Installation guide

Fitting SavvyTanks V3

A 12V feed, then as many of the sensors as you want: up to three water probes, a gas sender, a gas solenoid and two relays. Most of the afternoon goes on running probe cable rather than on anything difficult.

The SavvyTanks V3 module, a black box with rows of green screw terminals along its edges
The module. Power on one side, tanks and relays on the other, and nothing between it and the panel but wireless.

At a glance

Water tanks
Up to 3 - fresh, grey and black
Water probes
CBE PC200, ours or third-party
Gas
Any 0–90 or 0–95 ohm sender, either way round
Gas solenoid
Driven directly - the low current driver is built in
Relays
2, up to 10A each
Pairs as
TanksV3
Not compatible with
SavvyVan Lite panels

See SavvyTanks V3 - £90

Mounting it

The module is a serviceable part. It must be mounted where it can be reached, disconnected and removed without dismantling fixed furniture or bonded panels - for example in an electrical locker, under a seat, or behind a removable access panel. Every probe cable runs back to it, so settle where it goes before you run any.

Powering it

The module needs a 12V, 1A fused supply into the terminals marked +/−. They are labelled on the case.

Water probes

SavvyTanks works with CBE PC200 probes, whether you bought them from us or elsewhere.

Remove the white connector from the sender, and extend the cable if the run needs it. The probe terminals are marked Tanks 1 to 3, and any probe can go on any of them. The default is:

  • Tank 1 - fresh water
  • Tank 2 - grey water
  • Tank 3 - black water

You can change that on the panel later, so it is worth doing whatever makes the cable runs tidiest.

A CBE PC200 water probe with its white connector removed, showing three coloured wires
The probe with its connector off. The plastic cap on the far end stays where it is.

Wire by colour:

  • White → W
  • Brown → B
  • Green → G
A close-up of the SavvyTanks V3 terminals for tanks 1 to 3, each marked W, B and G
Each tank has three terminals, marked W, B and G. Same three colours, three times over.
The SavvyTanks V3 module with probe wires landed in the tank terminal blocks
Landed and tightened. Give each one a gentle tug before you close everything up.

Gas level

Any 0–90 or 0–95 ohm sender works, and the wiring is not polarity sensitive - the two wires from the sender go onto the terminals marked GAS either way round.

A close-up of the SavvyTanks V3 terminals marked GAS with two wires connected
Two wires, either way round. Gasit and Propex underslung tanks are the ones we see most, but any 0–95 ohm sender is fine.

Gas solenoid

The Ultra Low Current Driver is built in, so the module can open and hold a 12V solenoid on its own - no separate driver needed.

Connect the solenoid’s +/− to the Solenoid terminals.

The SavvyTanks V3 module with a gas solenoid wired to its Solenoid terminals
Solenoid straight onto the module. Tested with Gasit, Propex and Autogas 2000 tanks, and it works with any 12V solenoid.

Relays

Two relays, 10A each. They work by interrupting a single wire passing through them, so the pattern is the same whatever you connect.

A remote drain valve:

  1. Connect the valve’s live wire to your 12V feed, as its manufacturer specifies.
  2. Run the valve’s negative into one terminal of relay 1 or 2.
  3. Run the other terminal of that relay to ground.
The SavvyTanks V3 module’s row of green screw terminals, with the two Relay1 terminals circled in amber at the left-hand end
The relay sits in the negative line. Selecting the relay against a tank means tapping that tank on screen opens the valve.

Plumbing, a wiring diagram, and a second way to wire the valve - straight to one of the panel’s own switches - are in the drain valve guide.

Anything else 12V or 24V wires the same way, up to 10A per relay.

What the light is telling you

One LED on the module tells you where you are - check it before you go near the panel.

The lightWhat it means
Solid greenPowered up and booting. Give it a few seconds
Flashing blueBooted, and waiting to pair
Solid bluePaired to your panel. Nothing more to do
RedSomething is wrong - see troubleshooting
Nothing at allNo power reaching it - see troubleshooting

Pairing it

  1. On the panel, open Installer Settings, enter the passcode, and go to the device pairing screen - the one with Scan on the right.
  2. Wait for TanksV3 to appear under available devices. The list fills in by itself a few seconds after the page opens; tap Scan if it is slow to show.
  3. Tap the green + next to TanksV3. It appears in the saved list on the left.
The SavvyVan3 device pairing screen: an empty saved list on the left, and on the right, under the Scan button and a search box, TanksV3 with a Good signal rating and a green + beside it
TanksV3 under available devices, with its signal strength beside it. Tap the + and it joins the saved list on the left.

Setting up your tanks

Go back to Settings, then Tanks Settings, and enable SavvyTanks. On a Sargent, CBE or BCA version of the panel that is a dropdown rather than a switch - choose SavvyTanks from it.

Each tank has its own Enable switch. Turn on each one you physically connected, and set:

  • Type, on a water tank - fresh, grey or black.
  • Source, on the gas tank - which module reads the gas level. Tanks is SavvyTanks. If a Propex heater module is paired as well, Propex is offered too: choose whichever one your gas sender is wired to.
  • Capacity - so the screen can show litres as well as a percentage. Water tanks are in litres or gallons, the gas tank in kg.
  • Relay, on a water tank - if you attached one. Selecting it here is what makes tapping that tank on screen activate the valve.

The gas tank has no relay to choose: the solenoid links to it automatically.

The SavvyVan3 Tanks Configuration screen with SavvyTanks enabled: Water Tanks 1 to 3 set to Fresh Water 100 L, Gray Waste 70 L on relay 1 and Black Waste 40 L, and a Gas Tank with its source set to Tanks, 11 Kg and no relay
Tanks Settings. Only the tanks you enable appear on the main screen, so an unused probe input does not clutter it.

Using it

Tank levels appear on the main screen. With more than one configured they take turns every 5 seconds, and a red ring around a tank means its relay is active.

Tap the tank icon for the full page, where everything is visible at once and a tap toggles a configured tank.

The SavvyVan3 Tank Levels page: Fresh Water at 80% (80/100 L), Gray Waste at 40% (28/70 L), Black Waste at 20% (8/40 L) and LPG at 60% (7/11 Kg)
The tank page. Fresh, grey, black and gas together - which is the point of it.

Troubleshooting

Nothing in the list when you scan? Check the module’s 12V supply first.

No light is a supply problem, not a pairing one. Check the fuse and the feed before you rescan - it is the commonest reason a module never appears.

A red light means the module cannot do its job. Power it down, check the wiring against this guide, and power it back up. Still red? Tell us rather than working around it, and send the log files from the passcode screen.

Specification

Working voltage7–30V
Draw0.06A at 12V
Dimensions115 × 55 × 25 mm
Water tanksUp to 3
Relays2, up to 10A each

Warranty

SavvyTanks V3 carries our 12-month warranty. The free second year you get for registering is for the SavvyVan3 panel itself, so there is nothing to register for this one.

Questions people ask

Do the probes come with it?
No - the box holds the module alone. Probes are sized to your tank and start at £44, and you need one per water tank.
Should I take the cap off the end of the probe?
No. The plastic cap at the end stays on - it is part of how the probe works.
Can I use the relays for something other than tanks?
Yes. They will switch any 12V accessory up to 10A each. Plenty of people use one for a drain valve and the other for something else entirely.
I have a Sargent or CBE interface module. Can I use my existing water probe with SavvyTanks?
No - the probe in your van connects to the SavvyVan3 interface board’s own input, which is a separate path from SavvyTanks. SavvyTanks has its own terminals and uses CBE PC200 probes. You need new probes for it, one per tank you want to monitor. If you have a Sargent system, bear in mind the interface board reads your fresh water sender only - the grey waste indicator is not supported - so SavvyTanks with PC200 probes is also the way to add grey and black water monitoring.

Stuck on any of this? Get in touch - we would rather help than have you guess.

Last checked over: 19 September 2026

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