If your Truma AquaGo isn’t producing hot water, don’t immediately assume the water heater has failed.

The AquaGo needs several things before it can operate properly:

Water flow. Propane. 12-volt power. And a control system that’s ready to operate.

Problems with any one of these can leave you with cold water or an error code.

The AquaGo also has a few quirks of its own. Air trapped in the plumbing, a control panel that needs to be “woken up,” or a unit accidentally placed into Clean mode can sometimes look like a much more serious failure.

Start with the simple checks before assuming there’s an internal problem.

Quick Summary

If your Truma AquaGo isn’t working:

Check the control panel and error code.
Make sure the AquaGo is turned on.
Check the propane supply.
Verify that other propane appliances operate.
Check the RV’s 12-volt power.
Open a hot-water faucet and verify good water flow.
Clean restricted faucet aerators and shower heads.
Purge air from the hot-water plumbing.
If you’re using city water, try the fresh-water tank and RV water pump.
Check whether the AquaGo has accidentally entered Clean mode.

If those checks don’t identify the problem, the error code can help determine what to investigate next.

Safety Stop

The Truma AquaGo combines propane, electricity, hot water and a combustion system.

There are several things an RV owner can safely check, but internal gas-system and electrical repairs should be handled by someone qualified to perform them.

Stop and have the heater inspected if:

You smell propane.
You see soot around the exhaust.
Wiring appears burned or damaged.
You see evidence of overheating.
Water has entered electrical components.
The burner behaves abnormally.
You’re uncomfortable performing a particular test.

Never bypass a safety device or use an open flame to look for a propane leak.

Truma AquaGo Error Code Quick Reference

Depending on which control system your RV uses, AquaGo faults may appear differently.

With the CP plus digital control, the fault can appear directly on the display.

With many AquaGo installations using the analog rotary control, a fault is indicated by the LEDs. The red LED behind the AquaGo’s exterior access panel flashes a combination of short and long flashes corresponding to the fault.

Truma specifically highlights the following as common AquaGo codes. (Truma)

Code	What It Means	What to Check First
E1	No flame detected	Propane supply, tank valve, whether other propane appliances work
W27	Circulation pump running dry	Water supply and air trapped in hot-water lines
W29	Too much heating power required	Too many hot-water fixtures being used simultaneously
W30	Risk of freezing	AquaGo temperature has fallen below about 27°F / 3°C
W31	Decalcification complete	Not a failure — cleaning cycle has finished

These aren’t the only AquaGo fault codes, but they’re among the codes Truma says its customer-care team encounters most often. (Truma)

Check First: Do You Have Water Flow?

Turn a hot-water faucet fully on.

Does the water flow normally?

The AquaGo burner automatically starts when hot-water flow exceeds approximately 0.4 gallons per minute (1.5 L/min). The heater then adjusts its burner output according to water flow and incoming-water temperature. (Truma)

If flow is weak, check:

Faucet aerators
Shower head
Water filters
Fresh-water level
RV water pump
Campground water supply
Kinked hoses
Plumbing restrictions
Winterization/bypass valves

Try Another Faucet

This is one of the easiest diagnostic tests.

If the AquaGo operates normally from the kitchen faucet but doesn’t operate properly from the bathroom sink, don’t immediately blame the water heater.

Compare the flow from the two fixtures.

A plugged aerator or restricted fixture can reduce water flow considerably.

Check for Air in the Water Lines

Air trapped in the plumbing is particularly worth checking on an AquaGo.

Truma identifies trapped air as a common cause of the W27 circulation-pump-running-dry fault.

Their recommended owner-level check is simple:

Go through the RV and open each hot-water faucet individually.

If you hear air or see the water sputtering, let the faucet continue running until the flow becomes steady.

Repeat this at the other hot-water fixtures.

Once you’ve purged the air, try the AquaGo again. (Truma)

This is especially worth checking after:

De-winterizing
Draining the RV
Running the fresh tank empty
Plumbing repairs
Replacing filters
Reconnecting the water supply

Try the Fresh-Water Tank and RV Water Pump

This is a useful test with almost any RV on-demand water heater.

If you’re connected to campground water and the AquaGo isn’t behaving properly:

Fill the fresh-water tank.
Shut off or disconnect city water as appropriate.
Turn on the RV water pump.
Open a hot-water faucet.
See whether the AquaGo operates normally.

If the heater suddenly works properly, you’ve learned something valuable.

The AquaGo itself may be fine.

Campground water pressure or flow may be contributing to the problem.

This test is particularly useful when a water heater works perfectly at one campground but becomes unreliable at another.

Check the Propane Supply

If water flow is good but the AquaGo doesn’t ignite, check the propane.

Make sure:

There’s propane in the tank.
The propane service valve is open.
Other propane appliances operate.
The RV hasn’t recently run out of propane.

Try another propane appliance such as the stove.

If nothing else will operate on propane either, start troubleshooting the RV’s propane supply rather than the AquaGo.

Truma E1 — No Flame Detected

E1 means the AquaGo attempted to ignite three times but couldn’t establish a flame.

Truma recommends starting with the propane tank: verify that there’s fuel and that the service valve is open. (Truma)

Also check whether another propane appliance operates.

If the RV recently ran out of propane, there may be air in the propane system.

If you have confirmed a good propane supply but E1 repeatedly returns, the problem may require further diagnosis of the heater’s ignition, burner, flame detection or gas system.

That’s a good point to stop owner-level troubleshooting rather than begin dismantling combustion components.

Truma W27 — Circulation Pump Running Dry

A W27 indicates that the circulation pump isn’t generating the expected water flow.

One common cause is air trapped in the water system.

Open each hot-water faucet individually and allow any trapped air to escape until you have steady water flow.

Then try the AquaGo again. (Truma)

Also make sure:

The RV has water.
The water pump is operating if you’re using the fresh tank.
City water is actually flowing.
Plumbing valves are correctly positioned.
Nothing is restricting the water supply.

Truma W29 — Too Much Hot-Water Demand

This one is interesting because the heater may not actually be broken.

A W29 means the AquaGo is operating at its maximum heating output but can’t achieve its normal outlet temperature because the RV is demanding too much hot water.

The AquaGo can produce up to 60,000 BTU/h, but there’s still a limit to how much water it can heat simultaneously. (Truma)

For example:

Someone is showering.

Meanwhile, someone else starts washing dishes with hot water.

The AquaGo may no longer have enough heating capacity to maintain its normal outlet temperature.

Turn off the second hot-water fixture and see whether normal operation returns.

Sometimes the solution to a water-heater fault is simply:

One hot-water user at a time.

Truma W30 — Risk of Freezing

A W30 warning means the temperature inside the AquaGo has dropped below approximately 27°F (3°C). (Truma)

Take this warning seriously.

If the RV is going into freezing conditions and the AquaGo isn’t adequately protected, drain the water heater according to Truma’s winterization procedure.

The AquaGo uses an Easy Drain Lever. Truma instructs owners winterizing the unit to drain it, release the yellow lever, remove the filter and allow the water to drain. Importantly, Truma says not to reinstall the filter for winter storage. (Truma)

Some AquaGo installations may also have Truma’s optional electric antifreeze kit.

Truma W31 — Decalcification Complete

This one sounds worse than it is.

W31 isn’t telling you that the heater failed.

It means the AquaGo has successfully completed its decalcification cycle. (Truma)

Return the AquaGo to its normal Eco or Comfort operating mode according to the control system installed in your RV.

AquaGo Stuck in Clean Mode?

Here’s another problem that can look like a failed water heater.

Truma says accidentally getting an AquaGo stuck in Clean mode is one of the more common troubleshooting calls its customer-care team receives. (Truma)

If the AquaGo is in Clean mode, the burner isn’t supposed to operate normally.

That means you can turn on the hot water and wonder why you’ve suddenly lost heat when nothing has actually failed.

Truma’s recovery procedure involves completing the required flushing process and then resetting the AquaGo back into Eco or Comfort mode. Depending on the stage of the cleaning process, flushing can take 15 minutes or more. (Truma)

Follow Truma’s procedure for your particular control panel rather than repeatedly cycling the heater.

Control Panel Doesn’t Light Up?

Before assuming the controller has failed, try waking it up.

Truma notes that an AquaGo analog control knob may sometimes need to be turned slowly between the on and off positions—potentially more than once—before the amber indicator illuminates and the system responds. (Truma)

It’s a simple check, but exactly the kind of thing worth trying before digging deeper into the electrical system.

Check the 12-Volt Power

Even though the AquaGo heats water with propane, it still requires 12-volt DC electrical power.

The controls, ignition system and other components depend on it.

Truma specifies nominal 12 VDC operation, with normal electrical consumption below 2.5 amps during operation. (Truma)

Look around the RV.

Are the lights unusually dim?

Are other 12-volt appliances acting strangely?

Is the battery discharged?

Has a fuse blown?

If several 12-volt systems are behaving abnormally, investigate the RV’s electrical supply before assuming the AquaGo itself has failed.

Water Gets Warm but Not Hot Enough

First determine whether you’re asking the AquaGo to supply several fixtures simultaneously.

A W29 fault specifically points toward excessive hot-water demand.

Turn off other hot-water faucets and test one fixture by itself.

Also consider the temperature of the incoming water.

The AquaGo varies burner output between approximately 20,000 and 60,000 BTU/h according to demand and is designed for an outlet temperature around 120°F (49°C). (Truma)

Extremely cold incoming water combined with high flow or multiple fixtures creates a much greater heating demand.

Hot Water Temperature Keeps Changing

Start by looking at water flow.

Is the campground pressure fluctuating?

Is the RV water pump cycling strangely?

Is an aerator restricted?

Is another person opening and closing a faucet elsewhere in the RV?

The AquaGo uses a temperature-stabilizing mixing vessel and modulating burner specifically to minimize temperature fluctuations, so substantial or persistent swings deserve investigation. (Truma)

Try operating one hot-water fixture at a time and see whether the temperature stabilizes.

Don’t Forget the AquaGo Filter

The AquaGo has a reusable filter cartridge designed to protect internal components.

That filter is also involved in draining, winterization and the AquaGo’s decalcification process. (Truma)

If you’re troubleshooting water-flow problems, particularly after maintenance or de-winterizing, make sure the filter and Easy Drain Lever are correctly installed for normal operation.

And if the heater is calling for decalcification, don’t ignore it indefinitely.

Scale accumulation can affect water-heater performance over time.

Eco vs Comfort Mode

Depending on the AquaGo model and controls, you may have Eco and Comfort modes.

Don’t confuse the operating mode with a fault.

The AquaGo Comfort Plus adds a circulation pump and recirculation system designed to provide hot water more quickly at the fixtures. (Truma)

Knowing which AquaGo model you have can therefore matter when you’re interpreting pump operation or circulation-related behavior.

When to Book Service

It’s time to bring in a qualified RV technician or Truma service provider if the AquaGo has good water flow, adequate propane and good 12-volt power but still won’t operate.

Service is also appropriate when fault codes repeatedly return after you’ve corrected the obvious external cause, the heater repeatedly fails to establish a flame, you smell propane, you see soot around the exhaust, there’s evidence of electrical damage, or you’re uncomfortable continuing the diagnosis.

Don’t bypass switches, sensors or other safety devices to make the heater operate.

Service Call Prep

Before booking service, write down:

Your exact AquaGo model
The error code
The short/long LED flash sequence, if applicable
Whether the burner attempts to ignite
Whether other propane appliances work
Whether the problem affects every faucet
Whether water flow is strong
Whether you’ve purged air from the plumbing
Whether it works using the RV water pump
Whether it fails only on city water
Whether the unit is in Eco, Comfort or Clean mode
Whether the RV was recently winterized or de-winterized
Whether the AquaGo was recently decalcified

Those details can make the technician’s job considerably easier.

Why Water Flow Still Matters

The AquaGo is more tolerant of low flow than some on-demand RV water heaters, but it still needs water movement before it can operate.

Truma says the burner starts when flow exceeds approximately 0.4 GPM. (Truma)

So I would still start with water.

But with an AquaGo, I would add another question very early:

Is there air trapped in the system?

A simple plumbing problem can produce a circulation fault that makes the water heater look much more complicated than it really is.

Frequently Asked Questions

Why won’t my Truma AquaGo ignite?

Check water flow, propane and 12-volt power first. If you have an E1 fault, Truma specifically recommends checking that there’s adequate propane and that the tank service valve is open. (Truma)

What does E1 mean on a Truma AquaGo?

E1 means the heater attempted ignition three times without establishing a flame. Start with the propane supply before assuming there’s an internal ignition failure. (Truma)

What does W27 mean on a Truma AquaGo?

W27 indicates that the circulation pump isn’t generating water flow. Trapped air is a common cause, so purge the hot-water lines and make sure the RV has an adequate water supply. (Truma)

What does W29 mean?

The AquaGo is being asked to provide more heating power than it can deliver. This can happen when multiple hot-water fixtures are being used simultaneously. Reduce hot-water demand and try again. (Truma)

What does W31 mean?

Good news: W31 means the decalcification process has finished. It isn’t a water-heater failure. (Truma)

Why won’t my AquaGo work after I accidentally selected Clean?

The unit may need to complete its cleaning/flush sequence before returning to normal operation. Truma identifies accidentally entering Clean mode as a common customer-support issue and provides a specific recovery procedure. (Truma)

Why does my Truma AquaGo work with the RV pump but not campground water?

That strongly suggests investigating campground water flow or pressure. Using the fresh tank and RV pump is a useful way to separate an external water-supply problem from a water-heater problem.

Written by Dan Harvickson (Founder of Last Mountain) RV Specialist

Truma AquaGo Not Working? Troubleshooting & Error Codes