Eurovan Furnace Upgrade

[HeyCrutch]

[kourt]

Whatever I can do to make The Samba better than some Facebook group is worth the effort.

kourt

[Kulshancruising]

Just want to pop in to say thanks to Chris and Kourt for sharing their furnace upgrade info here! Really appreciate the expanding knowledge base for EVC maintenance/upgrades taking place here. My furnace suddenly stopped working and went ahead and swapped in the new core and a digital thermostat as mentioned here. y'all made it sound way easier than it was for me though! I ended up having to replace the 90 degree gas connection from the furnace as well as the wiring disconnect, and my wire gauges were too big for the digital thermostat. So glad I did the furnace core and not just the thermostat-found more dead mice inside the furnace . Thanks again guys, you saved my winter camping/skiing season.

[kourt]

Howdy Brian,

The ducting you see is original.

The device you see is a Renogy inverter.

kourt

[bcolins]

[mikemtnbike]

Air temp when returned from New Year's Day mtb ride - 34 fahrenheit. Air temp in van by time finished changing clothes - 52.

100% worth the noise. I had some issues with the core replacement, sail switch wasn't activating on the new unit, had to put the one in from the old core, but now it lights and stays lit as soon as I move the thermostat. LOVE IT.
_________________
1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[kourt]

One more update on this furnace replacement:

I just returned from a weeklong trip to Palo Duro Canyon in the Texas panhandle, White Sands National Monument in southern New Mexico, and Guadalupe Mountains National Park in far west Texas.

The nights were consistently in the 20s during this trip.

We were well prepared with good bedding, sheets, wool blankets, and top quilts. The windows have radiant barrier shades, and the poptop had Fancher's insulation.

In the evenings we set the thermostat to 60 degrees and were comfortable. At night we would set it to 45 degrees. I recall hearing the heater fire up around 4AM every morning when the temps finally got down below 45 in the van.

I was always in the upper bunk, but would hear the heater fire up. My wife was down below and most definitely heard it, but she was comforted by the prospect of the van's interior being kept at a consistent temperature threshold. This made everything work for us.

On my last two nights I wore earplugs and never heard anything. My wife is not a fan of earplugs, so she will just have to enjoy the white noise of the heater in her downstairs bed.

This Suburban furnace is a noisy, powerful beast, better than the Propex in my old Vanagon. It's loud, but we're happy to have it.

kourt

Below: Oliver Lee Memorial State Park on a cold 25 degree morning, near Alamogordo, NM. It's warm inside.

[kourt]

Just an update to this thread:

I took out the new heater over the summer and wrapped the housing in butyl backed sound deadening mats in an attempt to reduce the sound profile of the Suburban heater. It's been a hot summer, and only today did we get a morning cold enough for me to test the heater.

Before sound deadening:

Baseline (nothing on): 33 dB
Furnace on and blowing: 55 dB

After sound deadening:

Baseline (nothing on): 31 dB
Furnace on and blowing: 52 dB

One could argue that the difference is in the lower baseline. Not much of an impact. In my non-empirical analysis, it all sounds the same.

When I really need it, though, I am sure I will be happy to use earplugs and be warm with my Suburban heater at the same time.

kourt

[kourt]

The new furnace is installed.

It was pretty straightforward. If you bump the igniter and push it out of calibration, you'll need to Suburban literature to fix that:

Testing the sound:

Baseline (nothing on): 33 dB
Furnace on and blowing: 55 dB

That's not an empirical improvement. It mostly sounds the same to me, but there is less high and midrange howl. We'll see how it works. I am thinking of eventually putting some sound deadener around the outside of the steel heater cabinet. My van is a 2001 EVC and maybe the furnaces of that year were already quiet by Suburban's standards. The important thing is that, when someone complains about the heater noise, I can say it's the quieter model, and we'll pour the whiskey and accept our outcome.

I'm still pleased with the work. I was able to clean up the furnace cabinet, and the old furnace was very rusty.

kourt

[kourt]

The new Suburban 2611A furnace core arrived at Home Depot yesterday, and I picked it up today. I took the sound reading on the old furnace today. The van was closed up, and sound was measured near the aft sliding door of the rear closet, where my head would be.

The baseline (furnace off, nothing running) measurement was 34 dB.

When the old furnace was running the measurement was 54 dB.

Honestly, I have my doubts about a big improvement in sound reduction, because I think a lot of the noise is conducted energy from the furnace body, through the bedding, and into my head. But I hope I'm wrong. This is still a new and more powerful furnace, so it's a win either way.

I hope to get the new furnace installed this weekend. As stated earlier in this thread, this appears to be a simple slide-in installation. The heat exchanger intake and exhaust are slip fit, and I doubt I will be using the included chrome vent cover.

kourt

[kourt]

What I will do: take a decibel meter and measure before/after. Stay tuned.

kourt

[mikemtnbike]

I can literally feel the money straining to get out of my wallet to buy this. Thanks chrisvolk!
_________________
1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[kourt]

Sweet. That's all the justification I need.

I've ordered it online.

Hopefully this improvement will mitigate the "should I be warm, or should I have quiet" debate on a cold night.

More dollars flying out of my wallet!

kourt

[RiversToTheSea]

[chrisvolk]

Hi folks

The results are in--the new furnace is a big improvement. 50% quieter. The upgrade from the original equipment was a 100% success!

[chrisvolk]

[1961tbird]

Ditto for me regarding the eventual conclusion.

I was in upstate New York last weekend. Lows were mid 20s with wind chill. Pulled down top at night and set at 60F. Furnace struggled through the night turning on quite a bit so the extra BTUs would be helpful. Quiet would be great too but I have gotten use to it.

[kourt]

I'm glad for this thread. The missing piece, of course, is when you fire up the new furnace and tell us if it is actually quieter.

I used my 2001 EVC furnace for the first time in December. I was sleeping in the lower bunk and it was like a hair dryer was on low speed down there--pretty loud, and hard to sleep through.

My old Vanagon had an aftermarket furnace that was mounted outside, under the van, so it was pretty quiet--but not nearly as powerful as this Eurovan furnace. I really want to make this EVC furnace better and that starts with making it quiet.

So I really hope you'll test yours out and give us the feedback on how it sounds. I love that you shared with us how to buy it easily--Home Depot has plenty in stock.

Did you have to remove the entire furnace housing to swap the core, or were you able to make a pretty clean swap with minimal fuss?

Hope to see your reply soon--thanks again.

kourt

[chrisvolk]

Update - Hi Folks

I was able to order a replacement core for our '97 EVC furnace (Suburban Model NT-12S) from Home Depot for $444 delivered. It's actually the core for the NT-16S, which has an output of 16,000 BTUs vs. the 12,000 BTUs produced by the NT-12S unit. Note that the Suburban stock number for this replacement core is 2611A with a corresponding part number of S6U01-1722.

The new core has plastic fan blades rather than the metal ones in the NT-12S--I'm hoping it's a bit quieter. (Note that I have not yet fired up the new installed core because my van is still dry docked for the winter.)

The search process was maddening, particularly because Suburban repeatedly told me that no furnace core upgrade was available...or that the NT-16S unit would not fit in the installed metal furnace cabinet, which housed the OEM NT-12S unit. Wrong on both accounts.

I also installed a new cabin thermostat from Suburban, which shipped from Amazon for under $20. You can find other references to this upgrade elsewhere on the web.

In case anyone is interested, I'll be glad to sell my old NT-12S core, which is in fine working order--I did this upgrade to get a bit more heating power (we reside in the Rockies) and a quieter furnace fan. So feel free to ping me if you are interested. I don't have a price in mind at this time.

Thanks for listening. I'm happy to answer questions!

[chrisvolk]

Hey thanks for the explanation. I get it. What I'm still keen to understand is whether this replacement core--the 2611A--is a quiet unit. I'm guessing not. I can't find any reference to this or the "Q" code in Suburban's documentation...