Author Topic: Question on bay heat on aqua hot  (Read 2672 times)

Dwight Lakusta

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Question on bay heat on aqua hot
« on: September 29, 2019, 04:20:15 AM »
Hi everyone, question for you guys.  Just wondering what controls the water bay heat?  I’m told here is a thermostat down there that controls it.  The question, do I need to have any thermostats going in the house area for it to work?  If I keep my diesel heat off, and turn on the electric switch for the aqua hot, will it heat the water bay like that and not heat the house ?  Or do I need the diesel switch on as well? 

Stan Simpson

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Re: Question on bay heat on aqua hot
« Reply #1 on: September 29, 2019, 05:52:42 AM »
The water bay thermostat will turn on the Aqua Hot at approximately 43 degrees F, but only if the diesel burner is on. What I do, when the coach is sitting next to the house, and temps drop, is turn on the furnace heat (the diesel burner) and set it to 45 for the inside of the coach, so it will already be on if the temps in the water bay reach 43 or less. If you have an Aladdin, you can look at outdoor temps and the basement temp on your screen that is for Tank readings. Its at the bottom. I monitor it closely while its in cold weather next to the house before we leave for Florida. Generally...generally, if the inside of the coach is 50 degrees, the basement temp will be the same.
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Fred Brooks

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Re: Question on bay heat on aqua hot
« Reply #2 on: September 29, 2019, 02:24:27 PM »
   As Stan suggests, Keep your Aqua-Hot diesel switch on. The heat exchanger is mounted at the top inside of the water compartments that house your holding tanks, (last compartment in front of your drive axle) Make sure your bedroom t-stat is set for "heat" and when the temp in water bay carpeted compartment calls for heat, the heat exchanger and fan will come on. Note: you will see 2- 3" black registers that also blow warm air into the adjacent storage bay to warm the fresh water tank. Fred
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Dwight Lakusta

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Re: Question on bay heat on aqua hot
« Reply #3 on: September 29, 2019, 09:12:03 PM »
Thanks fellas. I’ll try that out today.  It has been dipping down here, -7 degrees last night.

Dwight Lakusta

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Re: Question on bay heat on aqua hot
« Reply #4 on: September 30, 2019, 04:46:26 AM »
Alright, well it seems to be working as it should.  46 degrees on the Aladdin.

Here is my idea. Can I cut out the existing temperature sensor and put in a thermostat inside the bay that I could control and turn the temperate higher than the 43 it is set to?  What does it look like? Where is it located?

Stan Simpson

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Re: Question on bay heat on aqua hot
« Reply #5 on: September 30, 2019, 04:53:50 AM »
I'm wondering why you would want to do that?
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Fred Brooks

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Re: Question on bay heat on aqua hot
« Reply #6 on: September 30, 2019, 02:34:29 PM »
    Dwight, not sure why you would want to change it unless you feel there is going to be collateral damage before it comes on. -7 degrees is dangerous and too hostile for a motorhome in my opinion. If your coach has the water distribution manifold in the water bay, it will freeze for sure at that temperature.
   To change the compartment thermostat setting, remove the carpeted access panel on the curb side compartment forward of the dual tires. Look for a capillary tube (about 1/8" copper tubing) somewhere above the top holding tank. Trace the tubing to the "thermostat" It has a black knob on it. There is no label on it to indicate what setting it is adjusted to on some models. Turn it clock-wise to raise the setting. Monitor the temperature with a portable thermometer to see the results.
  If you are not happy with the results, may I invite you to Arizona for the winter. Blessings, Fred
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2000 Marquis, Jasper
C-12 Wild Cat (U of A)
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Proverbs 3: 5 & 6

David T. Richelderfer

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Re: Question on bay heat on aqua hot
« Reply #7 on: September 30, 2019, 02:44:33 PM »
Man o' man... in two weeks it's gone from summer to early winter here.  Yesterday our overnight temperature was 40F and this morning it is 39F.  So I've been reading this thread with interest and I decided to flip on my Aquahot yesterday morning before heading to the golf course - both the electric water heater element and the diesel burner plus I turned the inside thermostats up to 50F.  At the time, 6 am, the coach interior must have been above 50F because the furnace fans did not come on while the Aladdin said the basement was also 50F+.  Anyway, when I get home five or so hours later, the basement temperature was 94F as noted on the Aladdin.  In the past, when I turn the interior thermostats up in cooler weather, the basement after a few hours heats up to near 100F.

My question is given that the basement heater turns on around 40F, at what temperature does it turn off?  I realize the inverter sheds some heat into the basement too.
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Fred Brooks

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Re: Question on bay heat on aqua hot
« Reply #8 on: September 30, 2019, 03:38:17 PM »
   Dave, good question! Our Marquis's are insulated as good as it gets. Here is the reality of cold temperature effects on my coach in Tucson AZ. It has to get down below 21 degrees more that 2 days in a row with a day time temperature of 40 degrees with my coach parked out in the open before damage occurs. The first thing that breaks is the plastic rings behind the knobs of the water manifold in the water bay. When the forecast calls for temps down below 25 degrees is when I turn on my hurricane to diesel and set my thermostat to heat and set it at 45 degrees. Fred
Fred & Cindy Brooks
2000 Marquis, Jasper
C-12 Wild Cat (U of A)
2014 Honda CRV
Proverbs 3: 5 & 6