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Topic: Aqua-Hot Heating Efficiency (Read 742 times) previous topic - next topic

Aqua-Hot Heating Efficiency

I have had my coach parked in 20 to 30 degree temps lately, hooked up to 50 amp service, and have noticed that the AH on electrical alone can not keep up with the cold.  The heat exchangers are running, but at best are blowing luke-warm air, and the overflow tank is staying a little bit below midway full.  When I crank up the diesel burner, I get good heat, and the overflow tank shows full when all heated up. 

I spoke with Aqua-Hot, and they said this was normal, as the electrical unit alone can not keep the fluid fully heated with the lower temps; thus the lower level on the expansion tank.  It seems like it was maintaining more heat last year with electricity alone.

I was wondering if anyone had any comments, or are experiencing the same situation.

Thanks, Mike


Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: Aqua-Hot Heating Efficiency

Reply #1 –
We have to keep the diesel burner on for adequate heat as temps are only in the mid 40s during the day and down to low 30s to high 20s at night.
Jeff & Patricia
Rescue dog Molly
Previous Foretravel owner

Re: Aqua-Hot Heating Efficiency

Reply #2 –
Mike,

As stated by Aqua Hot Tech Support, this is normal operation on 30 amp or 50 amp service.  You are trying to heat the inside and the utility basement with only the 5000 BTU capacity of the 1650 watt 120 vac electric heating element.  Now, add the 50,000 BTU capacity of the diesel burner and you are good to go as the temps drops well below 50 degrees.

On the other hand, trade that old used motorhome on a new IH45 and get the Aqua Hot 675 D heater complete with one 5000 watt 120 vac electric element (30/50 amp service) and one 4500 watt 240 vac electric element (50 amp service) which will handle your coach in 20 to 30 degree temps.
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: Aqua-Hot Heating Efficiency

Reply #3 –
Quote from: Rudy –
Mike,

As stated by Aqua Hot Tech Support, this is normal operation on 30 amp or 50 amp service.  You are trying to heat the inside and the utility basement with only the 5000 BTU capacity of the 1650 watt 120 vac electric heating element.  Now, add the 50,000 BTU capacity of the diesel burner and you are good to go as the temps drops well below 50 degrees.

On the other hand, trade that old used motorhome on a new IH45 and get the Aqua Hot 675 D heater complete with one 5000 watt 120 vac electric element (30/50 amp service) and one 4500 watt 240 vac electric element (50 amp service) which will handle your coach in 20 to 30 degree temps.

I understand my 97 u320 is 1400 watts and 35,000 btu's respectively.  Is that correct and what is the model number for my unit?  Any downloadable manuals for it?

Thanks

Bob
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Aqua-Hot Heating Efficiency

Reply #4 –
Mike I have a 95u320 with primus heat and with primus I have electric or propane and the same holds true. Except with propane the generator doesn't run and I use very little propane. Its to bad Foretravel stopped using Primus because for me it works great.
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Aqua-Hot Heating Efficiency

Reply #5 –
Bob

I would expect you to have a Model 431 heater.  Webasto burner rated at 50,000 BTU and 5,000 BTU 120 vac element is all I have seen used.

All manuals at aquahot.com
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: Aqua-Hot Heating Efficiency

Reply #6 –
Quote from: Rudy –
Bob

I would expect you to have a Model 431 heater.  Webasto burner rated at 50,000 BTU and 5,000 BTU 120 vac element is all I have seen used.

All manuals at aquahot.com

Will look.  For some reason I thought mine was 1400 and 35,000.

Seems to draw  15 amp on 110 volt on the link panel 2000

Bob

"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Aqua-Hot Heating Efficiency

Reply #7 –
Quote from: joeszeidel –
Mike I have a 95u320 with primus heat and with primus I have electric or propane and the same holds true. Except with propane the generator doesn't run and I use very little propane. Its to bad Foretravel stopped using Primus because for me it works great.

With the Primus you can have 800w or 1600w of electric, 45,000btu at 95% efficiency with propane, motoraid, or heat from the generator cooling system, or ALL at the same time!
With motoraid its about 100,000 btu propane (both boilers fired) and motoraid combined.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Aqua-Hot Heating Efficiency

Reply #8 –
On our 95 U320 the Aqua-Hot is sufficient for hand and dish washing when operating on only the electric element, but the diesel burner is needed showering and heating the coach. I'm really thankful the Aqua-Hot operates on diesel rather than propane. Diesel is much more readily available and it's really nice to very infrequently fill the propane tank.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Aqua-Hot Heating Efficiency

Reply #9 –
I think the Aqua Hots in different models and years are different sizes.  In our 2001 U320 the AH on 120v when we are hooked up) is good for heating, hot water and reasonable showers in the low to mid 40°s.  Colder than that we turn on the diesel burner as well the 120v (when we are hooked up). Diesel doesn't run very often and adds that extra recovery speed for showers.  In the 30s the 120v doesn't keep up with heating demand by itself.

Roger
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Aqua-Hot Heating Efficiency

Reply #10 –
             Roger;    I think your right about that different sizes and years . In my coach the only time we have to use diesel is for a fast coach heat up . Showers , laundry what ever , electric does the trick for us . The coldest weather we have been in was New Mexico , it was 22 degrees in the morning .  Brad Metzger   
Brad Metzger
2010 Phenix 45'

Re: Aqua-Hot Heating Efficiency

Reply #11 –
I usually turn on the diesel at 40 degrees and it is toasty warm down to single digits when I was out in cold country again in Nov.  I put on diesel heat anytime it goes below 30 as that is much easier to keep everything warm and the bays are warmer that way too.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon