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Topic: Aquahot burner rebuild (Read 1099 times) previous topic - next topic

Aquahot burner rebuild

I admit to delaying aqua Hot yearly service as I was using it and it seemed to be working perfectly. Recently though I got a feeling that it was time to change the nozzle and I did but I didn't clean the combustion chamber out. A few days later I had to have surgery and left the coach with everything off and of course the temperature in Oklahoma City decided to get around freezing. Came back to the coach turned both the electric and the diesel element on made sure things were working and left. 2 Days after I returned, I woke up to a cold coach. For the first time ever the aquahot had shut itself off.
Once it warmed up above 40 I pulled everything apart remove the burner and immediately notice that there was a ton of carbon coming out big chunks of it. Had a hard time getting the combustion chamber out but once I did it too was full of carbon deposits. Almost as if somebody had shoved the paperback book in there and let it burn. Immediately I thought to the thread somebody recently put about delayed maintenance and started to berate myself but realize that that was not going to help and moved on.
After cleaning everything up I did notice that all of the grommets were dry and hard and all of the wires inside were very hard and difficult to bend. One of the wires going to the fuel solenoid had lost insulation the plugs were so brittle the plastic was falling off as I tried to remove it. After cleaning everything up I put it back together fired it up and it wouldn't ignite.
I had a feeling I had reversed the fuel lines. A quick call to Rudy to confirm that and thanks for that info Rudy, and then with the fuel lines and the correct position, fired it up. Nothing happened except the pump ran but I shut it off waited 15 minutes restarted and now it fired up with a huge cloud of black smoke and black sooty particles which I expected. I vacuumed out a large amount of stuff from the combustion chamber but I knew there would be more in there. I let it run for a while but the black smoke never stopped. A maintenance guy from the RV park I'm at was thinking the coach was on fire and ran over and banged on the side while I was in the shower getting the smell of diesel fuel off of me. Another story for the fire ring.
Another call to Rudy and parts are ordered I plan on rebuilding the blower with new clutch and bearings as well as a new wire harness. Another clean out of course once I get the parts will be in the order and I'm going to pay particular attention to the exhaust. Also going to open up the inlet opening further. I've been at high elevation most of the summer and I'm sure the thing was burning lean. I'll post further pictures of course once I get the parts in.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #1 –
My guess is that when you did the nozzle you didn't get the burner sealed all the way around. That would have kept the burner from getting enough air. I made that mistake one time but checked for air leaks around the burner with my hand and felt air pressure behind the burner. backed the j bolts back off and re-tightened more carefully to balance and no air leak. Also if at high altitudes it will run rich not lean.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aquahot burner rebuild

Reply #2 –
I agree with craneman. In looking at picture soot on nozzle and behind on plate
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Aquahot burner rebuild

Reply #3 –
Yeah you're right it was burning rich not lean. That's what I meant to say but didn't proofread it. I'm pretty sure it wasn't sealed around the back side as I cut one of my knuckles pretty good trying to get the j bolt on. So I did not check the backside for air leaks.
I also recently broke one of Rudy's rules and had the cover back on it.
Still it could be worse the controller board could be bad or something this is a cheaper and easier fix.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #4 –
Having the cover on could have saved the coach from burning down. When the burner doesn't seal there is a lot of heat and heat rises.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aquahot burner rebuild

Reply #5 –
The fire created by the Webasto burner is contained in the combustion chamber.  There has not been an Aqua Hot caused fire to my knowledge.
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: Aquahot burner rebuild

Reply #6 –
I was commenting on the fact that the combustion chamber is not sealed when the burner is not seated. I know when the burner is seated there is nothing getting past the seal.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aquahot burner rebuild

Reply #7 –
A poorly seated burner will leak combustion air producing black smoke and lots of soot.  The poorly burning fire is still in the combustion chamber.  To get the fire from the nozzle to be out of the chamber, the burner would need to be laying in the pan completely dismounted.

I have found burners loose providing black smoke but never found one loose in the pan.  Much less loose and firing
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: Aquahot burner rebuild

Reply #8 –
Well again Rudy was right, there was a big leak in the back. I can't tell you how much love I have for being able to remove the aquahot blower burner assembly easily. Yeah, not
I feel like I pulled a bonehead move but still don't really understand how I did it. Parts arrived and today was the day so I pulled the blower/burner out and of course had to cut the wires to do so I paid attention and made sure that everywhere I cut had a corresponding wire cut it and then proceeded to tear the unit down. It's a pretty interesting design and I enjoyed doing it couple of frustrations as I know you all understand what I mean when I say that on getting things disassembled but I did and using the parts I put everything back together again. I found that one of the bearings was completely gone and the other one was pretty bad I also found that the wiring harness seriously needed to be replaced which I'm glad I had ordered one and it all seemed pretty straightforward until it's not. Like getting the cover back on it only goes on one way maybe and I'm pretty sure I put it on the wrong way took me about 30 minutes just to figure out how to do that. The fuel solenoid also has some issues I'm probably going to have to remove and replace that at some time, mostly due to heat on the plastic parts. With the new bearings in place everything seemed to work fine so I put it back together again. I had forgotten to Mark which one was the fuel return so when it didn't initially start again I just reverse them. I need to remember to mark that. I have pictures of it but it was from before I changed the fuel lines. Which incidentally after 2 years my fuel lines look like they already need to be replaced from the fuel filter to the unit. A lot of small cracks. Back to the wiring harness. One of the wires coming out of the new harness is black but there's no wire coming out of the aqua Hot to match it. I looked at the old harness it looked like it was combined with an orange wire but I don't know where that goes upstream. So the aqua height ran but wouldn't start. I called my nearest aqua Hot expert AKA Rudy and as usual he was a wealth of information but I didn't understand what he was telling me. I know that if he was in front of me he would know exactly where that wire goes but after working on that since 10:00 a.m. and it was now three or four in the afternoon I was past tired.
Tomorrow it's going to get into the 40s here in Oklahoma while today was almost up to the '80s I would like my aquahot to be working but right now it's not. I'm going to go back in tomorrow after looking at the wiring diagrams and see if I can figure out where that black wire off the new wiring harness is supposed to go.
And i I found that my overflow hose was kaput and I am low on coolant. I purchased a gallon from Amazon... Yeah not enough. I always look at the overflow and it always looks fine didn't realize that it wasn't connected anymore.
Too much time traveling and enjoying my life and not enough working on this coach trying to get back into the maintenance mode.
I think the black wire is spliced off the orange wire but still don't know where it went to there's nothing that I can see that's not connected.
Scratches head...
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #9 –
looking at the wire diagrams I see a black wire that goes to something labeled as a M, not sure what that is. when you try to zoom in it gets blurry. going to pull it apart again and see what I missed. Also having trouble with getting the covers to stay in place around the fuel lines. The old ones were pretty hard, and to chisel them out. 
More transfer fluid ordered....  Need to replace the overflow tubing as well.... fun fun. Just had surgery last week, not really what I want to be doing right now. I really don't want to go to Houston to see Rudy but just may have to...
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #10 –
Quote from: Journey, Roam, Explore –
I really don't want to go to Houston to see Rudy but just may have to...

You might be able to pay Rudy to come and see you
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Aquahot burner rebuild

Reply #11 –
I could maybe but it'll be an extra 600 mi for me going to quartzsite next anyway..
Been watching a couple videos and nothing really seems to help at this point although this guy z Motorsport seems to know a bit about aquahide. I'm watching him do a fuel pump replacement on YouTube right now. It's cold outside and windy and I don't feel like getting underneath there and working on it today. In the meantime I cut some of the insulation off of the old wiring harnesses and I'm puzzled because the black wire seems to go and get connected to a fat red or orange wire inside the harness. That part goes to the blower motor and the coil.
I just can't find any part exterior that it would then connect to with the harness since the harness came with and that you would then strip the wire and push it in and tighten the screw down I forget what it's called..
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #12 –
You should have a printed copy or saved file on your computer of this manual. It has the colors of the wires if you take the time to read it.

https://library.aquahot.com/wp-content/uploads/2022/04/AHE-100-02S-Service-Manual-Rev.-B-9-27-2011.pdf
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aquahot burner rebuild

Reply #13 –
Oh I've read it. Several of them. It still doesn't really tell me what I needed to know. I finally got a hold of the guy that works for the company that made the new wiring harness. The black wire is for an system that had an hour meter. The black wire is not necessary.
He also told me that I probably had the coil hooked up wrong. I thought I had paid attention to what wire was what but evidently black doesn't go to black yellow goes to Black.
I got everything hooked back together again and fired it up and it ran the purge cycle never fired the boiler and then shut off. When I went to go recycle the light would not come on on either the diesel burner switch or the electric elements switch. Both are 10 amp ATO fuses. I replaced the fuses recycled it and now only one fuse blue after its cycled and ran for several minutes but the burner again never came on. I have a problem with the fuel solenoid being kind of quirky and the wires not really wanting to stay on so I may have to check the solenoid as well. He told me if I put a 12 volt battery to the blue and brown wire that that should make the solenoid click. I haven't tested that yet I got tired. I'm going to take my son out to dinner. I'll try to mess with it again tomorrow.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #14 –
Well success! After checking on my wiring and my fuel feed setup, I turned it on let it Purge turned it off waited 15 minutes turned it back on again and it started up with a lot of black smoke which I expected. I let it run for a while the smoke chilled out and now it is running but I am low on transfer fluid and it was supposed to come yesterday and it's delayed so turned it off. Put the electric element on and everything works.
I do have a little issue though with one of the t-bolts. The one closest to the opening is stripped of threads and will not tighten down all the way. Anyone have an idea on the correct way to repair this? I thought about just running a tap over it but there's just not a whole lot of room for that and I'm not really sure how you would get it out but I'm sure somebody knows so putting that out there.
It would have been a lot easier with better access.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #15 –
I believe those bolts are replaceable.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Aquahot burner rebuild

Reply #16 –
Elliot broke one maybe he will chime in on how to change it. I bought 2 spares after his posting.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aquahot burner rebuild

Reply #17 –
I have two coming from John Carrillo. It's a three-piece part with a eyebolt, the nut with the washer built in, and then the pin that goes into the eye. There is a thread on the IRV2 forums that addresses it. I should be able to use just a punch to remove the pin, but I'm afraid that will break the aluminum housing around it so I'm just going to drill it out. I'll use a small bit and go progressively higher until it is able to be removed.
Just finished putting some more fluid in and ran it until it was fully hot and the burner shut off. Still got a little bit of black smoke coming out but very little, I don't feel any leaks around the burner, and other than the bolt I think it's a job done. I had to install a new hose for the overflow and I've got air coming out now as it was priming. I put one gallon into the top and half a gallon into the overflow container. When it was running I saw lots of air coming out of the hose and into the overflow. At some point I'll probably drain the fluid and refill. Maybe at quartzite.
When they replace the basement for the previous owner they had the drain hose coming out of the bottom. They also never put in a fresh air intake.
But I got hot water again and that's all that matters.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot burner rebuild

Reply #18 –
Quote from: Journey, Roam, Explore –
I have two coming from John Carrillo. It's a three-piece part with a eyebolt, the nut with the washer built in, and then the pin that goes into the eye. There is a thread on the IRV2 forums that addresses it. I should be able to use just a punch to remove the pin, but I'm afraid that will break the aluminum housing around it so I'm just going to drill it out. I'll use a small bit and go progressively higher until it is able to be removed.
Just finished putting some more fluid in and ran it until it was fully hot and the burner shut off. Still got a little bit of black smoke coming out but very little, I don't feel any leaks around the burner, and other than the bolt I think it's a job done. I had to install a new hose for the overflow and I've got air coming out now as it was priming. I put one gallon into the top and half a gallon into the overflow container. When it was running I saw lots of air coming out of the hose and into the overflow. At some point I'll probably drain the fluid and refill. Maybe at quartzite.
When they replace the basement for the previous owner they had the drain hose coming out of the bottom. They also never put in a fresh air intake.
But I got hot water again and that's all that matters.

Get a small c-clamp and put a socket on the opposite side larger dia. than the pin and push it out with a small socket against the pin.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean