Written By: Cary Alburn
When I bought my 2018 Ascent back in October 2017, I had never had an instant water heater. I had heard that my Truma AquaGo Comfort Plus was pretty good; I soon found that what I heard was correct.
But I also learned that it is a tad finicky—it actually requires that its instructions be followed! Read the manual, follow the manual, and you’ll love it. Don’t read the manual, don’t follow the manual, and you’ll be frustrated.
Truma also makes a straight Comfort. The difference: the Plus has a 3rd line that circulates water—hot water goes from the water heater to the farthest outlet through the red water line and back to the water heater through the white line by using an internal water pump. There’s almost no wait for hot water at the outlets. Pleasure-Way has installed the Plus in all models since 2017.
The Truma AquaGo Comfort Plus on my 2018 Ascent.
One feature that is part of the system is the little hybrid tank, which helps maintain a consistent temperature. Unlike other brands of instant water heaters, the Truma Comfort models are less subject to not firing the burner if the water pressure or flow is low. Because it has a more robust burner than most other brands, it’s almost impossible to run water through it so fast that it can’t properly heat it. The common complaints about other brand instant water heaters don’t happen with a Truma AquaGo.
The little hybrid tank is located behind the yellow drain on the left.
The manual has an appendix, which has a list of potential problems with how to identify them. It’s a decoder, so that when the Truma faults, you can decode the problem. With the older round control, watch the flashing red LED located outside, near the on/off switch. The new digital screen control (used when the coach has other Truma appliances) states the error number. To determine the error with the older round control, you must go outside and watch the dots and dashes that the red LED shows. I found it easier to video them and look at the recording, to match the code to the appendix decoder. Caution: the older round control will flash a yellow LED to tell you that there is a problem—that’s all it does—it does NOT tell you what the problem is.
Directly above the on/off/on switch is a green LED that shows there is power. Below the switch is the red LED which flashes to decode any faults
To use the Truma, it’s really important to follow these steps IN ORDER.
FIRST: Make sure all of the valves behind the Truma, accessed from the panel behind it inside the coach, are properly set. Don’t think “summer mode” or “winter mode”. “Properly set” means that the red, blue, and white valves must be “on”—the handles are parallel to the red, blue, and white water lines. The bypass valve, which has a red line on one side and a blue line on the other side, must be “off”; the handle is perpendicular to the line.
Again: All “on” except the bypass, which must be “off”. The single most common user error is failing to turn “on” the white circulating line valve. The second most common error is to fail to turn “off” the bypass valve.
SECOND: Make sure that the propane is “on”. This seems basic, but just recently, I thought I had a Truma problem, but in reality I had failed to turn on the propane while setting up at a campsite. When I admitted that error on social media, I learned that many others have made the same mistake. Now turn on the outside switch on the Truma—it’s the previously shown rocker switch, and only the gnomes that designed it understand why “on” can be either way, up or down. “Off” is midway between “on” and “on”. Wait to make sure the green LED lights, a few seconds after switching “on”. If the green LED does not turn on, check that the coach’s 12v power switch inside has been turned on.
THIRD: Go inside, and turn on the water pump, or if you’re on city water, make sure it’s turned on. THIS IS IMPORTANT—THERE MUST BE WATER PRESSURE INSIDE THE TRUMA. Then turn on the inside control. With the round rotary switch, you have two “on” choices, but you cannot control the temperature. With the new digital display, you can adjust the temperature. But you still have two modes, Eco and Comfort. Eco mode does not circulate the water through the 3rd line, so the farthest outlets won’t get hot water until the water has been run for awhile. Comfort is the circulating mode. Eco is also cooler than Comfort. Theoretically Eco, because its cooler, burns less propane. But because the Truma is pretty efficient, I doubt anyone would notice a difference in propane usage. I do not use the Eco mode.
This is the older round control.
The new digital control, used when there is more than one Truma appliance installed. It is located under the drivers side ottoman in the van models
When you turn on the Truma to Comfort mode, its internal pump will run for a while to circulate the water. When it’s first started, especially the first time after de-winterizing the water system, it often cavitates a little. If you failed to turn on the pump or provide city water pressure so that there’s no water pressure inside the Truma, it will continue to cavitate, the water heater will “fault”, and then it will shut down.
When the water heater faults and shuts down, for whatever reason, the older rotary control yellow LED will flash (but remember, it’s not a code) or the digital panel will show error, and it’s time to start over. Turn off the inside control, go outside; if you need to determine the code from the flashing red LED, do so. Then turn off the outside switch, wait about 10 seconds, and then turn on the outside switch again. Wait for the green LED to light. Correct whatever the fault was, and then turn on the inside control again.
Again—things must be done step by step IN ORDER, or the water heater won’t work correctly.
What about the other positions of the rotary switch, or other settings of the digital panel? The “winterize” mode requires a $200 accessory, which replaces the filter. It’s available on the Truma Amazon site. It’s easy to install—takes about 5 minutes. A plug device, which is part of the winterize accessory, is installed outside to block air from entering the intake and exhaust of the Truma. When the control is set to “winterize” mode, that accessory heats up and the internal water pump runs continuously. It provides enough heat to protect the Truma from freezing while the vehicle is being driven and also protects the hot water line and circulating line. The outside plug device must be removed to use the Truma when stopped.
The “winterize” accessory does NOT protect the Truma from freezing in lieu of proper winterization. It’s purpose is to protect the Truma when the user has water in the system and is being driven in below freezing weather. When the user has water in the system and is stopped, turning on the Truma (yellow plug removed, propane on, inside control set to “Comfort”) will protect the Truma from freezing.
The last position on the rotary control (“clean”) is for decalcification, and the digital panel has a similar setting. The standard filter is filled with 6 decalcification tablets (available on Amazon), inserted into its cavity, and the decalcification process is started by turning the control to that position. Decalcification should be done annually, or before 1500 gallons—the Truma will shut down at 1500 gallons if decalcification hasn’t been done, and that’s the only thing that can be done at that time. Even full time users are unlikely to hit 1500 gallons in a year, so doing it annually is best.
Decalcification takes time (allow 3 hours) and a lot of water. Truma says 8 gallons; my experience is that it’s about double that amount. If you’re decalcifying using your onboard water source, make sure it’s full before you start the decalcification process. The manual’s instructions for decalcification are clear, so I won’t repeat them here.
CAUTION: if you accidentally start a decalcification cycle, it’s nearly impossible to get it out of that mode, except by running prodigious amounts of water through the Truma. So be careful—that could be extremely annoying, especially if you’re boon docking without a water source to refill your water tank.
Winterization of the Truma could not be easier! Open the yellow drain, remove the filter, let the water drain out, and you’re done. Do NOT reinsert the filter! That mistake may cause what little water remains in the Truma to freeze and break something—usually the hybrid tank or fittings leading to it. Store the filter somewhere—I suggest the kitchen sink.
It is not necessary or desirable to pump RV antifreeze into the Truma. When you winterize the rest of the plumbing, be sure to turn “off” the red, blue, and white valves and turn “on” the bypass valve.
Your Truma AquaGo Comfort Plus is one of the best appliances you can have. With a minimum of maintenance, annual decalcification and proper winterization, it will give you reliable hot water for many years.