint both inside and outside to provide excellent rust prevention. The tank cover is made of special flame-retardant, strong, and durable plastic.  Proprietary air charger rapidly replenishes air to reduce frequent cycling issues. In addition, it features a backflow prevention system and a tank pressure control system, operating automatically based on the opening and closing of water taps. Equipped with a special ceramic seal gasket that is extra thick and durable. Enhanced safety with a ground wire ensures safety during installation and operation. Certified to ISO standards.

Which type of round tank water pump is suitable for how many stories of a house?

Suitable for general houses with few taps in use that require high delivery pressure 
How many watts of water pump should be used?
1-story house: wattage from 100-200 W should be used
2-story house: wattage from 250-300 W should be used
For a 3-4 story house, dormitory, or commercial building, a wattage of 300 watts or higher should be used.
However, some houses still experience insufficient water pressure despite purchasing according to the recommended wattage for each story. This might be because the house has many rooms or family members requiring higher-than-normal water usage. Therefore, in addition to calculating the wattage based on the number of stories, the actual water consumption in the household must also be taken into account.

Maintenance tips for long-lasting water pump use

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.

Basic troubleshooting for common issues with Mitsubishi round tank water pumps

1. Mitsubishi round tank pump frequently turns on and off
Assume first that it might be caused by a leak at the water pump or in the household piping system. The check is simple: just close the outlet valve and observe whether the pump still operates. If the frequent cycling stops → this indicates a leak inside the house. But if it persists, it indicates a leak at the pump itself, which may be caused by a worn mechanical seal or a leaking, deteriorated pressure tank. 

2. Mitsubishi round tank pump does not work
First, check what type of failure it is: power is connected and there is a humming sound but the motor doesn't rotate, or it is completely silent.

3. Mitsubishi water pump does not work, power is on with a humming sound, but the motor does not rotate 
1. It may be caused by a deteriorated, shorted, or burned capacitor. To check, turn off the circuit breaker, remove the machine cover using a Phillips screwdriver to unscrew the cover, then open the condenser/capacitor cover. Then inspect the capacitor (the small black rectangular unit) to see if it is swollen or burned. If abnormal, take it as a sample or check its microfarad (uF) rating and visit a water pump spare parts shop to buy a replacement by splicing the wires. 
2. Caused by damaged bearings or a jammed impeller. To check, turn off the breaker, use a flathead screwdriver to turn the shaft at the rear end of the motor to see if it rotates normally, or remove the motor cooling fan cover and rotate the fan by hand to see if it turns smoothly. If not, it could be caused by damaged bearings that are rusted out or foreign objects trapped inside the impeller.

4. Mitsubishi water pump does not work, does not turn on, and is completely silent; this may be due to no power coming in.
This can be caused by a broken power cord or a faulty pressure switch. To check, verify whether power is reaching the water pump by removing the machine cover, followed by opening the motor capacitor cover. Then use a test light screwdriver to check. If power is normal, it could be a faulty pressure switch. To check: turn off the breaker, open the pressure switch cover with a Phillips screwdriver, and check if the switch is stuck. Fix it by replacing with a new pressure switch.

5. Mitsubishi water pump does not work due to excessive temperature
Current models have an automatic cut-off system to prevent motor burnout. The solution: stop using the water pump, turn off the breaker, wait for the motor to cool down, and then turn it back on.

Mitsubishi round tank water pump makes abnormal noise. Usually, abnormal noises stem from several causes, but most commonly: 

1. The cooling fan is deteriorated, cracked, broken, or has insects inside causing abnormal noise. Solution: Use tools such as a Phillips screwdriver and snap ring pliers. Use the screwdriver to remove the fan cover screws, use the pliers to remove the retaining snap ring, pull out the old fan, insert the new fan, and reassemble as before. 
2. Small stones, sediment, or gravel have slipped into the water impeller. Solution: Use a socket or size 8 T-wrench to loosen the screws and open the impeller cover, being careful not to tear or damage the front pump gasket, then clean out all foreign objects and reassemble as before. 
3. Damaged or worn bearings. Symptoms: continuous loud noise throughout operation.  This may be caused by rust resulting from a worn shaft seal that allowed water into the bearing, or bearings cracked from prolonged service life. The solution must be handled by a skilled technician; it is recommended to contact a nearby technician to inspect it.