Aqua Hot Problem

[ERay]

I turned on the AH on the dash this morning and it started... ran for a few minutes and shut down... the light on the dash was on... I went outside and came back in and the light was off but the switch was still on... I turned the switch off and then back on and the light came on but it didnt start... I turned it back off... anyone have an idea... I just had it serviced 6 weeks ago and ran it all the time I was parked in GA.

thanks in advance for any input

[Hisham Amaral]

Eddie

Have you done the annual nozzle and fuel filter change? If these two items are not done you may have that condition. There are many other things that can be wrong but these are the simple things you can do to see if this will fix you issue. You can go on the Aqui Hot web site and down load their service and parts manual if think it is still free.!!!
Please call if you need additional help. Cell 248-935-5390

[ERay]

I just had it serviced at Parliment Coach 6 weeks ago... will check the web site... thanks

Along with nozzle and fuel filter is the flame sensor. There's a photocell near the flame that turns off the fuel if no flame is sensed. The sensor could be dirty or faulty.

[Hisham Amaral]

Eddie

The battery power should be up at or above 12.3 volts. The batteries powers the fan motor and the fuel pump on the Aqui Hot they must fully charged, other issues would be the fues in the Aqui Hot could have bruned out, the fuse is inside by the side of the SS box.

[Roger Berke]

Eddie

This is a portion of a help file that I wrote. It should give you some idea of what is going on.

Question - When I turn the diesel switch on the green light is illuminated. The Aqua-Hot burner makes noise for a couple of minutes but does not ignite. Then green light goes out and unit shuts down after a couple of minutes.


Answer - What you are experiencing is a failure in the start up sequence of the diesel burner.

When you turn on the diesel heat, the diesel burner goes into a lighting sequence. The following things happen in this order.

1. The blower motor starts, which starts the fuel pump.
2. The motor runs for about 10 – 20 seconds to allow fuel pressure to build up and stabilize.
3. The fuel solenoid opens (spraying fuel into the burning chamber), the ignition coil starts creating a spark across the electrodes (igniting the fuel that has been sprayed into the burning chamber).
4. There is a very slight delay. The photocell (that is adjacent to the burning chamber) looks for light from the burning diesel fuel.
5. The photocell inside of the unit will look for flame (light). If it sees light, everything is good and the burner will continue to run.
6. If the photocell DOES NOT see light, the fuel solenoid closes and the `diesel' light next to the switch in your coach goes out. The blower continues to run (purge cycle) for about 2-3 minutes to purge unburned diesel (and heat if the unit has been running).
7. Blower motor shuts down.

As you can see, this is a complicated sequence. If ANY component fails to operate properly, the diesel burner will not operate. This repair and troubleshooting can be difficult. You many need to seek out authorized repair technician. We have some testing equipment that allows us to check out each component involved in the start up sequence separately.

It could be any of the following items that have failed: fuel pump, solenoid valve, ignition coil (+wires + electrodes), or photocell. It could be as simple as a clogged nozzle.

There is excellent troubleshooting information in the Aqua-Hot shop manual for your unit. Here: http://www.aqua-hot.com/b2c/ecom/eco...edManuals.aspx

You should also check to make sure that you have sufficient fuel in your tank. The fuel tank pick up line is like the generator; it will not pick up fuel if the tank is less than ¼ full. I have heard of coaches that won't draw diesel if the tank is less than 1/3 – ½ full. You would know your coach better than anyone else if this is the issue.

There is much more information on the group below.

- Roger Berke -
Moderator - Yahoo Hydronic RV Heating Group
http://autos.groups.yahoo.com/group/HydronicRVHeating/

[ERay]

Roger... thanks for all that info... I have a drawing (exploded) of the system and at least I hope to identify each part based on what you sent...

Thanks again

[Roger Berke]

You will find shop manual with troubleshooting guide on the Aqua-Hot website, here: http://www.aqua-hot.com/b2c/ecom/eco...edManuals.aspx

I am guessing that you have an Aqua-Hot 941-12. Use the shop manual for the AHE-100-00S.

- Roger Berke -
Moderator - Yahoo Hydronic RV Heating Group
http://autos.groups.yahoo.com/group/HydronicRVHeating/

[rhardesty]

Just changed the fuel filter and nozzle and adjusted the two probes. Put it back together and fired it up. It worked fine, but about the last minute of the cool down cycle, there is a popping sound. Almost sounds like microwave pop corn being done. The three relays have clear plastic and I can see that they are not moving. Put my hand on the motor and the silver box that is clipped to the side of the motor and don't feel anything. After I put the cover back on and closed the bay door, tried it again and can still hear it, but very faintly. Maybe it has been doing it all along and I was not close enough to hear it. Called Aqua Hot and the tech said he had never heard of this before.
Has anyone had this sound before ?

[Roger Berke]

Richard

The only relays in your Aqua-Hot are the three relays with the clear plastic cover over them and the relays in the silver box.

The 3 plastic relays control the pumps and the interior fans. The only interface that they have with the Webasto unit is the red wire that comes out of the Webasto wiring harness and connects to the middle relay. If you removed this wire when you did service make sure that you replaced it in the proper place. Drawing is below.[IMG]file:///C:/DOCUME%7E1/ROGERB%7E1/LOCALS%7E1/Temp/moz-screenshot-5.png[/IMG]

If the silver box begins to fail it is not unusual for the relays to click when the box begins to shut down. You should be able to put you hand on the box and feel the relays clicking.

- Roger Berke -
2000 Foretravel U320 42ft
Moderator = http://autos.groups.yahoo.com/group/HydronicRVHeating/