A/C & Propane

[S3d]

Hey!

Finally our 2014.5 AI is on its way to us

Our main concern is A/C, since here in Kuwait since temperatures are well above 100 in the summer. Also, there is only one place in the country were we could fill up the propane tank. Which obviously seems inconvenient

We need the AI for travel not camping and are looking at major mods to fit our needs.

1. Install an engine driven A/C instead of the maxxair vent.
2. If 1 didn't work, replace the propane generator with the exact same size/power which runs on gas or diesel.

I know those are huge changes but we are desperate.

Any thoughts would be helpful.

Thanks

[Melody Ranch]

I would think that a diesel or gasoline powered generator would be
a relatively easy fix, even over there. Then use an electric powered 15000BTU AC.

[joemikeb]

The possibility of engine driven A/C has been discussed at length in another thread and as I recall pretty well discarded if for no other reason than having to run the engine continuously. Replacing the propane generator with a gas or diesel unit is probably doable, but when you see how tight the mountings are, it could be a real trick to pull off.

The big problem I see in Kuwait is the A/C itself is marginal at best in temperatures much above 90℉. I live in North Texas and travel a lot in the South and Southwest U.S. and in the summer I often have to run both the engine driven A/C and the roof A/C to keep the interior temperatures at a reasonable level. So I would suspect you may be wanting either a significantly larger or even a second roof A/C unit in Kuwait which, of course, would call for additional generator capacity and rewiring the coach for 50 Amp service or more.

[Protagonist]

Originally Posted by S3d

1. Install an engine driven A/C instead of the maxxair vent.

It already has an engine-driven air conditioner built into the dashboard and powered by the main engine. But I think what you mean is a 12v rooftop air conditioner. Fortunately, Mercedes Benz has one as optional equipment on their non-Airstream Sprinters. Shouldn't be terribly difficult to remove the Dometic 120v A/C and install the MB 12v A/C. A generator can power a 12v A/C same as it can a 120v A/C, so no worries there, plus it will run while you're driving.

2. If 1 didn't work, replace the propane generator with the exact same size/power which runs on gas or diesel.

Also fortunately, Cummins/Onan makes a diesel version of their 2.5kW generator, that would be a simple bolt-in replacement using the same mounting brackets and exhaust pipe. The only real change would be having to plumb the new fuel line.

You would still be limited by only having 25 gallons of on-board diesel, and you'd want to plumb the diesel generator so that it draws from somewhere above the bottom of the tank (maybe 1/4 of the height of the diesel tank) so that the generator can't suck the diesel tank completely dry and leave you stranded. You might want to get a hitch-mounted cargo tray to carry jerry-cans of spare diesel, if you go with a diesel generator.

[S3d]

Originally Posted by Protagonist

Also fortunately, Cummins/Onan makes a diesel version of their 2.5kW generator, that would be a simple bolt-in replacement using the same mounting brackets and exhaust pipe. The only real change would be having to plumb the new fuel line.

Only found a 3.2Kw Onan Genset which is a bit larger than the 2.5Kw LP generator.

[Protagonist]

Originally Posted by S3d

Only found a 3.2Kw Onan Genset which is a bit larger than the 2.5Kw LP generator.

I stand corrected. That's the thing about getting old; the more senior I get, the more senior moments I have.

[73shark]

From what I've heard, diesel generators are physically larger for the equivalent output of a propane generator.

I'll guarantee a 15,000 BTU unit will not keep the RV cool in 100*+ temps. That's the equivalent of a window unit.

Since you need it for travel, I'd go for Protag's idea of adding the MB option for rear A/C although I didn't realize it was a 12 VDC unit. I figured it was run off an engine driven compressor similar to full size SUVs rear A/C. The chassis A/C does do a pretty good job of keeping the front of the RV cool tho.

[SmokelessJoe]

S3d

Too bad. You coulda’ bought my Diesel Powered NO PROPANE rig, complete with the MINI for less than your Interstate.








I think joemike might have meant an engine driven power plant, to power a 110 roof top A/C.

I ordered my SPRINTER with both a power take-off and the big 200 amp alternator, thinking I would install an engine driven generator.

That proved impossible. I could not find anyone in North America, including emergency vehicle builders as far away as Florida, who could do it. Even when showed photos of such an installation supposedly done in the UK, they insisted there was no room in the motor compartment and I think they were right. It’s might crowed down there.

But the question remains: why did Mercedes offer the power take off option?

I don’t think that an after market install of the Mercedes rooftop unit will be easily done either, perhaps impossible.

Even the factory installed units are the subject of a class action lawsuit in the USA:

Mercedes Hit by Lawsuit Over Sprinter Model | NBC 6 South Florida


As you’ve discovered, an Onan diesel powered plant is available in the 3.5 kW size. You will need at least that but the plant’s much bigger, much heavier and BIGGER BUCKS. They are also very LOUD, enough to rattle your Interstate.

There is a miniaturized, sound proof diesel made in Switzerland but it is very expensive, $15,000 or more.

[joemikeb]

Originally Posted by SmokelessJoe

S3dI think joemike might have meant an engine driven power plant, to power a 110 roof top A/C.

That is exactly what I meant. Additionally the existing propane generator or a gas version of the same capacity might not be capable of powering a larger roof A/C unit and almost certainly would not be capable of driving a second roof unit (perhaps replacing the ventilator behind the driver and co-driver seats). Installing a generator with greater capacity runs smack into the problem the vehicle and power management systems are setup for a maximum of 30 Amps and the load of a second generator driven A/C would require replacing a substantial portion of the 120V system and power management.

A possible solution might be a stand-alone gasoline or diesel generator mounted externally on a hitch rack and wired to the existing roof A/C and a second smaller A/C unit replacing the vent behind the driver and co-driver's seats.

[Boxster1971]

Originally Posted by Protagonist

It already has an engine-driven air conditioner built into the dashboard and powered by the main engine. But I think what you mean is a 12v rooftop air conditioner. Fortunately, Mercedes Benz has one as optional equipment on their non-Airstream Sprinters. Shouldn't be terribly difficult to remove the Dometic 120v A/C and install the MB 12v A/C. A generator can power a 12v A/C same as it can a 120v A/C, so no worries there, plus it will run while you're driving....

The roof top Ac unit installed by Mercedes still requires the engine driven compressor to operate. The 12V side of these units is only for the various fans used to move air.

[Protagonist]

Originally Posted by Boxster1971

The roof top Ac unit installed by Mercedes still requires the engine driven compressor to operate. The 12V side of these units is only for the various fans used to move air.

That makes sense.

[Boxster1971]

There is a diesel generator that fits under the Sprinter like the Onan 2500 LP units installed by Airstream. Last I heard they are around $8,000, a lot more than the propane unit.

PT-3SV2 | Power Technology Southeast Inc

Sportsmobile is one company installing these diesel generators.

Sportsmobileforum.com • View topic - Generated questions -- powertech generator

They were even listed on Amazon, but not currently available from Amazon.

Amazon.com: POWER TECH PT-3SV2, 3000 WATT, DIESEL GENERATOR WITH ENCLOSURE: Industrial & Scientific

One disadvantage is that it hangs down lower than the Onan unit so it reduces the ground clearance. Here is a thread from the Sprinter-Source forum on one persons installation.

Diesel generator install - Sprinter-Forum

Here is another owner's web site who has the Power Tech diesel generator, installed by Sportsmobile.

Sportsmobile equipment choices

[Boxster1971]

Originally Posted by SmokelessJoe

I ordered my SPRINTER with both a power take-off and the big 200 amp alternator, thinking I would install an engine driven generator.

That proved impossible. I could not find anyone in North America, including emergency vehicle builders as far away as Florida, who could do it. Even when showed photos of such an installation supposedly done in the UK, they insisted there was no room in the motor compartment and I think they were right. It’s might crowed down there.

....

Were you trying to get a 120v AC generator? ... there are plenty of folks installing a second DC alternator to boost the electrical output from Sprinter engine. Both Roadtrek and Advanced RV install such units. In both these rigs they have a BIG invertor and battery bank so you can easily run the roof top 120v AC RV air conditioner while driving and for a few hours when parked.

Here is a copy of the M-B Technical data on the auxiliary drive.

[SmokelessJoe]

Mike,

Yes, I was going to install a belt driven generator. I ordered the 2005 with both the high idle function and the power take off to accomplish that.

It didn't work out and I donated the generator, un-used, to a Mennonite auction.

It was not a sensible idea in any case. You'd have to idle the truck motor at a constant 2200 rpm to make current. How wasteful is that?

Too, when I bought the vehicle, there was no Mercedes support like now. The dealership didn't even know what the power take off or high idle function were for. They only knew the list price.





The heavy battery bank extra alternator idea would not have been the solution in my unique case however.

[Boxster1971]

Originally Posted by SmokelessJoe

Mike,

Yes, I was going to install a belt driven generator. I ordered the 2005 with both the high idle function and the power take off to accomplish that.

.....

Ah - I see you have an older Sprinter - I didn't recognize it on your first post.

Good Luck on selling your rig -- it looks like a sweet setup.