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Topic: Aqua Hot issue (Read 583 times) previous topic - next topic

Aqua Hot issue

While camping in Oregon a few weeks ago. I turned on the AH and the blower started but took almost a minute to actually ignite and then smoked for a bit. Then it operated as normal.
On the trip to Idaho this week. It was acting up again. But with seemingly random issues. Such as before where the blower was on, But this time it never did fire up and the blower just kept running. After running and no fire for 10-15 minutes. I turned the diesel switch off, Waited for a bit and tried again and it fired up. Another time it would fire up normally but keep running after the fire went out. Yet another time. Turning the diesel switch on did nothing. It made for two pretty cold nights when the temps got down to the 40's while we were dry camping.

I do have an appointment with a qualified Aqua Hot shop on Monday. But I would still like some guidance so I have a bit of knowledge of what part of the AH they should be looking at and also to not take advantage of me. My Aqua Hot was rebuilt 3 years ago and I have had the annual maint performed while in Tucson every winter.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Aqua Hot issue

Reply #1 –
Sounds like perhaps the flame sensor is not working well or the control unit is acting up.

The flame sensor can be checked for resistance in the dark, should be many many meg ohms or even open circuit.  Then in bright light should be less than 200 ohms, the lower number the better.

If flame sensor passes, the the control unit jumps to the most likely culprit especially if it is a black Sperios box.  I just put the offending part on and test the result to make sure I have diagnosed correctly.  Sometimes I err and have to remove the first part and install the one that results in a fix.

Your service center is welcome to call me to consult should they wish to.  But most of the time it is not rocket science and can be sorted out just fine.  All the best.

Rudy  7 one 3  8 one 8    3234
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aqua Hot issue

Reply #2 –
Rudy is the man!
Joe & Dottie Allen
Sold!  December 2023.      2000 U320; build # 5645
Our coach " Maxine"
Motorcade #  15922;  Escapee 150950; FMCA F330833; Boondockers Welcome;  Harvest Hosts;  Thousand Trails
'98 U320 from 2000-'06
USAF '62-'66

"Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for." ―Epicurus

Re: Aqua Hot issue

Reply #3 –
Gee Rudy, I hope it's not another brain box. I installed a rebuilt silver box just 18 months ago.
But as we know all to well. Electronics can be very fickle or run trouble free for many decades. If it needs a brain box. (mine is the silver one) I'll order one from you.

Thanks for the advice Rudy

Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Aqua Hot issue

Reply #4 –
If it is the silver box, get the solid state one from Rudy. I did. Been good, so far.
Glenn and Amy Beinfest
2001 36' U320
#5812
2014 Honda CRV

No Whining on the YACHT

Re: Aqua Hot issue

Reply #5 –
Quote from: GleamB –
If it is the silver box, get the solid state one from Rudy. I did. Been good, so far.
Is this a new thing?  I got a replacement silver box from Rudy 18 months ago. So not sure if that falls into the solid state edition.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Aqua Hot issue

Reply #6 –
The silver box was used for years.  Then, Webasto switched to the troublesome Sperios box.  Aqua Hot reacted by designing and manufacturing the new solid state control unit.

The rebuilt silver box is a good alternative to the solid state box.  But manual relays will be a step behind the solid state box.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aqua Hot issue

Reply #7 –
I keep my old, rebuilt, silver box as a backup.....just in case. I had replaced this unit TWICE in less than three years. When Rudy told me about the solid state unit, I didn't hesitate.
Glenn and Amy Beinfest
2001 36' U320
#5812
2014 Honda CRV

No Whining on the YACHT

Re: Aqua Hot issue

Reply #8 –
Quote from: GleamB –
I keep my old, rebuilt, silver box as a backup.....just in case. I had replaced this unit TWICE in less than three years. When Rudy told me about the solid state unit, I didn't hesitate.
If the brain box is brain dead. I'll go with the solid state.
 
So Rudy, Do you sell the solid state box and do you then buy the old silver box to keep the species vital? I would of course prefer to support your business if I can.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Aqua Hot issue

Reply #9 –
Quote from: bigdog –
If the brain box is brain dead. I'll go with the solid state.
 
So Rudy, Do you sell the solid state box and do you then buy the old silver box to keep the species vital? I would of course prefer to support your business if I can.
Yes Rudy has them, the plugs On the solid state box are on wires instead of being mounted on the side of the box. I think there is a core charge if you don't return the broke silver box.


Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.