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Topic: Heating options - propane, AquaHot, Primus (Read 1414 times) previous topic - next topic

Re: Heating options - propane, AquaHot, Primus

Reply #25 –
The main benefit I see from the AH is when you travel in cold weather. You can just use engine heat to heat the coach. It us quieter too when you are camping.  Both will keep you warm and both have enough water thru put to keep everyone happy. Now that I went to AH, I would never not have it.
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

Re: Heating options - propane, AquaHot, Primus

Reply #26 –
Quote
as long as I can convince the DW that 10 gallons is plenty of water
Really much more than 10 gallons as you are mixing with cold at the faucet.

One issue that hasn't been addressed is the current draw of the two systems which becomes important if you like to dry camp. I asked Rudy about this awhile back and he provided me with the following numbers (Thanks, Rudy):

Fans - 2 amps each (in our 320 we had 1 bedroom, 1 bathroom, 2 basement, 3 living room)
Pumps - 2 amps each (there are 3)
Burner - 6 amps
Controls - 50 milli amps (switches, thermostats)
Electric Element - 13 amps
So can be 24 amps when all up and running together.  Will be less as the interior thermostats and burner control thermostat are satisfied and cycle the components they control off.

The furnaces on our 95 draw about 5.7 amps each. It would be really interesting to have a side to side comparison of an AH vs. LP furnace current comparison. If both rigs had Trimetrics, wouldn't be too hard. Anyhow, I'm thinking for dry camping the LP setup would be better.
jor



93 225
95 300
97 270
99 320

Re: Heating options - propane, AquaHot, Primus

Reply #27 –
At an aside, for nighttime comfort, we find having the door to the bath closed and AH on 68F in the bedroom the AH never comes on. Body heat heats the room. This is good at least down to 50F outside.

Then having had the AH on the evening before, the existing hot water heats the bathroon nicely with the door to the salon closed.

Making stovetop espresso and capuccino with propane gives a good start to heating the salon.

best, paul
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: Heating options - propane, AquaHot, Primus

Reply #28 –
Quote from: Lon and Cheryl –

I have only read about one other Foretravel that had this installed. It was a 95 U320 that the owner of Justin Boots ordered. Foretravel wanted a system that would heat the hot tub that was installed in his coach.

There was at least one other primus coach.  The original prototype unicoach with the series 60 Detroit motor in it.
"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: Heating options - propane, AquaHot, Primus

Reply #29 –
I also have a 95 u320 with primus and it is great even heat quiet and very efficient
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Heating options - propane, AquaHot, Primus

Reply #30 –
Jor,  if you are dry camping you would not have the 110v heater on.  At a low temp of 40 degrees overnight, we never have the BR or Bath on, set the LR to 65° (68° during the day), basement is set to just under 40°.  With the heat from the AH in the basement, this is likely to never come on. So 3 fans in the LR and one pump run for 5 minutes or so maybe 2 or 3 times an hour.  The diesel burner might come on once or twice over night.  You need to look at what zones are on and for how long to get amp hours.  Same thing with your LP furnaces and water heater.

The colder it gets the more parts will run and they will run longer.

It all boils down to how many amp-hours to stay comfortable + LP or diesel. 

I've been looking at speed controllers for the AH fans.  Lower speed means lower amp draw and lower sound levels.  The fans would likely run longer but perhaps less often.  Something I want to try.  PWM speed controllers are cheap.

However we do it, stay warm and comfortable.

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

Re: Heating options - propane, AquaHot, Primus

Reply #31 –
The Country Coach my friend has that we did the re & re of Aquahots in, also has a secondary hot water tank powered by 120v, that is as well as the one in AH. This was another 10gallon one so they have quite an amount of hot water if needed. It  (wiring and solenoid valve problem) caused us a lot of consternation as we were not aware of it at time. We did not know either were the heck it was hidden so finished up pulling lots of cabinets apart to trace plumbing. Finally found it so bypassed the wiring to control board till he could pick up another one on his way back south. I learnt a lot about the AH even though we do not have it.
John H
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Heating options - propane, AquaHot, Primus

Reply #32 –
Quote from: Home2fromHastings –
Jor,  if you are dry camping you would not have the 110v heater on.  At a low temp of 40 degrees overnight, we never have the BR or Bath on, set the LR to 65° (68° during the day), basement is set to just under 40°.  With the heat from the AH in the basement, this is likely to never come on. So 3 fans in the LR and one pump run for 5 minutes or so maybe 2 or 3 times an hour. 

Exact thinking from great minds it seems. The 91 Marquis I sold had hot water heating with four zones and fan speed controls for each zone.  Yes 91's.  Way advanced coaches.

Be easy to install I bet?

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: Heating options - propane, AquaHot, Primus

Reply #33 –
Quote from: Caflashbob –
There was at least one other primus coach.  The original prototype unicoach with the series 60 Detroit motor in it.

The original owner of my coach told me that the 1st 1995 U320 made was for Mr. Fore. That must be the prototype your speaking of. The coach I have was one of the first and used in the 1995 U320 brochure that introduced the then new Uni-bus design (would live to see that brochure).

The Justin coach sounds like a VERY interesting custom build. Do you remember anything about that coach?
Sure would be interesting to know where these models are now.

Looks like only a handful were equipped with the Primus, all probably at the beginning of the 1995 U320 production. After that they must have decided the Aquahot was a simpler install and the way to go in the future.

Thanks for your EXCELLENT RECALL! You sure can fill in the missing pieces.
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: Heating options - propane, AquaHot, Primus

Reply #34 –
I just checked the manual for the Primus system, here are a few specs.

DC power usage- standby= .04 watts
                                        2.2 amps during ignition (.05 seconds )
                                        2.5 to 3 watts while running

propane use- 1.08 lbs of propane per hour

2 boilers = 21,500 btu/h each total=43,000btu/h (95% efficiency)

At -20 below will heat a 300 hp Cummins in less than 1 hour to start temp.

There is a generator heat exchanger that transfers generator heat to the coach heating system. A generator pre heat function is also used in the Primus system.
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.