Water Pump WP7LPM 12 V drinking water pump, 7 l/min, 1.38 bar - 4-chamber with pressure switch and strainer
- 12 V diaphragm drinking water pump, 4 chambers, 7 l/min, 1.38 bar. Pressure switch, check valve, self-priming up to 1.8 m, thermal protection. Strainer and 2 hose barbs included. For motorhomes, caravans, boats.
Water Pump WP7LPM is a 12 V diaphragm drinking water pump with a blue 4-chamber head. It delivers up to 7 l/min, and the built-in pressure switch starts it when a tap opens and stops it at 1.38 bar. For water systems in motorhomes, caravans, boats and cabins.

Key features
- 4 chambers - smooth flow and quiet running
- pressure switch: the pump starts when pressure drops and stops when the tap closes
- check valve prevents backflow
- self-priming up to 1.8 m vertical lift
- short dry running (up to 30 s) does not damage the pump
- thermal protection with automatic restart after cooling

In the box
- pump with power leads
- strainer
- 2 hose barbs
- rubber anti-vibration feet

Installation
- on a flat, solid surface in a dry, ventilated place (e.g. under the floor or in a cabinet) with easy access for service
- ideally level with or below the tank; above the tank it primes up to 1.8 m vertically, and a horizontal inlet line can be up to 9 m
- any position; if mounted vertically, the head points down
- do not overtighten the feet - the rubber mounts are there to isolate vibration and noise
- at least 30 cm of 1/2" (13 mm) flexible pressure hose on both ports
- strainer before the pump on the inlet side; fittings are hand-tightened, no PTFE tape or sealant

System diagram
The pump draws water from the tank and feeds the taps, shower and water heater. An accumulator tank after the pump reduces pulsation and frequent pump cycling.
Electrical connection
- a dedicated circuit with a breaker or fuse, total circuit current up to 15 A
- wire size for a 10% voltage drop at 12 V (length = battery to pump and back):
- 0-7.6 m: 1.3 mm² (16 AWG)
- 7.6-15.2 m: 2.1 mm² (14 AWG)
- 15.2-21.3 m: 3.3 mm² (12 AWG)
- 21.3-33.5 m: 5.3 mm² (10 AWG)
- maximum current draw: 4.3 A

Use and winter
- intermittent duty - not designed for continuous running
- for fresh and sea water, weak acids and alkalis, liquid temperature up to 60°C
- sanitise the system with a bleach solution, then flush with clean water
- before winter drain the tank, pipes and pump; never use automotive antifreeze, only non-toxic potable water antifreeze

Parts and spares
The parts that wear most are the diaphragm and the bearing. The matching spare is the head repair kit for 4-chamber pumps (bearing, diaphragm).
Photos and drawings


Other Water Pump products
- 4-chamber pump WP10LPM, 10.6 l/min, 3.1 bar - higher flow version
- head repair kit for 4-chamber pumps (bearing, diaphragm) - fits this pump
- 0.75 l pressure accumulator tank - fitted after the pump
- 1/2" NPT water strainer - fitted before the pump
- small 2-chamber pump SWP38LPM, 3.8 l/min, 2.4 bar
- 2-chamber pump SWP31LPM, 3.1 l/min, 4.8 bar
Technical data
| Parameter | Value |
|---|---|
| Model | WP7LPM |
| Type | diaphragm, 4-chamber, with pressure switch |
| Voltage | 12 V DC |
| Flow | 7 l/min |
| Shut-off pressure | 1.38 bar |
| Max. current draw | 4.3 A |
| Self-priming | up to 1.8 m |
| Dry running | up to 30 s |
| Ports | 1/2" NPT male |
| Liquid temperature | up to 60°C |
| Motor | permanent magnet |
| Protection | thermal, with automatic restart |
| Duty | intermittent |
| Use | drinking water, motorhome, caravan, boat |
| Certificate | CE |
Questions and answers
Does the pump switch off by itself?
Yes. The pressure switch stops it when the tap closes and pressure reaches 1.38 bar, and restarts it when pressure drops.
Is a strainer included?
Yes, a strainer and 2 hose barbs are included.
Can I mount the pump above the tank?
Yes, it primes up to 1.8 m vertically. Mounting level with or below the tank is still best.
Which repair kit fits?
The head repair kit (bearing, diaphragm) for the 4-chamber pumps WP7LPM and WP10LPM.
Manufacturer
Carbon Zorro Sp. z o.o., ul. Humańska 8, 02-789 Warsaw, Poland.















