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Topic: Aqua Hot issue (Read 1232 times) previous topic - next topic

Aqua Hot issue

Be prepared to be shocked! :whistle:  I had a strange Aqua Hot issue last night. We were out late due to our pet having to go to an emergency vet clinic. Got home at 1:30am and I noticed that the diesel light was out.

While parked and on the utility pole. We leave the diesel and electric switches on. So I turned off both switches for a few minutes, Then turned on the diesel. the light didn't come on after the delay. Turned diesel switch off again for a while. Then it lit up and the burner fired up. I left the electric off to force the diesel side to provide heat. It went through a full cycle and shut down. So off to bed. Woke up later to a cold coach. Diesel light was out again. Went through the same procedure of switching the diesel off for a while and it came back on and has been working since. And it had been working perfectly prior.

So I just don't get it. Our fuel tank was filled just ten miles before parking. A new control box was installed a few months ago. The AH is serviced every year by an authorized service tech. This year it was serviced by Oregon Motor Coach. The whole Aqua Hot system was pulled and sent to the factory and rebuilt 4 years ago.

So, does the Foretravel think tank have any idea what might be up?

Re: Aqua Hot issue

Reply #1 –
Which control box was installed? That is the symptom of a failing one.  Can be the flame sensor or the igniter also. Call Rudy.

Re: Aqua Hot issue

Reply #2 –
Quote from: craneman –
Which control box was installed? That is the symptom of a failing one.  Can be the flame sensor or the igniter also. Call Rudy.
It is the latest and greatest control box. Not the silver or Spiros box.

Re: Aqua Hot issue

Reply #3 –
I'd rule out the control box then.

Re: Aqua Hot issue

Reply #5 –
Mine was doing the same thing. Took it in and had it serviced again. The service man said it was the dirtiest one he'd ever seen. Funny because it had been serviced only 8 months earlier.  Also the diodes in the wiring had been replaced with regular wire causing feed back issues. The shop cleaned it up and replaced nozzle & filter and the diodes. Works fine now, wasn't the control box. FOT did the service last time before I bought the coach but did not replace the exhaust that was bad-full of soot and rust. So you might want to just service the unit again and check your exhaust.

Re: Aqua Hot issue

Reply #6 –
Quote from: turbojack –

Never say never.  I can not tell you how many times I have gone on a service call and I am told.  "It can't be xx, it is brand new."
How true. However, As it's a factory part bought from Rudy. I suppose it would (or at least should) have a teeny tiny bit of a warranty. But then this is Aqua Hot and they barely warrant their work on rebuilds.

Re: Aqua Hot issue

Reply #7 –
So far today. The AH has been on diesel only and has come on once (it is 65 in Tucson right now) and it works as it should.
We sure love the Aqua Hot when it works. But it seems to like not working more than working properly.  Of all the individual systems on our coach. It has been the biggest money pit.

But as the AH has decided to work now. We are good with that and will keep an eye on it.

Re: Aqua Hot issue

Reply #8 –
I'm sorry about your pet and hope it is ok. I'm not sure why this kind of crap always happens at the worst possible times.

Re: Aqua Hot issue

Reply #9 –
Quote from: Elliott –
I'm sorry about your pet and hope it is ok. I'm not sure why this kind of crap always happens at the worst possible times.
It's the fault of some bloke named Murphy. Our new Cat was coughing and having trouble breathing. Vet said it might have Asthma. We are awaiting lab results.

Re: Aqua Hot issue

Reply #10 –
Did you reach out to Rudy and ask him?  Better than guessing.

Re: Aqua Hot issue

Reply #12 –
I chased the exact same symptoms for nearly 3 years. Would work great for months and then  would start erratically for months. Had the burner overhauled no change. Finally it failed and would not restart with multiple attempts. Turned out it was the igniter.

Re: Aqua Hot issue

Reply #13 –
Rudy has a magic box that tests most if not all of the burner functions. I think he said if the igniter fails 1 time in a 100 tries to replace it.
Here's a quick question does the igniter fire just to ignite the fuel stream or does it fire continuously while the burner is running?

Re: Aqua Hot issue

Reply #14 –
I had the same experience as Bob. The igniter failed sporadically. It's easy to fix something that stays broke, not so easy if it only fails once in a while. The igniter coil is crazy expensive, not something you change unless it fails. Mine finally quit, think it was about $450 and it was worth it to have an Aquahot that fires reliably.

Re: Aqua Hot issue

Reply #15 –
I had an intermittent igniter go too.

Re: Aqua Hot issue

Reply #16 –
Quote from: folivier –
Rudy has a magic box that tests most if not all of the burner functions. I think he said if the igniter fails 1 time in a 100 tries to replace it.
Here's a quick question does the igniter fire just to ignite the fuel stream or does it fire continuously while the burner is running?
I believe the flame sensor shuts off the igniter but will wait for Rudy.

Re: Aqua Hot issue

Reply #17 –
Two things,

One: The Ignitor coil fires till the fame sensor reports a fire.  Once a fire is established the coil is de-energized.

Two:  The two items that can be intermmitant are the Control Unit (brain box on the burner) and the Ignitor Coil.

A test of the coil it to fire it 100 times.  If it fails and of the 100 tries, replace.  But, I have many pass this test but fail to fire the burner during the night.  So, this test is not absolute.

The way I fix intemmitant firing is to replace the control unit first.  It is just un-plug and re-plug.  If the intermmitant firing goes away in a few days, done.  But if it continues, remove new control unit and replace the coil.  More work here but that generally makes the intemmitant firing stop and problem solved.

This takes several days to solve but the owner only purchases the part that solved the problem.

Re: Aqua Hot issue

Reply #18 –
We all have a love hate relationship with our Aqua Hot's!  In the last year and a half, we have replaced the coil, the control box to the latest and greatest, thanks Rudy and the AH was serviced.  Most money we have spent on either of the Foretravel's we have owned.  Heading next week to see Rudy for a service and another issue with AH!

Re: Aqua Hot issue

Reply #19 –
Per Rudy, looks like it will need a coil R&R.