If your campervan or motorhome water pump is running but no water reaches the taps, the pump may have lost its prime.
This commonly happens after:
- The fresh-water tank has run empty
- The vehicle has been driven with a low water level
- The system has been drained for winter
- A filter or pipe has been removed
- Air has entered the pump’s inlet side
- A valve has been left in the wrong position
In many cases, the pump is not faulty. It is simply drawing air instead of water and cannot create enough suction to pull water from the tank.
However, a pump that repeatedly refuses to prime may indicate a blocked filter, loose fitting, split suction pipe, closed valve, damaged pump diaphragm or a problem with the fresh-water tank outlet.
At WeConvert, we diagnose campervan and motorhome water-system faults for customers across Blackburn, Darwen and surrounding Lancashire. We inspect the tank, pump, inlet pipework, filters, valves and electrical supply before recommending replacement parts.
Quick Water-Pump Priming Guide
| Symptom | Possible causes |
|---|---|
| Pump runs but no water reaches any tap | Empty tank, airlock, closed valve, blocked inlet or suction leak |
| Water spits from the tap and then stops | Air in pipework, low tank level or pump losing prime |
| Pump primes only when the tank is full | Pump mounted too high, weak pump, restricted pipe or air leak |
| Pump works after driving but not before | Water movement temporarily covering the tank outlet or moving trapped air |
| Pump sounds unusually fast | Pump is running dry or drawing air |
| Pump sounds strained or slow | Blocked filter, low voltage, damaged pump or restricted pipe |
| Pump primes but quickly loses pressure | Leak, faulty non-return valve, loose fitting or pump fault |
| One tap works but another does not | Local blockage, closed valve, kinked pipe or faulty tap |
| Cold tap works but hot tap does not | Water-heater valve, drain valve, airlock or hot-side restriction |
| Pump will not run at all | Electrical supply, fuse, switch, wiring, pressure switch or pump-motor fault |
These symptoms provide a starting point rather than a confirmed diagnosis. More than one problem can create the same behaviour.
What Does “Priming” a Water Pump Mean?
Priming means filling the pump and its inlet pipe with enough water for the pump to begin drawing consistently from the fresh-water tank.
A typical campervan water system includes:
- Fresh-water tank
- Tank outlet
- Isolation or drain valve
- Inlet pipe
- Strainer or filter
- Water pump
- Accumulator, where fitted
- Hot- and cold-water pipework
- Taps, shower and appliances
Most campervan pressure pumps are designed to draw water from a nearby tank, but they still have practical limits.
They can struggle where:
- The pump is mounted too far above the tank
- The inlet pipe contains a large amount of air
- A fitting allows air to enter
- The tank outlet is uncovered
- The filter is blocked
- The suction pipe is kinked or collapsing
- The pump has been damaged by running dry
A pump may sound as though it is operating normally while moving only air.
First Check: Is There Enough Water in the Tank?
This sounds obvious, but tank gauges are not always accurate.
A control panel may show:
- One quarter full
- Half full
- A single illuminated level
- A percentage based on simple internal probes
These readings can be affected by:
- Dirty level sensors
- Vehicle parked on a slope
- Tank shape
- Water moving while driving
- Faulty wiring
- Incorrect calibration
- Sensor position
A tank can contain some water without the outlet remaining submerged.
This is particularly common where the vehicle is:
- Parked on a slope
- Braking or accelerating
- Driving with a low water level
- Using a shallow or irregularly shaped tank
- Fitted with a side outlet rather than a bottom outlet
Add a meaningful amount of clean water before attempting to prime the system.
Do not repeatedly run the pump based only on the control-panel reading.
1. The Fresh-Water Tank Has Run Empty
Running the tank completely empty introduces air into:
- Tank outlet
- Pump inlet
- Filter
- Pump chamber
- Hot- and cold-water lines
- Water heater
Once air enters the inlet side, the pump may take longer to begin drawing water again.
A simple priming attempt may involve:
- Fill the fresh-water tank sufficiently.
- Confirm the tank drain is closed.
- Switch on the water pump.
- Open one cold tap fully.
- Allow the pump a short period to draw water.
- Close the tap once the flow becomes steady.
- Repeat at the remaining cold taps.
- Prime the hot side afterwards, following the heater manufacturer’s procedure.
Do not allow the pump to run dry continuously for several minutes.
If no water begins moving after a short attempt, stop and investigate the inlet side.
2. The Water Level Is Too Low for the Tank Outlet
A tank may contain several litres of water while its outlet intermittently draws air.
This can happen where:
- The outlet sits above the lowest part of the tank
- The vehicle is leaning away from the outlet
- Water moves away from the pickup while travelling
- The tank has internal baffles
- The outlet pipe has been positioned poorly
This can explain a pattern where:
- The pump works when the tank is full
- The pump loses prime when the level falls
- Air appears at the taps after driving
- The pump runs continuously after cornering or braking
Parking on level ground and adding more water may restore operation temporarily.
If the issue occurs regularly, the tank outlet and pipe routing may need to be assessed.
3. Air Entered the System While Driving
Driving with a low tank level can move water away from the outlet and allow air into the suction pipe.
Once the pump draws air, you may notice:
- Spluttering taps
- Pump running faster
- Uneven water flow
- Pump failing to switch off
- Air bubbles in transparent pipework
- Water flow returning briefly and then stopping
This is likely similar to the problem many owners experience after travelling with a partly empty tank.
Switching the pump off while driving can prevent it repeatedly trying to repressurise a system that has drawn air. However, a travel switch does not correct an underlying suction leak or poorly positioned tank outlet.
If the pump frequently loses prime despite a reasonable tank level, the system should be inspected.
For a related fault, read Why Does My Campervan Water Pump Keep Running?.
4. A Tap Has Not Been Opened During Priming
The pump needs somewhere to push the trapped air.
If every tap is closed, pressure can build unevenly while air remains trapped in the pipework.
When priming:
- Start with one cold tap
- Open it fully
- Allow air and water to escape
- Wait for a steady flow
- Close it
- Repeat at each outlet
The outlet closest to the pump may prime first, but this is not always the best point to remove every air pocket.
The hot-water side can take longer because the water heater may need to fill before water reaches the hot taps.
Do not operate an electric water-heating element until the heater is correctly filled with water.
5. The Fresh-Water Tank Drain Valve Is Open
A drain valve may have been left open after:
- Winterisation
- Cleaning
- Tank maintenance
- Frost protection
- Plumbing work
- Previous storage
Depending on the design, water may:
- Drain directly onto the ground
- Return to another part of the system
- Allow air to enter
- Prevent pressure from building
Check:
- Fresh-water tank drain
- Internal pipe drain points
- Water-heater drain valve
- Frost-protection valve
- External drain taps
A water-heater drain valve can prevent the hot-water system from filling even where the cold taps work normally.
Do not force a valve closed if it is frozen, damaged or obstructed.
6. An Isolation Valve Is Closed
Some installations contain valves for:
- Tank outlet
- Pump inlet
- Pump outlet
- Water heater
- External shower
- Winter drain
- Second water tank
- Filling or transfer system
A valve may have been closed intentionally during maintenance and not reopened.
Check that valve handles align with their intended flow direction.
Do not rely solely on handle position where the valve is old or damaged. The internal mechanism may no longer move with the handle.
Where several unlabelled valves are fitted, photograph their original positions before changing anything.
7. The Pump Inlet Filter Is Blocked
Many pressure pumps have a small strainer or transparent filter fitted on the inlet side.
It may collect:
- Plastic swarf from the tank
- Sediment
- Limescale
- Biofilm
- Debris
- Sealant
- Pipe fragments
- Tank-manufacturing residue
A restricted filter can prevent the pump from drawing enough water to prime.
Possible symptoms include:
- Pump sounds strained
- Water flow is weak
- Pump primes only when the tank is full
- Flow improves briefly after the filter is moved
- Debris is visible inside the clear housing
Before opening the filter:
- Switch off the pump.
- Isolate or drain the water supply where necessary.
- Place a towel or container beneath it.
- Note the direction and seal arrangement.
- Clean it according to the manufacturer’s instructions.
- Refit the seal correctly.
- Check carefully for leaks and air entry.
A poorly reseated filter bowl or O-ring can become a suction leak and make the priming problem worse.
8. The Filter Seal Is Drawing Air
The pump’s inlet side may draw air through a fitting without leaking visible water.
This is an important point.
Because the inlet side is under suction, a loose joint may pull air inward rather than allowing water to drip outward.
Possible leak points include:
- Filter bowl
- Filter O-ring
- Threaded fitting
- Push-fit connector
- Hose clamp
- Tank connection
- Pump inlet connector
- Damaged pipe
Signs include:
- Air bubbles in clear pipe
- Pump repeatedly losing prime
- Flow returning when a fitting is pressed
- Pump working only with a full tank
- No visible water leak
Inspect and reseat accessible inlet fittings carefully.
Do not overtighten plastic pump connectors. Excessive force can crack the fitting or pump housing.
9. A Suction Pipe Is Loose, Split or Damaged
The section between the fresh-water tank and pump must remain airtight.
A small split can prevent priming even where the pipe does not visibly leak.
Check for:
- Loose hose clips
- Split flexible hose
- Cracked push-fit pipe
- Poorly inserted pipe
- Damaged tank connector
- Sharp bends
- Abrasion
- Pipe rubbing against metal
- Freeze damage
- Previous temporary repairs
Damage may be hidden:
- Behind furniture
- Beneath the floor
- Inside insulation
- Near the tank outlet
- Under the vehicle
If the pump has recently become difficult to prime after another job was completed, consider whether the inlet pipe has been disturbed.
10. The Inlet Pipe Is Kinked or Collapsing
Flexible hose can flatten under suction if it is:
- Too soft
- Poorly supported
- Routed around a tight bend
- Trapped behind furniture
- Heated or aged
- Unsuitable for potable-water use
A kink may allow some water through but restrict the flow enough to prevent reliable priming.
The fault may change as:
- The vehicle moves
- The pipe warms up
- Stored items press against it
- The tank level changes
Use hose and pipe suitable for the pump, pressure, suction conditions and drinking-water application.
A domestic hose that appears to fit may not be appropriate for a campervan installation.
11. The Pump Is Mounted Too High Above the Tank
Self-priming pumps have a maximum recommended lift.
The pump may struggle where it is:
- Significantly above the tank outlet
- Separated by a long inlet pipe
- Connected through multiple restrictive fittings
- Drawing through a clogged filter
- Installed with air-trapping loops
A system may work when the tank is full because the water level is closer to the pump, then fail as the level drops.
The pump should normally be mounted:
- Within the manufacturer’s permitted suction height
- As close to the tank as practical
- In a dry and accessible location
- With suitable vibration isolation
- With an inlet route that avoids unnecessary high points
Do not relocate a pump without considering electrical access, ventilation, freezing risk and leak protection.
12. The Pipe Routing Is Trapping Air
A high loop in the inlet pipe can retain air.
This can happen where the pipe:
- Rises above the pump and falls again
- Loops around furniture
- Crosses over another component
- Has excessive spare length
- Was moved during conversion work
An air pocket on the suction side can make the pump repeatedly lose its prime.
The inlet route should generally be:
- Short
- Smooth
- Properly supported
- Free from tight bends
- Free from unnecessary high points
- Protected from crushing
A small amount of tidying can sometimes improve reliability substantially.
13. The Tank Outlet Is Blocked
Debris inside the tank can obstruct the outlet.
Possible material includes:
- Plastic drilling swarf
- Sealant
- Limescale
- Sediment
- Cleaning residue
- Foreign objects
- Algae or biofilm
- Damaged internal pickup pipe
The pump may draw a small amount of water and then stop as debris moves against the outlet.
Symptoms can include:
- Pump primes intermittently
- Flow changes after driving
- Filter repeatedly fills with debris
- Tank contains water but no water reaches the pump
- Water flows briefly when the pipe is disconnected
Do not probe blindly into a tank fitting with a metal object.
The tank may need draining, cleaning and inspecting through a suitable access point.
14. A Non-Return Valve Is Stuck
Some systems include a non-return valve to prevent water flowing backwards.
A valve may become:
- Stuck closed
- Restricted by debris
- Installed backwards
- Damaged by freezing
- Internally worn
- Jammed by limescale
This can prevent water reaching the pump or cause the system to lose prime after the pump stops.
Check the direction arrow where one is visible.
Do not remove a non-return valve permanently without understanding why it was fitted. It may protect the pump, tank, heater or filling system from reverse flow.
15. The Pump Has Been Installed Backwards
This is most likely after:
- A new pump has been fitted
- Pipework has been altered
- The pump has been removed for winter
- A self-build system has recently been completed
Most pumps have marked inlet and outlet ports.
If reversed, the pump may:
- Run normally
- Move little or no water
- Fail to build pressure
- Make an unusual sound
- Push air towards the tank
Check the flow-direction markings on the pump rather than assuming the port position from another model.
Electrical polarity should also be checked. Some pump motors may run in the wrong direction if connected incorrectly, while others include circuitry that prevents operation.
16. The Pump Is Receiving Low Voltage
A water pump can run without producing its normal performance if the voltage reaching it is too low.
Possible causes include:
- Leisure battery discharged
- Loose terminal
- Corroded fuse holder
- Poor earth or negative connection
- Undersized cable
- Damaged switch
- Excessive cable length
- Failing pressure switch
Symptoms may include:
- Pump sounds slow
- Pump struggles to prime
- Lights dim when the pump starts
- Pump works on hook-up but not off-grid
- Pump becomes hot
- Flow improves when the engine is running
The voltage should be checked at the pump while it is operating, not only at the battery with the pump switched off.
For wider electrical symptoms, read Campervan or Motorhome 12V Electrics Not Working?.
17. The Pump Diaphragm or Valves Are Damaged
A pressure pump normally contains internal diaphragms and small valves that create suction and move water.
They can become damaged by:
- Running dry for extended periods
- Freezing
- Debris
- Age
- Chemical contamination
- Excessive pressure
- Poor storage
A damaged pump may:
- Run continuously
- Fail to prime
- Produce weak flow
- Pulse unusually
- Leak internally
- Lose pressure quickly
- Sound different from normal
Some pumps have service kits available. Others are more economical to replace.
The correct decision depends on:
- Pump make and model
- Age
- Availability of parts
- Condition of the motor
- Overall installation quality
18. The Pump Has Frozen
Water remaining inside a pump can freeze and expand.
This can damage:
- Pump housing
- Diaphragm
- Filter bowl
- Pipe fittings
- Non-return valve
- Water-heater connections
Freeze damage may not become obvious until the system is refilled.
Possible signs include:
- Pump will not prime
- Water leaks from the housing
- Filter bowl is cracked
- Pump runs but creates no pressure
- Several fittings leak at once
- Fault appears after winter storage
Do not operate a frozen pump.
Allow the system to thaw naturally and inspect it for damage before switching it on.
19. The Water Heater Is Preventing the Hot Side From Priming
If cold water flows normally but no hot water reaches the taps, check the water-heating system.
Possible causes include:
- Heater drain valve open
- Frost-control valve open
- Hot-water isolation valve closed
- Air trapped in the heater
- Heater bypass valves set for winterisation
- Non-return valve stuck
- Hot pipe kinked
- Heater not filling
The heater may need to fill with several litres of water before a steady flow reaches the hot taps.
Keep a hot tap open while the heater fills, following the heater manufacturer’s instructions.
Do not switch on an immersion element or electric heater while the water cylinder is empty.
20. The Accumulator Is Not Usually the Cause of Failure to Prime
An accumulator smooths water flow and reduces rapid pump cycling.
It does not normally create the suction that draws water from the fresh-water tank.
An incorrectly charged or failed accumulator can cause:
- Pump pulsation
- Frequent cycling
- Uneven pressure
- Reduced stored pressure
It is less likely to cause a complete failure to prime.
If disconnecting or altering an accumulator appears to restore flow, the wider pipe layout, pressure setting and valve arrangement should be checked.
We will cover accumulator pressure in a separate guide within this water-system series.
21. The Pump Has an Internal Pressure-Switch Fault
The pressure switch normally starts the pump when pressure falls and stops it once the target pressure is reached.
A pressure-switch fault can cause the pump to:
- Run continuously
- Fail to start
- Stop too early
- Start and stop rapidly
- Operate only when tapped or moved
However, where the pump runs steadily but cannot draw water, the fault is more likely to involve the inlet side or internal pumping mechanism than the switch alone.
Do not adjust pressure-switch screws without the pump manufacturer’s procedure.
Incorrect adjustment can create excessive system pressure or prevent the pump from switching off.
A Safe Priming Procedure
The exact process depends on the installed pump and water heater, but the following is a sensible general approach.
Step 1: Add sufficient fresh water
Do not rely only on the tank gauge.
Step 2: Park the vehicle level
This helps keep the tank outlet submerged.
Step 3: Confirm drain valves are closed
Check:
- Tank drain
- Pipe drains
- Heater drain
- Frost valve
Step 4: Check isolation valves
Confirm the tank outlet, pump and heater valves are in their normal operating positions.
Step 5: Inspect the pump filter
Check for debris, loose fittings and a displaced seal.
Step 6: Open one cold tap
Open it fully so trapped air has somewhere to escape.
Step 7: Switch on the pump
Allow it to run briefly while listening for changes in sound.
Step 8: Stop if no water appears
Do not leave the pump running dry continuously.
Step 9: Check the inlet side
Inspect the tank outlet, filter, suction hose and pump inlet for restrictions or air leaks.
Step 10: Prime each cold outlet
Once water flows steadily, move to the next tap.
Step 11: Prime the hot-water side
Follow the water-heater instructions and confirm the cylinder is full before turning on any heating element.
Step 12: Check for leaks
Inspect:
- Pump
- Filter
- Fittings
- Heater
- Taps
- Drain valves
A fitting disturbed during priming may begin leaking once pressure builds.
Should You Suck Water Through the Tap or Pipe?
You may see advice suggesting that owners create suction manually by:
- Sucking on a tap
- Sucking through a hose
- Drawing water with a wet vacuum
- Pressurising the tank
We would not recommend using your mouth on potable-water pipework.
There are hygiene and contamination risks, particularly where the system has been stored or chemically treated.
Applying pressure to a tank can also damage:
- Tank seams
- Inspection covers
- Filler connections
- Vent pipes
- Pipe fittings
Where a pump cannot self-prime using the correct procedure, the underlying restriction, leak or pump fault should be found rather than forcing the system.
Can Running the Pump Dry Damage It?
Some diaphragm pumps can tolerate brief periods of dry running, but that does not mean they should be left running indefinitely.
Extended dry running can contribute to:
- Pump overheating
- Diaphragm wear
- Valve damage
- Reduced service life
- Battery drain
- Noise
- Failure to notice a leak or open drain
If the pump does not begin drawing water within a short period, switch it off and investigate.
Follow the run-dry guidance for the exact pump model.
Why Does the Pump Prime and Then Lose It Again?
If the pump primes successfully but loses water after sitting, common causes include:
- Air leak on the suction side
- Faulty non-return valve
- Loose filter bowl
- Loose tank connector
- Split inlet hose
- Tank outlet becoming uncovered
- Internal pump-valve fault
- Water draining back into the tank
This is different from an initial airlock.
A correctly sealed system should not normally require manual priming every time the vehicle is used.
Why Does the Pump Work Only When the Tank Is Full?
This strongly suggests one of the following:
- Pump mounted too high
- Weak pump
- Air leak on inlet side
- Restricted filter
- Tank outlet position
- Inlet hose routing problem
- Tank not venting correctly
A higher water level makes it easier for water to reach the pump.
Once the level falls, the pump must create greater suction and may expose a weakness in the installation.
Why Does Water Splutter From the Taps?
Spluttering normally means air is passing through the pipework.
Possible causes include:
- System recently drained
- Tank ran empty
- Pump not fully primed
- Low water level
- Loose inlet fitting
- Damaged suction pipe
- Water heater filling
- Tank outlet drawing air while travelling
Some spluttering is normal immediately after refilling.
It should settle once every outlet has been purged.
If air continues entering after several minutes, inspect the pump’s inlet side.
Why Does the Pump Keep Running After Water Returns?
Once the system is full and every tap is closed, the pump should build pressure and switch off.
If it continues running, possible causes include:
- Tap or shower left open
- Leak
- Air remaining in the system
- Open drain valve
- Faulty non-return valve
- Pressure-switch fault
- Pump unable to reach shut-off pressure
- Accumulator problem
- Water-heater filling
Read Why Does My Campervan Water Pump Keep Running? for the complete troubleshooting guide.
Safe Checks You Can Make Yourself
Before booking water-system diagnosis, you can normally check:
- Actual fresh-water level
- Whether the vehicle is level
- Tank drain position
- Water-heater drain or frost valve
- Pump isolation switch
- Visible pipe valves
- Inlet filter for debris
- Accessible fittings for looseness
- Visible inlet hose for kinks or damage
- Pump sound
- Whether cold or hot outlets are affected
- Whether the fault began after driving
- Whether the fault began after winter storage
- Whether the pump works on hook-up but not from the battery
- Whether any water leaks appear while the pump operates
Useful photographs include:
- Fresh-water tank
- Tank outlet
- Pump installation
- Pump label
- Inlet filter
- Valves
- Accumulator
- Water heater
- Pipe routing
- Control panel
- Any visible leaks or air bubbles
What Should You Avoid Doing?
Do not:
- Leave the pump running dry for a prolonged period
- Overtighten plastic pump fittings
- Use household sealant inside potable-water connections
- Increase pump pressure without checking the pipework
- Force frozen valves
- Switch on an empty water heater
- Pressurise a fresh-water tank without manufacturer approval
- Use your mouth to draw water through pipework
- Ignore a pump or wire becoming hot
- Replace the pump before checking the filter and inlet pipe
- Use unsuitable hose for drinking water
- Add chemicals without following the product instructions
Stop operating the pump if you notice:
- Burning smell
- Hot wiring
- Melting fuse holder
- Significant water leak
- Cracked pump housing
- Water entering electrical equipment
- Repeated fuse failure
- Pump motor becoming excessively hot
How We Diagnose a Water Pump That Will Not Prime
A structured diagnosis avoids replacing a pump that is still serviceable.
At our workshop serving Blackburn and surrounding Lancashire, the process may include:
- Confirming when the fault began
- Checking the fresh-water level and tank outlet
- Inspecting drain and isolation valves
- Examining the inlet filter
- Checking the suction pipe for air leaks
- Inspecting pipe routing and pump height
- Measuring pump voltage under load
- Testing water flow into the pump
- Checking the non-return valve
- Assessing the pump diaphragm and internal valves
- Checking the water-heater filling arrangement
- Pressurising the completed system and checking for leaks
We do not automatically replace the pump because it is running without producing water.
The cause may be a blocked filter, loose fitting, incorrectly positioned valve or air leak costing much less to correct.
Campervan and Motorhome Water-System Repairs Near Blackburn
WeConvert provides campervan and motorhome water-system installation, upgrades and fault finding for customers from Blackburn, Darwen, Accrington, Burnley, Rossendale, Bolton, Chorley, Preston and across Lancashire.
We can assess suitable issues involving:
- Water pumps not priming
- Pumps running continuously
- Weak water pressure
- Air in the taps
- Pump pulsation
- Fresh-water tanks
- Inlet filters
- Accumulators
- Water heaters
- Drain and frost-control valves
- Pipework leaks
- Damaged fittings
- Tank outlets
- Existing self-build plumbing
- Systems installed by another converter
Learn more about our campervan water systems and plumbing services.
For broader workshop repairs, visit Campervan and Motorhome Repairs and Fault Finding.
Frequently Asked Questions
Why is my campervan water pump running but no water comes out?
The pump may be drawing air because the tank is empty, the outlet is uncovered, the inlet pipe has a leak, the filter is blocked or a valve is closed.
Open one cold tap while attempting to prime the pump.
How long should a campervan water pump take to prime?
A correctly installed pump with water available at its inlet should normally begin moving water relatively quickly.
If it continues running without producing water, stop and investigate rather than leaving it running dry.
Can a water pump prime itself?
Many campervan diaphragm pumps are described as self-priming, but their ability depends on the suction height, pipe length, fittings, filter condition and whether the inlet side is airtight.
Why does the pump lose prime after driving?
Water may have moved away from the tank outlet, particularly where the tank level is low.
Air may also be entering through a loose suction-side fitting.
Should I switch the water pump off while driving?
Switching it off can prevent the pump running continuously if water moves away from the tank outlet or a pipe develops a leak.
It does not repair an underlying priming fault, but it is a sensible operating precaution in many installations.
Can a blocked filter stop a water pump priming?
Yes.
A heavily restricted inlet filter can prevent enough water reaching the pump to create suction and build pressure.
Can a pump draw air without leaking water?
Yes.
A loose suction-side fitting can pull air into the pipe without producing an obvious water leak.
Why does the pump work only with a full tank?
The pump may be mounted too high, the inlet may be restricted or leaking, or the tank outlet may become exposed as the water level falls.
Does an accumulator help a pump prime?
An accumulator smooths pressure and reduces pump cycling.
It does not normally solve an inlet-side priming problem.
Can low battery voltage stop the pump priming?
Yes.
The pump motor may run too slowly to create sufficient suction where voltage is low or there is excessive voltage drop.
Can freezing damage a campervan water pump?
Yes.
Water expanding inside the pump, filter or fittings can crack components and damage internal valves.
Can WeConvert inspect a water system installed by someone else?
Yes, subject to access and the condition of the installation.
We can assess factory-built motorhomes, professional conversions and self-build campervans.
Book Campervan Water-System Fault Finding Near Blackburn
If your campervan or motorhome water pump will not prime, send us:
- Vehicle make, model and year
- Type of conversion
- Water-pump make and model
- Fresh-water tank location
- Whether the tank is internal or underslung
- Whether the pump runs
- Whether any taps receive water
- Whether the fault affects hot, cold or both
- Whether the problem began after driving or winter storage
- Photographs of the pump, filter and pipework
- Details of any recent plumbing work
- Your postcode
We can then advise whether the vehicle should be booked in for water-system diagnosis.
Contact WeConvert to request campervan or motorhome water-pump fault finding near Blackburn.