Question 1

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: The fresh water tank has run dry.. Check, fill.

Question 2

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: Pump not primed. Refer to manufacturer's instructions

Question 3

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: The pump wired in reverse. Check the wiring is correct, following the pump manufacturer's own instructions.

Question 4

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: A pipe has come loose at the pump's inlet or outlet.. Check connections

Question 5

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: Pipes restricted by kinks. Check pipe runs

Question 6

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: The pump's inlet or outlet pipe is blocked.. Check for the blockage, starting with the fresh water tank itself.

Question 7

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: An in-line filter or the pump's own filter is blocked.. Dismantle and clean

Question 8

No water comes out of any tap when it's turned on, even though the pump is running.

Accepted Answer

Possible cause: There's an air leak in the pipe feeding into the pump.. Look for air bubbles in the pipe and fit a clip to seal the joint.

Question 9

Pump does not run

Accepted Answer

Possible cause: Pump or tap wired incorrectly. Refer to pump/tap manufacturer's instruction

Question 10

Pump does not run

Accepted Answer

Possible cause: Pump fuse blown. Check the wiring connections are sound, then fit a fresh fuse of the correct rating.

Question 11

Pump does not run

Accepted Answer

Possible cause: Battery disconnected. Check connections

Question 12

Pump does not run

Accepted Answer

Possible cause: Pump seized or overheated. Refer to manufacturer's servicing instructions

Question 13

Pump does not run

Accepted Answer

Possible cause: On a pressure-controlled pump, the pressure-sensing switch itself may have failed.. Refer to manufacturer's servicing instructions

Question 14

Pump does not run

Accepted Answer

Possible cause: On a switched-tap system, the tap's own switch may have failed.. Refer to manufacturer's servicing instructions

Question 15

The cold tap runs normally, but the hot tap's flow is weaker.

Accepted Answer

Possible cause: The feed pipe into the water heater has been connected to its outlet by mistake.. Refer to installation instructions

Question 16

The cold tap runs normally, but the hot tap's flow is weaker.

Accepted Answer

Possible cause: Blockage in hot pipeline. Disconnect pipes and inspect

Question 17

The cold tap runs normally, but the hot tap's flow is weaker.

Accepted Answer

Possible cause: A kink in the heater's inlet or outlet pipe is restricting the flow.. Check for kinks and re-route the pipe if needed, making sure the hose fitted is the recommended type.

Question 18

The cold tap runs normally, but the hot tap's flow is weaker.

Accepted Answer

Possible cause: Hot tap is not connected. Refer to installation instructions

Question 19

The cold tap runs normally, but the hot tap's flow is weaker.

Accepted Answer

Possible cause: Hot tap failed or blocked. Disconnect and inspect

Question 20

The cold tap runs normally, but the hot tap's flow is weaker.

Accepted Answer

Possible cause: Heater non-return valve jammed. Seek service attention

Question 21

Both the hot and cold taps have reduced flow.

Accepted Answer

Possible cause: A kink in the cold water pipe is restricting the flow.. Check and re-route if necessary

Question 22

Both the hot and cold taps have reduced flow.

Accepted Answer

Possible cause: Blockage in cold pipe line. Disconnect the pipework just after the first Y-connector and trace it through to the tap, checking as you go.

Question 23

Both the hot and cold taps have reduced flow.

Accepted Answer

Possible cause: Cold tap not connected. Refer to installation instructions

Question 24

Both the hot and cold taps have reduced flow.

Accepted Answer

Possible cause: Cold tap failed or blocked. Disconnect and inspect

Question 25

Both the hot and cold taps have reduced flow.

Accepted Answer

Possible cause: On a Carver Crystal unit, the cartridge may have reached the end of its life.. Replace cartridge

Question 26

Both the hot and cold taps have reduced flow.

Accepted Answer

Possible cause: A low battery is making the pump run more slowly than normal.. Check how much charge is left in the battery - see the electrical supply section for guidance.

Question 27

Water flows from the hot tap but the cold tap's flow is reduced.

Accepted Answer

Possible cause: Newly-fitted taps may themselves be restricting the flow.. Disconnect them and confirm their bore is at least 6.3mm.

Question 28

Water flows from the hot tap but the cold tap's flow is reduced.

Accepted Answer

Possible cause: Pump needs servicing. Refer to pump servicing instructions

Question 29

Water flows from the hot tap but the cold tap's flow is reduced.

Accepted Answer

Possible cause: The pump's own filter, or an in-line filter if one is fitted, may be partly blocked.. Dismantle and clean if necessary

Question 30

Water flows from the hot tap but the cold tap's flow is reduced.

Accepted Answer

Possible cause: A kink at the pump's outlet is restricting the flow.. Check and re-route if necessary.

Question 31

Water flows from the hot tap but the cold tap's flow is reduced.

Accepted Answer

Possible cause: Water leak. Check all water connections

Question 32

Water difficult to drain

Accepted Answer

Possible cause: 'Y' connectors fitted incorrectly. Refer to installation instructions

Question 33

Water difficult to drain

Accepted Answer

Possible cause: Kinked pipework is restricting the flow.. Check and re-route if necessary

Question 34

Water difficult to drain

Accepted Answer

Possible cause: Bore size difference in taps. Fit taps that share the same bore size.

Question 35

Water difficult to drain

Accepted Answer

Possible cause: Drain plug partially blocked. Remove plug entirely

Question 36

Water difficult to drain

Accepted Answer

Possible cause: With the hot taps shut, air can't get into the hot water system to let it drain.. Open taps

Question 37

Water difficult to drain

Accepted Answer

Possible cause: Loops hanging in pipe runs. Refer to installation instructions.

Question 38

Reduced flow from either tap

Accepted Answer

Possible cause: Hot water is feeding back into the cold line - usually because a mixer tap or a single combined hot/cold outlet is in use.. Fit a non-return valve into the cold supply, close to the tap.

Question 39

The cold tap runs warm instead of cold.

Accepted Answer

Possible cause: On a pressurised system, the pump's switching pressure is set too high.. Refer to water supply note

Question 40

The cold tap runs warm instead of cold.

Accepted Answer

Possible cause: On a switched-tap system, the pump is delivering more flow than the tap itself can pass.. Refer to water supply note

Question 41

Water pump runs on for more than 5-10 seconds after closing all taps

Accepted Answer

Possible cause: Possible leak in the system. Check the whole water system for leaks without delay, and make a habit of powering the pump down from its control panel every time you leave the vehicle.

Question 42

Aerated water from a tap

Accepted Answer

Possible cause: There may be a leak on the pump's suction side.. Look for a leak where the pump draws water in and repair as needed.

Auto-Trail Water System

Master Troubleshooting & Diagnostics Matrix

Frequently Asked Questions

Q: How do I drain down the water system for winter or storage?

Error Code / Indicator	Symptom / Meaning	Possible Cause	Step-by-Step DIY Fix	Suggested Actions
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	The fresh water tank has run dry.	Check, fill.	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	Pump not primed	Refer to manufacturer's instructions	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	The pump wired in reverse	Check the wiring is correct, following the pump manufacturer's own instructions.	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	A pipe has come loose at the pump's inlet or outlet.	Check connections	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	Pipes restricted by kinks	Check pipe runs	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	The pump's inlet or outlet pipe is blocked.	Check for the blockage, starting with the fresh water tank itself.	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	An in-line filter or the pump's own filter is blocked.	Dismantle and clean	DIY Safe
`N/A`	No water comes out of any tap when it's turned on, even though the pump is running.	There's an air leak in the pipe feeding into the pump.	Look for air bubbles in the pipe and fit a clip to seal the joint.	DIY Safe
`N/A`	Pump does not run	Pump or tap wired incorrectly	Refer to pump/tap manufacturer's instruction	DIY Safe
`N/A`	Pump does not run	Pump fuse blown	Check the wiring connections are sound, then fit a fresh fuse of the correct rating.	DIY Safe
`N/A`	Pump does not run	Battery disconnected	Check connections	DIY Safe
`N/A`	Pump does not run	Pump seized or overheated	Refer to manufacturer's servicing instructions	DIY Safe
`N/A`	Pump does not run	On a pressure-controlled pump, the pressure-sensing switch itself may have failed.	Refer to manufacturer's servicing instructions	DIY Safe
`N/A`	Pump does not run	On a switched-tap system, the tap's own switch may have failed.	Refer to manufacturer's servicing instructions	DIY Safe
`N/A`	The cold tap runs normally, but the hot tap's flow is weaker.	The feed pipe into the water heater has been connected to its outlet by mistake.	Refer to installation instructions	DIY Safe
`N/A`	The cold tap runs normally, but the hot tap's flow is weaker.	Blockage in hot pipeline	Disconnect pipes and inspect	DIY Safe
`N/A`	The cold tap runs normally, but the hot tap's flow is weaker.	A kink in the heater's inlet or outlet pipe is restricting the flow.	Check for kinks and re-route the pipe if needed, making sure the hose fitted is the recommended type.	DIY Safe
`N/A`	The cold tap runs normally, but the hot tap's flow is weaker.	Hot tap is not connected	Refer to installation instructions	DIY Safe
`N/A`	The cold tap runs normally, but the hot tap's flow is weaker.	Hot tap failed or blocked	Disconnect and inspect	DIY Safe
`N/A`	The cold tap runs normally, but the hot tap's flow is weaker.	Heater non-return valve jammed	Seek service attention	Professional Intervention Required
`N/A`	Both the hot and cold taps have reduced flow.	A kink in the cold water pipe is restricting the flow.	Check and re-route if necessary	DIY Safe
`N/A`	Both the hot and cold taps have reduced flow.	Blockage in cold pipe line	Disconnect the pipework just after the first Y-connector and trace it through to the tap, checking as you go.	DIY Safe
`N/A`	Both the hot and cold taps have reduced flow.	Cold tap not connected	Refer to installation instructions	DIY Safe
`N/A`	Both the hot and cold taps have reduced flow.	Cold tap failed or blocked	Disconnect and inspect	DIY Safe
`N/A`	Both the hot and cold taps have reduced flow.	On a Carver Crystal unit, the cartridge may have reached the end of its life.	Replace cartridge	DIY Safe
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`N/A`	Both the hot and cold taps have reduced flow.	A low battery is making the pump run more slowly than normal.	Check how much charge is left in the battery - see the electrical supply section for guidance.	DIY Safe
`N/A`	Water flows from the hot tap but the cold tap's flow is reduced.	Newly-fitted taps may themselves be restricting the flow.	Disconnect them and confirm their bore is at least 6.3mm.	DIY Safe
`N/A`	Water flows from the hot tap but the cold tap's flow is reduced.	Pump needs servicing	Refer to pump servicing instructions	DIY Safe
`N/A`	Water flows from the hot tap but the cold tap's flow is reduced.	The pump's own filter, or an in-line filter if one is fitted, may be partly blocked.	Dismantle and clean if necessary	DIY Safe
`N/A`	Water flows from the hot tap but the cold tap's flow is reduced.	A kink at the pump's outlet is restricting the flow.	Check and re-route if necessary.	DIY Safe
`N/A`	Water flows from the hot tap but the cold tap's flow is reduced.	Water leak	Check all water connections	DIY Safe
`N/A`	Water difficult to drain	'Y' connectors fitted incorrectly	Refer to installation instructions	DIY Safe
`N/A`	Water difficult to drain	Kinked pipework is restricting the flow.	Check and re-route if necessary	DIY Safe
`N/A`	Water difficult to drain	Bore size difference in taps	Fit taps that share the same bore size.	DIY Safe
`N/A`	Water difficult to drain	Drain plug partially blocked	Remove plug entirely	DIY Safe
`N/A`	Water difficult to drain	With the hot taps shut, air can't get into the hot water system to let it drain.	Open taps	DIY Safe
`N/A`	Water difficult to drain	Loops hanging in pipe runs	Refer to installation instructions.	DIY Safe
`N/A`	Reduced flow from either tap	Hot water is feeding back into the cold line - usually because a mixer tap or a single combined hot/cold outlet is in use.	Fit a non-return valve into the cold supply, close to the tap.	DIY Safe
`N/A`	The cold tap runs warm instead of cold.	On a pressurised system, the pump's switching pressure is set too high.	Refer to water supply note	DIY Safe
`N/A`	The cold tap runs warm instead of cold.	On a switched-tap system, the pump is delivering more flow than the tap itself can pass.	Refer to water supply note	DIY Safe
`N/A`	Water pump runs on for more than 5-10 seconds after closing all taps	Possible leak in the system	Check the whole water system for leaks without delay, and make a habit of powering the pump down from its control panel every time you leave the vehicle.	DIY Safe
`N/A`	Aerated water from a tap	There may be a leak on the pump's suction side.	Look for a leak where the pump draws water in and repair as needed.	DIY Safe