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Topic: Aquahot mystery start up (Read 715 times) previous topic - next topic

Aquahot mystery start up

Couple of weeks ago, turned on the Aquahot switch under sink;  stayed on for 15 seconds or so then went out;  repeated, same result;  the motor was running blowing cold air from the exhaust.  Left it as is while I was working on the faulty house batteries for a week or so and finally replaced them. 

 Back to the aquahot; tried the switch again and it fired up and surprised it worked as it should.  What happened while it rested for a week or so; how would it repair itself?
Fiddler
1959 Parris Island grad
40' 2001 U320 Build 5875
1999 Suburban K1500 toad
1986 Corvette Pacecar
ssoftail@comcast.net

Re: Aquahot mystery start up

Reply #1 –
Just a WAG but you may have had so low of voltage/amps with a bad battery bank that the fuel shut off valve wouldn't open or the ignitor wouldn't fire.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Aquahot mystery start up

Reply #2 –
I don't have a solution for you, but our's is doing the same thing right now.  Turn Aquahot diesel switch on... stays on for 5 seconds and shuts off.  Hoping ours self-repairs too.  HA...
Russell
'99 U320 CAI 40ft w/Xtreme Full Body Paint
Baton Rouge

The selected media item is not currently available."Tetons"

Re: Aquahot mystery start up

Reply #3 –
If your Aqua Hot is wonky, and you want to talk to the World Renown Black Belt Senior Master AH Technician, just drop Rudy Leggett a PM.

You will never talk to a nicer, friendlier, more knowledgeable individual.  He da Man!

http://www.foreforums.com/index.php?action=profile;u=482
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Aquahot mystery start up

Reply #4 –
Fiddler,

Low voltage from house bank can result in a signal from the flame sensor low enough to prevent firing.  So there is hope you are good to go.  Always run the burner once per month year round, always.

Russell,

My memory of your coach is it is plugged in much of the time keeping the house batts fully charged.  So, my low info, long distance guess is you need burner service.  Once serviced, run once per month.

Chuck,

Hope I do not need to send you a check for these very kind comments, thanks.

As a general note, once the spray pattern of the nozzle is compromised or a burner component fails resulting in the burner failing to fire and faulting, there is almost never healing and a return to normal operation.

Hope this helps.
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 mystery start up

Reply #5 –
I experienced intermittent starting problems with the diesel side for several years. Sometimes cycling the diesel switch would make it start again and sometimes it would start when the thermostat called for heat. This problem continued despite new nozzles and filters, a new controller, and sending the burner to Roger Berke for testing (it never failed while he had it). After several more months, it finally would never start. A new igniter coil solved the problem and it has worked flawlessly for several years.  A new igniter is pricey!

Re: Aquahot mystery start up

Reply #6 –
Here is my approach for those that have an intermitant firing issue.  You might consider coming to Baytown, TX, for a week or so.  I agree with Bob, the burner is going to run fine while I am at the coach.

The first thing I guess for intermittant firing is the coil.  So I will replace it and let you run the burner however many days you have found to be when the burner faults again.  If you call and share it has faulted again, I will re-install your coil and guess the control unit.  Normally those two guesses fix it.  But if you were to call and it faulted again, I would re-install your control unit and continue guessing.

The right guess is found by being persistant in searching for the bad part.  Once found, you would be charged for the part and time to replace.  No charge for the parts that did not fix the issue because they are no longer installed in your heater.  Will not take to long as most parts do not fail intermittantly, they fail and stay failed.

I have done this many times.  You do need to be here till the problem is solved.  Plus, Houston is a big area.  So being here is Baytown.  Many RV Parks in Houston area are over an hour each way which is to many travel hours running back and forth till the right part is found.  Staying in Baytown helps me help you.

All the best.
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 mystery start up

Reply #7 –
A new coil solved this exact problem for me. It is really hard to test the coil, so I replaced it.
Good luck.
Rick & Deborah Webster
2002 3610 U320 #5964
2014 Jeep Wrangler Sahara JKU- 'Copperhead'
Richland Chambers Lake, East Texas

Re: Aquahot mystery start up

Reply #8 –
Rick,

The test for the coil is to fire or make it arc the points 100 times.  If it fails to fire even one time in the 100 tries, replace.  But every intemittant coil I have replaced successfully passed this test.

So, I do agree it is hard to test the coil for sure.  This why my first guess is the coil.
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 mystery start up

Reply #9 –
Oh my coil is one expensive part to replace. Was going to order one after reading this to have it on hand but now second guessing it. But will probably still get one anyway. Rudy what is the failure rate on this part? Is it worth having it as a spare or just wait till something happens....  Aqua hot service manual

Bob
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Aquahot mystery start up

Reply #10 –
Quote from: Bob and Julie –
Oh my coil is one expensive part to replace. Was going to order one after reading this to have it on hand but now second guessing it. But will probably still get one anyway. Rudy what is the failure rate on this part? Is it worth having it as a spare or just wait till something happens....
Bob
Bob, it is the one thing I am now going to buy as a spare to carry. Even though the failure rate is very low if it quits on one of my trips I would be without hot water and heat while the new one showed up. This will complete the most failed items on the AH. I have a spare controller, flame sensor and nozzles on the coach now.
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 mystery start up

Reply #11 –
Bob,

Just got home from a heater repair.  I agree that coil failure is not often but if failed, no fire till replaced.

Do remember, one can be over nighted to you for a price.  So hard to say you really need to carry one but I can say you will rarely need a spare.
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 mystery start up

Reply #12 –
What Chuck said in reply #3 X 10. They don't get no better.

Larry
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318