Eurovan Furnace Upgrade

[chrisvolk]

Hi Folks

We're seeking to upgrade or replace the furnace in our '97 EVC. I believe the Winnebago installed unit is from Suburban.

So, is it better to install a new furnace core or replace the furnace all together?

I'm intrigued by the ProPex HS 2000 high efficiency units that GoWesty sells as Vanagon camper replacements.

Please advise!

[TheOneTrueQuux]

[MrPulldown]

I have been very interested in the popular Chinese diesel heaters. Much smaller package size, though it would require a separate fuel source.
_________________
2002 EVC

[chrisvolk]

Hi Folks

Here's an update. Apparently the OEM furnace is a Suburban NT-12, which is outdated. Some RV models like this can be updated with new furnace cores, which are quieter and more efficient. Sadly, this particular model cannot. So Suburban recomments replacing it with a new NT-16 SEQ.

These units appear to be sold out everywhere I've looked. Perhaps the camper van surge is sweeping them from the shelves everywhere, and the supply chain can't keep up.

[TheOneTrueQuux]

[chrisvolk]

Hi Folks

Here's the latest update on replacing the original NT-12S furnace core in our '97 EVC. It's been difficult getting confirmation on what Suburban part number is correct. In fact, I'm still not certain. However, it appears that the 2611A core will work.

What is unclear is whether this unit will have the quieter fan installed. Suburban lists this same core for a number of its heater model numbers, including the NT-16S, NT-16SQ, NT-20S and NT-20SQ. It appears that the "Q" stands for Quiet. Also, the numeral represents the BTU output--16 and 20 represent 16,000 and 20,000 BTUs.

So the unanswered questions are: (1) how can the exact same core be both quiet and non-quiet, and (2) how can this core provide either 16,000 or 20,000 BTUs of thermal output?

I see that the 2611A replacment cores are available from a number of suppliers on the internet. But I'd like to be assured that the upgrade will be worth the $. As of yet, that is an open question...

[TheOneTrueQuux]

[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...

[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!

[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

[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.

[chrisvolk]

[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!

[RiversToTheSea]

[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

[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]

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

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]

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]

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