Alde T@B 400 (2019) not circulating heat

Davids

I have a 2019 T@B 400 with the Alde 3020 and Alde Flow. Last winter when I was preparing for a winter trip, I ran the Alde heating system, which up until then worked fine, for a couple of days to check things, and came home to see gylcol on the pavement, which came out of the automatic airbleeder I believe. Nucamp provided me with a new airbleeder under warranty, but since then I have not been able to get the system to work. After replacing the airbleeder I topped up the gylcol and have bleed the lines, using the bleeder in the bathroom, along with raising and lowering the trailer. And today I parked the trailer on a hill for 3 minutes, opened the bleeder, and did the same sloping down - in all of these cases I have fluid coming out. The glycol is moving up and down in the reservoir, once it overflowed. I am only getting heat the first 2 to 3 feet in the hose towards the bathroom - which leads me to think I have an air lock? Tonight, based on the British Alde manual I also turned the circulation pump up to 5 for ten minutes, and got the same results.

To add more confusion to this, in doing the troubleshooting with Nucamp it was determined that while I have the Alde Flow in my trailer it does not come up as an installed accessory. NuCamp sent me a new controller, but when I plugged it in, the Alde Flow still did not show up. With more troubleshooting, I determined tonight that the wire going to the optional board was not plugged in I am assuming when it was manufactured. However after plugging it in, and setting it back to the default settings it still does not show the Alde Flow. 

I don't know if these two issues are related or not. I am also wondering if I have an air lock between the reservoir, which is in the front left corner and the line that runs along the back of the bed and into the Alde Flow. While I have really appreciated the assistance NuCamp has given me via email, I am hesitant to go back to the dealer since we have not been happy with their service. Any suggestions or thoughts on what else I could try would be appreciated, thanks.

Sharon_is_SAM

When the Alde bleeder assembly was shot, our first symptom was loss of glycol.  Have you tried giving the metal bleeder valve a good wack?  I understand that the valve can get stuck open resulting in loss of fluid.  I agree - it also sounds like you have air in your circulation.  

Denny16

@Davids. This may be kind of obvious, but when you lift you bunk up to see the Alde system, are you seeing the Red Flo tank behind the Alde boiler like this:

Red Flo tank  is at top of photo, above the Alde boiler.

If you have the red tank, you have made the wire connection, then you must activate it on the Alde control panel:
” ACTIVATING ALDE FLOW

To activate the Alde Flow, it must be enabled in the Alde 3020 control panel. From the Main Menu, go to Settings Menu>Installed Accessories Menu, Tick the box for “Alde Flow”. from the Alde Flo manual.
cheers

Davids

Thanks for your responses. I did not try tapping the bleeder since it was new, but will give that a try. Yes I do have the Alde Flow see attached picture, I have also included a picture of where the wire was not connected. The confusing thing is Denny after I plug it in and go to the control panel like you suggested it does not show up as an accessory, see attach pic even if I restart the unit

Sharon_is_SAM

@David, if the wiring is correctly installed to the Alde Flo, I would reset the control panel.  Turn off the Alde control panel first.  Then, open the top of the Alde.  Disconnect the wire in between the 2 green fuse holders.  Leave it out a few minutes, then reconnect.  Restart the Alde and look to see if the Alde Flo was added as an accessory.  

Denny16

Yes, seems like the issue.  Here is the Alde Flow Check list:

TROUBLESHOOTING

No continuous hot water

• Hot Water Boost automatically deactivates after 30 minutes. Activate Hot Water Boost again.

• Check that “Alde Flow” is ticked in Installed Accessories Menu. The tank symbol will appear in the Standby Screen

when Hot Water Boost is activated.

• Bleed the system of air.

• Check that the Alde Flow’s 12 V circulation pump is connected to the options dongle correctly.

• Check that both gas and electric heating are selected and functioning.

• Check that the Alde Flow’s 12 V circulation pump has 12 V power and is functioning.

“Alde Flow” does not appear in Installed Accessories Menu

• Check that the options dongle is connected to the Alde 3020 Compact HE boiler

• Disconect and then reconect the 12 V power supply to the Compact 3020 after connecting the option dongle to

reboot the settings..

Noise from Alde Flow’s 12 V circulation pump

• Bleed the system of air.

There comes no water despite the fact that the tap is open

• Check that the vehicles fresh water pump is on.

• Check that there is no ice plugs in water tank or pipes.

• Check that all draining valves / FrostControl are closed.

• Check that the vehicle’s water pump is functioning and there is a supply of water.

The “Alde Flow” symbol flashes

• The water is in the process of being heated. The symbol changes to being permanently lit when the temperature

cheers

Davids

Sharon thanks, with your suggestion I now have the Alde Flow showing up under installed accessories!!!
Denny, thanks for the list I will work my way through it.

Davids

I have had some more time to work on this and continue to have the same problem, to summarize where I am right now
 - As the Alde temp rises, the hoses near the unit heat up, though no more than a few feet
 - If I turn the unit off, and open the bleeder valve in the bathroom, only glycol comes out
 - At times as the temperature rises, the fluid in the reservoir builds up and will overflow through the bypass  onto the pavement, sometimes resulting in the fluid being below the min line, so I add more glycol
- Based on feel, both circulation pumps on the Alde and Flow appear to be working
- Raising the trailer up high and low does not seem to help, and running both pumps at the five levels does not seem to help either.
- Even with the mixing value set to its max, the water is warm, but not hot.

A few questions
- Any other suggestions?
- What is the normal running temperature of Alde glycol? Does it maintain a constant temp or fluctuate?
- I understand that it could also be a kinked line. My thinking is that a kinked line would normally occur during manufacturing. Has anyone experienced a kinked line after the system worked fine?
Thanks for your time

Sharon_is_SAM

Do you have the 2 kw electric and gas turned on?  Check this and see if the water temperature improves.

I believe that both the 3010 and 3020 models have a manual glycol pump setting.  Have you been trying to adjust the pump circulation via the control panel?

Is your glycol pump in the Therm mode or Continuous?

The water temperature gets up to 150-160 degrees.  I imagine the glycol temp is similar.  

I read the Flo water temperature Is 104.

N7SHG_Ham

What valve are you opening in the bathroom?

The glycol and water temperature at the Alde itself can be read in the service mode on the control panel. Normal is around 140f and after boost mode for 30 minutes around 180f

It sounds like the glycol is NOT circulating for some reason?

Davids

Sorry for the delay in getting back to you.
I have only been running the gas, since I only have 15amp. I am getting gylcol temperatures around 180, and 160.
The valve I am opening in the bathroom is the bleeder valve for the Alde.
Two other questions
- Does anyone know which way the fluid flows - does it go from the Alde to the bathroom, front of the trailer - clockwise?
- While I feel the heat on the Alde, I do not feel any heat from the Alde Flow
Thanks

Sharon_is_SAM

@Davids how are you adjusting the glycol pump?

Davids

Hi Sharon, I am adjusting the dial on the two circulating pumps, moving them up to 5, when they were are about 2.5
And on the Alde control unit I have it set to continuous

Sharon_is_SAM

Set the pump to Therm.  This has been a problem with a number of Alde issues this season.

Davids

Ok I will give that a try, thanks

Denny16

@Davids, on the Tab400, the circulation is from the Alde to the Flo, then to the rear heater core, and around to the passenger side behind the galley unit.  Next it goes to the front heater core under the dinette front and next to the Washroom the back to the Alde heater return.  There is a check vale between the Flo output and the rear heater core, to maintain the circulation in one direction.

The bleeder valve is at the end of the circulation, before the connection to the Alde return.  

When bleeding to prevent air being sucked back in, you should attach a tube to the bleed valve out and put the other end in a galls container, with some fluid in the container to keep the end of the tube submerged.  Then open the bleed valve and when air bubbles stop, close the valve.  You should be good to go.

That said, this may take several goes to get all the air out, keep an eye on the reservoir level, adding more fluid as needed.  The bleed valve glass container will collect the fluid as it is drained, so you can add it back in after letting it stand for a bit to release any air from it.  There is also an auto bleed valve between the Alde and Flo tanks.
cheers

Davids

Denny thanks for this is very helpful. When I run the system I have heat in the hose coming out of the Alde and you can feel the heat along the hose a foot or two towards the bathroom, the heat also goes back to the circulating pump closest to the alde flow, but not beyond. So I must have a block in the Alde Flow, in the rear or the passenger side,  which would make sense since I had to replace the auto bleed value you mention. 
I will try your suggestion with the hose tomorrow. Thanks 

Denny16

@Davids,  If you have heat in the line in the bathroom/washroom, then heated fluid is circulating out of the Flo.  If the bathroom line was cold, and no head coming from the rear heater core, than the Flo or the Check Valve could be an issue, but does not seem so, if you can bleed and add more fluid.

Cheers

Davids

Denny16 just to clarify my earlier comment, I only feel the heat in the line going to the bathroom, it does not reach the bathroom. If the Flo or Check Valve is the problem, does it make sense that when the Alde heats up it pushes fluid backwards to the reservoir which often overflows when I am trying to bleed the line? Could a bad air lock also do this? I have tried to bleed the lines multiple times, it seems I get very little or no air bleeding out of the bleeder in the bathroom, but often the reservoir overflows, and then I add more fluid?

Sharon_is_SAM

@Davids - if the glycol can not move forward, I assume that the action of the pump increases pressure in the glycol line and that pressure causes the backflow into the expansion tank.  Although unlikely, any possibility that when you replaced the bleeder valve that it went in backwards?  Your system was working before you replaced that valve, so it is either the valve or an airlock.

Davids

@Sharon_is_SAM - I believe I installed the auto bleeder correctly, see attached picture. I am going to pick up a piece of hose that @Denny16 recommended this afternoon. For trying to get the air out, I check that they reservoir has enough fluid, have the two circulating pumps set at five, open the bleeder in the bathroom, and then turn the Alde on for about 10 mins when the temperatures get up to around 180, turn off the Alde and open the bleeder. I have also been raising and lowering the trailer in between trying to encourage air out of the system. Is this correct? Should I be doing anything else? Thanks again. 

Sharon_is_SAM

Note that you should not have the glycol pump running If a bleeder valve is opened as air can be entrained.

I know this is frustrating, but that’s all I have.  Is the air bleeder in your first picture stuck open causing air to entrain?  Just thinking out loud here.

Sharon_is_SAM

Did you see this video?  https://youtu.be/2olLi_O8xXI

If nothing else works, I wonder if you should just drain the unit and start over?

Davids

@Sharon_is_SAM thanks that is the process I have been using. I do turn the pump off when bleeding. When I move the air bleeder I can hear it move so I am thinking it is working. Draining and starting over is something to consider.

Bayliss

@Davids, in the event you have not seen it, or read through it, the link below is to a long and varied discussion on changing the glycol fluid.  No guarantees, but maybe there will be some helpful info in there for you:

https://tab-rv.vanillacommunity.com/discussion/2665/changing-out-the-alde-fluid/p1

Also, just a thought . . . . . . . you indicated that you raised the pump setting to "5" for about 10 minutes.  After that, did you return it back to 1.5 to 2 (normal setting range)?  I've never read anything about it, but if you did not return the pump to its prior setting, I wonder if there is too much pressure being created in the line due to the high pump setting.

Davids

Thanks for the link I will have a look at it

Denny16

@Davids. Found out the Alde Circulation from the Galley unit to the front is via an aluminum pipe inside the bottom of the screen door frame, which gets the glycol fluid from the galley to the front radiator, Nd the return is under the shower pan to to washroom radiator, and back to the Alde heater.  Here is a photo of the tube across the bottom of the door:

The silver Alde glycol tube in front of the door, is covered by the screen door frame, along with the 120VAC cable.  If you remove the screen door frame, be careful not to pinch this wire when reinstalling the frame.
cheers

Tundra57

@Davids where is that air bleed unit you show? I have not seen one in my 2019 tab 400. I added a manual bleedvalve to my system under the 3 way fridge. I added radiators under the tab so i needed to bleed the system.

Denny16

@Tundra57, the manual bleed valve is on top of the washroom Alde heater, behind the panel under the shower unit.  You need to pull,the top,of the cover away from the bulkhead and you should see the valve.  This is the highest point in the circulation system (along with the expansion tank ) which is where you want to bleed air from, as you are drawing fluid up from the expansion tank pushing the air out as it goes up the washroom heater core.
cheers

Tundra57

Great. Thanks.

lisadbricker

Hi @Davids. We are having a similar issue with our heat not working beyond the Alde storage compartment in the back of our T@B 400. In a different thread we’ve been troubleshooting with helpful advice from others, but nothing has worked. I’m wondering if you solved your issue, and if so, what worked for you?