BAC Forum
General Boards => Technical Support => Topic started by: Steve Misemer on June 13, 2022, 10:14:16 PM
-
Hi all,
As you can see from my topic I am having difficulty with my aquahot for hot water and the furnace.
Yesterday we had hot water and the furnace working no problem. I did see that both the electric and diesel buttons were lit-up. Eventually the diesel one went off.
Now today we do not have any hot water even though the Aquahot electric button is on. I have tried to turn on the diesel Aquahot via the push button and the light will go on for a few seconds then shut off.
I have checked for any faults on the electronic control panel and nothing shows.
I checked the shore power and interior breakers.
I'm at a loss.
We are in Yellowstone and the temp supposed to get down to the mid 20's tonight and tomorrow. Kinda want to figure this out asap.
Any ideas.
Thank you
Steve
-
Steve,
What is the Model number for your aqua hot and do you have the owner's manual? Fred
-
AHE-100-04
Reviewing the manual.
We can hear some noise like it trying. And when I go to the aqua hot exhaust it's just blowing clod air. No heat then after a minute or so no air comes out
-
Do you have any portable electric heaters on board? Things are not going to freeze if in the mid 20s for one night. When was the diesel nozzle cleaned last? and the fuel filter for the Wabasto unit. It also sounds like the 120 volt thermostat safety limit switch may need to be reset. Do you have the owners and service manual? You can go to "Coach Assist" and then scroll down to Heating & AC then select Aqua hot to open available manuals. After downloading AHE-100-04 it has a great trouble shooting guide. Fred
-
Steve, is your expansion tank fluid level showing anything?
-
I looked hoping this would fix my issue . But the fluid levels checked out ok.
-
Do you have any portable electric heaters on board? Things are not going to freeze if in the mid 20s for one night. When was the diesel nozzle cleaned last? and the fuel filter for the Wabasto unit. It also sounds like the 120 volt thermostat safety limit switch may need to be reset. Do you have the owners and service manual? You can go to "Coach Assist" and then scroll down to Heating & AC then select Aqua hot to open available manuals. After downloading AHE-100-04 it has a great trouble shooting guide. Fred
Fred thank you. I went through the manual and did as much as I could with the tools I have on me. We can't even get the electric side of the aquahot tonwork.
-
Steve,
Just checking since I didn't see you mentioning it; Did you press the Reset button on the control panel of the AH?
Steve
-
Sure did.
The only thing that showed up and we couldn't clear " low temp vutoff status" but the manual said this wasn't used in my model of aquahot.
The aquahot electric light stays on in the coach. But it's not working
-
Steve,
Suggest you give Roger Berke a call at http://www.rvhydronicheaterrepair.com/
He's an expert on these units and very helpful. I'll take another look at your symptoms when time permits also.
Steve
-
Steve, try to by pass your float switch simply by disconnecting the the two wires that protrude from the back of the switch and run a jumper wire between the 2 wires that were connected to the switch. You must insure that your fluid level is maintained.
-
Also, did you try the 2 resets that Fred mentioned. Location not obvious, but behind the cover shown in attached.
-
I recently had a similar issue and finally figured out it was a faulty optical flame sensor in the burner. The unit would try to fire but when the controller board could not detect a "Flame on" signal from the optical sensor it would shut down the diesel burner. I replaced the sensor and the nozzle at the same time and all was fine. The system will continue to cycle , blowing cold air for a minute or three after it shuts down .The electrical should eventually heat the fluid but when you are running the furnace the electrical element just can't keep up.
Hope this helps.
Dwight
-
Steve,
Your stated symptoms indicate the system is detecting a low fluid condition. Paragraph 4.5 in the AHE-100-04 service manual states that the Low Temp Cutoff Error lamp will illuminate when a low antifreeze / water condition is detected. Neither diesel or electric will function when this condition exists. Since you indicated the tank level was OK I'd focus on the float switch and jumper it per Byran's suggestion to verify that the system functions. See pg 17 of the service manual for float switch troubleshooting.
IMHO focus on getting the electric portion of the system working as it is much simpler with fewer components than the diesel portion and I suspect you have a single issue that is preventing both systems from working.
Steve
-
Steve,
I believe Steve is giving some solid guidance. It is really to jump wire 15 & 16 using a paper clip to prove the issue. It is not a fix just a confirmation that the issue is a defective float switch or low coolant. Fred
-
Referencing Steve’s and Bryan’s comments above, last year I had to replace my float switch. Like they indicated, my jumpering those contacts on the control panel/board was as easy as it gets to do, and the unit fired right up. That bypass of the float switch can keep you in hot water (pun unintended) and floor heat until repairs can be made. Just keep an eye on the expansion tank in case it gets low.
Joel
-
Thanks Fred, that saves me posting a similar guidance image I’d started configuring. 👍🏻
-
Steve
A physical check of the antifreeze level should be done at the radiator cap on the Aquahot to make absolutely certain that the boiler has enough antifreeze in it as a bad pressure cap could allow the boiler level to go down without lowering the expansion tank.( Aquahot recommends periodically replacement of the rad cap ).
The burner combustion chamber will be damaged ( cracked ) if the diesel burn is run without enough boiler antifreeze to allow it to transfer heat and keep the combustion chamber from over heating this is why the float switch is installed to prevent the damage caused by running the system with low boiler fluid.
Be absolutely sure the boiler is full if you bypass the float switch
Hope this helps
Eric
-
Thank you everyone for the replies. Unfortunately I injured my right arm ( I think I strained or pulled some tendons) while in Yellowstone (I was trying to help a neighboring camper evacuate quickly) and I won't be able to do any additional troubleshooting this trip. I was able to left hand to our next stop. Where I'm going to rest my arm and shoulder and head back to home asap.
I'll take the coach to our service shop and have them inspect and remedy the situation.
-
Steve,
Sorry to hear about your difficulties on your recent trip. Unfortunately the Aqua Hot safety switches can fail at any time. A service of the nozzle and fuel filters most likely would not have prevented a safety switch from failing. Just one of those things that happens when operating these technical machines. Hope you get to feeling better and your next outing is more enjoyable. Hang in there!
-
I think Frank said it, Steve. The float switch, if that's what's wrong, is not something a normal hydroponics service would be expected to check. For one thing they'd have to at least partially drain the internal tank to remove the switch for examination, and even then it may not reveal a hidden weakness. Units of our era used a switch with a plastic arm that is what failed on mine. The replacement for it today is a stronger model.
And I have to add that replacing the switch would be a relatively easy task except for the need of a special socket because the switch's wires are in the way of a normal socket. In my case I bought a super-deep socket so the wires would fit up inside it, out of the way of the socket fitting down over the bolt head. Even then it took a lot of finesse, trial and error, and a little advice from the fellows here. See the two yellow wires coming out of the switch in its pocket in the foil insulation? The spade connectors seen below them unclip easily, but then those few inches of double wires and two spade connectors have to be stuffed into a socket wrench socket. Or you have to cut special slots in the side of a socket to run the wires through. Yeah, you can just clip the wires off at the switch to readily remove the old one; but then you're going to have to put the new switch in without damaging its wires.
You may not be able to save the drained fluid without contaminating it in the process, due to the confined area you have to work in. New fluid would be advisable, but be sure you mix it correctly. And be sure you use the Camco Boiler fluid designed for hydronics. You may want to get a fluid refractometer to test the old fluid remaining and mix the new correctly. The device is handy for other fluid tests also, like battery acid and antifreeze. Then its always fun trying to pour fluid back into the filler neck with such limited access!
i.e. - You may find it best to have an experienced hydroponics technician do the job, rather than pull another muscle trying to maneuver in there.
That all said, as noted here previously, the tank's filler neck has been an issue for others here. Apparently the extension that holds the overflow tube or the weld to the tank can weaken and fail, causing fluid loss through leakage and loss of proper pressure. While I had mine off to fish for the broken off switch part (forget doing that, it doesn't hurt anything floating around in there and even if you spot it you'll never fish it out), I examined the filler neck and hose for bad areas, but it all looked good.
Joel
For reference if needed: John Carillo may be the best source, as it was for me.
https://www.heatmyrv.com/product/float-switch-brass-ele-800-002/
-
I wanted to update this post.
Had the coach in for service to look into the Aquahot. Here is what they found
Jumper was installed to bypass the low fluid cutoff.
Aquahot was very low on fluid.
Radiator cap was bad.
Radiator cap neck was damaged and bent and wouldn't let overflow tank work or show fluid level.
Aquahot control board had alot of corrosion on it. And alotbof the diodes looked burnt or damaged.
All of the above items replaced and or repaired. Works great now.
I wanted to post a picture of the board but I couldn't figure out how to convert a 4Mb picture to 300kbs.
Is there a way to protect these boards for the elements?
Thank you
Steve
-
Steve,
To resize photos see the guide on the Forum Assistance board.
Steve
-
Steve M,
If I understand your latest updated post, you stated that there was a "jumper already installed to by-pass the float switch"? If that was the case, that TEMPORARY jumper wire could have caused a lot of the damage. The jumper wire is for trouble-shooting purposes only and when used it by-passes the safety system. If the unit was allowed to operate with insufficient coolant inside, all sorts of damage can occur. Please advise. Fred
-
Yes the tech said that there was a "jumper" installed. I did not install one. The good news is that everything checked out ok by the tech afterwards and seems the be working fine during our current 4th of July trip.
-
That bay should be relatively resistant to moisture intrusion, Steve. Perhaps the failed filler/cap neck resulted in some fluid presence where it shouldn’t be, but the vapor point and pH of that I’d not think a corrosion threat, but maybe so. Be certain that servicing techs cleaned up any spilled fluid in that compartment. Check that the bay door seals properly when closed. The Hydronics unit gets warm and can vaporize fluids or water present in the bay proper., so it can get to the control boards.
There is a product called Corrosion-X that can be used on basic electrical connectors and buss’, but I’m not sure I’d use it on circuit boards because it’s protective residue might be problematic for future repairs and tests. Even in our formerly leaking front electrical bay that was often flooded, circuit boards didn’t corrode but barrel connectors, screws, and fasteners did. The circuit board in our HydroHot bay has been clean and dry for 16 years.
Another protective product I use on finer connections and circuit board repairs is “Deoxit”. It comes in various forms for certain uses, but for just protective care not requiring pre-cleaning I’d use Deoxit Shield. Spray cans, bottles, and pens aren’t cheap, for sure, but a little can go far if sparingly used; which is why I prefer the brush in a bottle version so I can delicately just dab at only metals and solder points.
https://caig.com/deoxit-shield-s-series/
Check for sales online, and be aware that the micro-brush bottle is quite a bit tinier than its photo reveals. Too small for me.
Joel
-
Joel
Thank you