Alde 3020 not heating

NissaB

On a recent trip in our newly acquired 2019 T@B 400, we could not get the Alde heater to work. We did get hot water, but no heat. I think the problem may be with the indoor temperature sensor. On the standby screen it shows the temperature to be 158 F. Clearly it was not over 60 F inside. Understand that the heat will not come on until the indoor temp is below the setting, which is 72 F. Have tried resetting the system and rebooting by removing shore power and turning off the battery. When starting system back up it still says indoor temp is 158 F. Have not figured out where the sensor is located. Any thoughts on this? 

pthomas745

I think I saw this on the FB page?  And the discussion came up about the setting for the "room sensor?"  Did you try that ?  Page 20 of the manual.

PS: Welcome to the Forums!

NissaB

We did look at that, but the room sensor icon is greyed out and we were unable to do anything.

MuttonChops

Two things to try:

1,   Review each of the menu screen items with manual handy . . . is something set to an odd condition "like timed operation" or circulation pump always off.

2.  If nothing jumps out as the issue; consider using the Service Menu to reset the unit to Alde Factory conditions  (I'm not sure but do suspect that's nuCamp's factory settings.) 

If you have Hot Water the Adle is working - - - you just need to find out why the 'cabin heating' circulation pump is not running.

pthomas745

@NissaB I was hoping that simple room sensor or the "system reset" would work.  I don't thing this issue has ever been reported.

Most of the simple Alde error messages can be cleared by: turning off the Alde, unplugging from shore power, and then turning off the battery switch.  Once the 12V power has been removed, the panel/Alde clears the error and you can go about seeing if the Alde will work, troubleshoot, etc.  So, that is one option to try.

The Alde panel is connected directly by a cable from the panel to the Alde circuit board.  There have been instances of that cable getting "crimped" or otherwise knocked around.  It is very easy to find.

This thread has a picture of the three main cables going into the Alde circuit board.  Easy to spot. (Your Alde panel cable may be different: my cable in an older model has a "Molex" type connector in that panel slot).

So, have a good look at this cable and make sure it is secure.

https://tab-rv.vanillacommunity.com/discussion/10894/alde-3020-system-question

NissaB

Everything looks secure with the wiring. I was not aware that the battery should be off when connecting to shore power and am sure we did not do that. Will make sure of that in the future. However the fuses were not blown. Is it possible that the sensor was damaged from not turning off the batter before connecting?

pthomas745

The sure sign that the fuse/fuses on the Alde itself are "blown" is the control panel simply does not work.  If you can see the panel, then the fuses are "probably" not the issue. 

You will see in the manual several different "error messages" the Alde seems to randomly throw out.  Gas Failure, Overheat Red Fail, etc.  To clear them, just go through that procedure to turn everything off and then turn off the battery disconnect switch.

PS: there were big changes to the Aldes after the 2018 model: the fuses and Alde ground were re-arranged and the "blown fuses" that caused such consternation pretty much disappeared.  Still a good practice to have the Alde "off" when you are done with it, but the Alde 3020 rarely (it seems) blows the single Alde fuse. 

You could just have a bad panel.  If you can, I would go through the screens listed on page 2-12 of the manual see that everything under "Installed Functions" is unchecked except the Alde flow.

NissaB

Everything is unchecked except Alde Flow.

qhumberd

So we have the same system and if I understand the facts here the standby screen circled below is showing? 158 deg ? 

If this is right I think the control panel is bad but you should be able to force the heating circulating pump on on the Tool menu by pressing the symbol on R and finding the circulation pump symbol and change to Cont operation 

This is also used when flushing the glycol to force the pump to run, so you can see if it is working. As the indoor temp is only able to be changed via the offset function, not sure how to fix that, but if the glycol is heating and you have hot water, forcing the circulating pump on should give you heat.

See if that works 

beachman77

new owner, how does water get into domestic hot water tank?  how do you drain and fill domestic hot water tank?

Jilong

beachman77 said:

new owner, how does water get into domestic hot water tank?  how do you drain and fill domestic hot water tank?

This might be better off as a separate thread since it's not directly related to the OP's question, but water goes from the water pump through the bypass valve into the Alde tank and out into your plumbing. There should be drain valves for hoses coming out of the bottom of the trailer by the Alde unit to drain the tank. I have a 2018 Tab 400 so I have separate valves I flip for these things. I think newer models use the Nautilus system so you'd have to follow the pictures to do the bypass and drain.

bergger

I was going to suggest the same thing that @qhumberd recommended.  Set the circulation pump to cont.  This will make the pump work continuously and not just operate based on the thermostat.  This will also allow you to circulate the hot glycol and get some heat.  It will also let you know if you have an air block as the the fluid will not circulate through the expansion tank.   An air block will also prevent the heat from working.  But with that 158 degree temp showing it seems like there is an issue with the thermostat.  Remove the silver bezel around the display and see if the thermostate is loose or in contact with anything.  If that is not the case them most likely the thermostat is bad and needs to be replaced.  I also recommend contacting Truma/Alde and speaking with them.  

NissaB

The circulation pump has been set to CONT. I hear a faint humming but get no heat. When I switch to THERM the humming stops. Removed the bezel cover but didn't see anything unusual. I am reluctant to try to pull the display from the box and not sure what I'd see if I did. Will also look at the Alde manual on dealing with the air block. and will take your suggestion and call Alde on Monday. Thanks to all of you all for your help.

Grumpy_G

The humming would be the pump, how long did you have it running ? It takes a while to heat up the radiators/convectors spread through the trailer. Check if the rubber hose going to the convectors warms up with the pump running, that's the quickest way to check. 

Edit: In the automotive world sensors show abnormal low temps when the circuit is open and abnormal high temps when the circuit is shorted. 158F indoor temp makes me think shorted sensor. Does the 400 have an external sensor ? I know my older 320 doesn't. 

GregChris

If you turn the battery off on shore power, and the power goes out, happens more than you think, you going lose your fridge. I always thought of my battery as shore backup.

bergger

With the pump on Cont does the glycol flow through the loop? You can tell this if the glycol is churning in the expansion tank. 

qhumberd

Also you can locate the circulation pump that is now humming on CONT mode and find the speed control (usually a red dial) it points 1 (lowest to 5 highest). It is good that it is humming but if there is an air block in the heating loop you can get that out by turning the pump to 5 and check the reservoir. It should churn the glycol as @bergger mentioned. This will often clear the air in the loop and restore normal function. Then turn the pump back to about 2-3. I agree that your thermostat is likely malfunctioning so a call is in order to Truma/Alde on that.

pthomas745

We may be a little off track talking about the pump, and air, and bleeding, etc.  The photo below is what NissaB sees when the Alde is on.  The Alde thinks the temperature inside the trailer is 158 degrees.  If I remember, the highest temperature you can set for heat on my Alde is 85 degrees.  So, the Alde settings for "Therm" will never have any effect for running the pump.

The temperature sensor is located in the control panel, so this might indicate the control panel has failed (although it certainly seems to be working) or, specifically, the thermostat section of the panel has failed. Which would still mean to replace the panel, since everything is so closely integrated.

We seem to have gone through everything else, except, maybe, to try the temperature offset in the Settings.  Look for section 15 in the 3020 manual, on Page 20.  Can the temperature be adjusted in that section?

Last: we have seen in the past how oddly the temp sensor in that panel can react to drafts from the AC space in the 3020, etc.  I would think that trying to influence the temp sensor in the panel with an ice pack in an attempt to cool it down and see if that 158 degree readout changes.  An ice pack may make the LCD screen a little wonky, but if you can get enough cold air onto the panel, we would hope the temp may change.

@NissaB, once you get the bezel off, there are 4 screws that hold the guts of the panel on the wall.  There is really nothing behind it except for a couple of cables, the ones that you may have looked at down on the Alde itself a few days ago.

And...sure enough, I searched around for "Alde control panel replacement" and there was an incident just like this in 2019.

https://tab-rv.vanillacommunity.com/discussion/9961/alde-temp-showing-158-degrees-fixed

bergger

@pthomas745 I definitely agree that it is a control panel/thermostat issue and that is the direction @NissaB needs to go in.  I was was just giving a suggestion to run the pump on continuous as a way to make sure the rest of the heating system actually works and as a means to get heat in the cabin if needed prior to a thermostat fix.  I certainly recommend calling Truma/Adle USA and discussing the issue with them.  

You can try messing with the temp offset as well.  But it only offsets plus or minus 10 degrees F so not sure if that will help.  But maybe adjusting that will trigger something to make it work? 

pthomas745

A "trigger" was what I was thinking, too. 

NissaB

So, before reading the message from pthomas745 at 7:20 am, I called Alde and they said that the reading of 158F on the sensor meant it was defective. But it is a non-replaceable item, so the whole controller needed to be replaced. I ordered the part for $220.66 and came back to tell everyone the solution. That's when I noticed the new response. I immediately went out to the T@B and took the controller cover off. Sure enough, there was a small piece (the temperature sensor) touching the spring on the inside of the controller. I moved it very slightly, turned on power and the temperature reading was 88F. That's 2F above the highest temperature setting (86F), so I'll just wait until it cools off this evening to test the system. Alde did confirm that the heating system would not work if the temperature sensor was reading above 86F.



The thermal sensor is just to the left of the spring. The sensor was touching before I moved it. We now think this could have happened when the controller was bumped and the cover came off. The cover was put back not knowing what it should look like, so had no idea that the sensor was being shorted out.

I'll follow up later to confirm this solved the problem. Thanks again everyone.

bergger

Yep that has happened before and glad you fixed it. Though I know of one person in the past that was advised by alde to first check that issue, sensor in contact with something, its too bad you did not get that response before being told to order a new controller.

NissaB

Forgot to mention that I was able to cancel the order for the controller. They were very cooperative about that.

bergger

Good news. And thanks for posting the pic of the sensor and spring on the controller.

qhumberd

This thread earns a star! Another reason I love this forum.

NissaB

Just tested and everything is working like it should. Thanks to this group for the tremendous support. I know we've learned a lot about the Alde system.

pthomas745

Total luck on finding that older post.  I was scrolling through a Google image search for "control panel replacement" and had to do a double take when I saw the subject of that 2019  thread.