For the love of CNG

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Kevin Henderson

Ever since I purchased Pau Hana, one of the items that came out in the survey was the Hillerange Stove/Oven.  The stovetop has worked fine but the oven has never worked.  I had toyed with the idea of converting to Propane but considering the expense, and after researching discovering that the CNG is much safer, I made the decision to troubleshoot my oven and see if I could get the thing working on my own.  Although finding a CNG dealer is difficult, it's not impossible and I'm lucky to have a dealer her in San Diego. 
I went to the Sure marine website linked here and used their online troubleshooting guide.  I found it very helpful and I made the determination that my Mercury Thermocouple switch was bad.  While this part is not easy to get, Sure Marine told me that they could send me a rebuilt unit provided that I send them my old one, for $178.  I dug into the oven and tore my thermocouple switch out.  I then shipped my old unit out and in very short time I received my replacement switch.  This past weekend I went about re-installing the new switch (still following Sure Marine's excellent information).  Feeling confident with my work I lit the stoves right burner and then went to light the oven and the pilot lit and the oven burners came on perfectly.  It sounds silly but one of the things the Admiral has been looking forward to doing is baking some yummy Chocolate Chip cookies.
I realize that that propane probably delivers higher BTU's and a drier heat but for the price I am very, very happy to keep my lowly CNG stove/oven going for the foreseeable future.   :thumb:   :abd:   

http://www.suremarine.com/stove-repair.htm
The sail, the play of its pulse so like our own lives: so thin and yet so full of life, so noiseless when it labors hardest, so noisy and impatient when least effective.
~Henry David Thoreau

chuck53

When I bought my boat almost 3 years ago, it had CNG.  I'm very happy with it and have no desire to convert to propane.  yes, it is a challenge to find CNG, but I only have to do it every other year or so.

Ron Hill

Kevin : The only reason to convert from CNG to propane is if you do some long range cruising into areas where CNG is difficult - impossible to get!

I've never looked for a thermal couple, but I'm sure that you can get a cheaper (exact) replacement from a plumbing supply.  They (TCs) are used in most gas kitchen stoves, gas log fireplaces and gas water heaters. 

A thought
Ron, Apache #788

Indian Falls

Hey, just wondering... could you source the info you found showing CNG is safer than propane?

I've had propane in my home for 28 years... so needless to say my eyebrow went up when I saw this post.   Natural gas and propane are interchangeable fuels in homes, with a bit of orifice change, but otherwise fairly equal in "blow things up" terms.  I've always thought the opposite cuz CNG is a scuba tank at 2500lbs full of mostly methane.  How is that safer?  Did you see the youtube video where they attempted to blow up a boat with a propane leak of abrupt proportions?   It failed, on the second attempt they had to specifically address fuel air mix ratios to get a muffled POOF, well of course fire occurred shortly thereafter.   Bottom line they cheated!  They had to create conditions that would almost never occur.  Just Saying...
Dan & Dar
s/v Resolution, 1990 C34 997
We have enough youth: how about a fountain of "smart"?

Kevin Henderson

 Really the only reason I stated that it could be safer is due to the specific gravity of CNG over propane.  CNG will rise to the atmosphere while LPG will sink and possibly settle in the bilge.  (I grew up in an area where many homes use propane delivered from large tanks out in the back yard)  Fortunately most homes don't have a "bilge" where harmful vapors could collect. 
As for citing my source.  Among others, "Good Old Boat" did a wonderful analysis of all six commonly used galley fuels.
Didn't mean to startle anybody... just stating what I thought to be best for me or others that may already be using CNG and want to stay with it.  :abd:

http://www.goodoldboat.com/reader_services/articles/cookingfuels.php
The sail, the play of its pulse so like our own lives: so thin and yet so full of life, so noiseless when it labors hardest, so noisy and impatient when least effective.
~Henry David Thoreau

Ralph Masters

Very good information Kevin.  I'll be over for a cookie later.

Ralph
PS - Good to have you back in the fray chief.
Ralph Masters
Ciao Bella
San Diego
Hull 367, 1987

Albreen

Hi Kevin - I hadn't seen the Good Old Boat article before - thanks for sharing the info. Like you, I decided to keep CNG primarily due to our short season and day sailing with occasional extended week long trips. The delay in getting CNG doesn't present any real on board living issues. The plus side of CNG being "a lighter than air" gas is it doesn't require a dedicated locker with an overboard drain in the event of a leak. I would agree with Ron in that if I were cruising longer term, I would probably want to change it out due to it being so unavailable. Maybe someday!     
Paul Leible
1987 C34 "ALBREEN", SR/FK, M25XP
Sailing Lake Champlain

Stu Jackson

Paul, the regulator on the CNG tank has a fitting to run a hose OUTSIDE.  I've been meaning to do that since we bought our boat in 1998.  It's on my survey and I will have to do it, later rather than sooner.   :D

Kevin, have you seen the CNG refill adapter "How To Build One" in the C34 Tech wiki?  Then you can find CNG refill stations, like gas stations, in your area.  Instead of $24 or more to swap tanks, it only costs $4 to refill.  We have a econd backup tank that our PO installed in the locker under the port settee seat just forward of the holding tank, with a large hole drilled in the forward bulkhead, the handle fits in under the V berth drop down door.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Albreen

Stu - Yes, I do have this hose and it travels up the 3" fresh air hose coming from the clamshell vent near the stern that terminates behind the engine. This hose is the fresh air supplier for the blower hose further forward on the other side of the compartment. (Hope this makes sense) I've assumed this setup would be sufficient for a leak because the gas will rise up and out of the clamshell vent but I have wondered if should be setup differently. FYI - I also put a Xintex solenoid inline per the recommendations of the surveyor during the pre-purchase survey. If I recall, the solenoid required being placed beyond the regulator and not on the tank side as you would with propane. All is working well a few years now.

The adapter is a great idea I haven't done yet.
Paul Leible
1987 C34 "ALBREEN", SR/FK, M25XP
Sailing Lake Champlain

Stewartn

Ron Hill and other East Coast users of CNG. Good friend going to Chesepeake this Spring with CNG aboard. Can yiou help with places to re-fill on the Bay? It's difficult here in the North East. Thanks Much.
Stewart Napoleon, Hull #1472, Desiree
Greenwich, CT

mregan

Not the hijack the thread but can you convert a propane cooktop to CNG.  The '86 I bought had a CNG stove which didn't work.  I got rid of the stove and was going to replace it with a cooktop.  I can only find propane ones.  Was wondering if I could convert it to CNG.

Stu Jackson

Propane to CNG:  call Seaward and ask Dennis.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Indian Falls

Most homes do have a "bilge".. it's called a basement.  Besides, in a boat you are still in a confined space.. in my opinion it matters not if your fumes are laying low or collecting high under and inside your lazarettes and galley cabinetry or even the ceiling where your bilge ventilation fan would do you no good.  I'm not trying to debate anyone, it's just that many times I see propane being stigmatized as more dangerous and it isn't, it's only different.  I would be a bit more uncomfortable around a high pressure tank of CNG than gas grill tank, but that's just me.
Dan & Dar
s/v Resolution, 1990 C34 997
We have enough youth: how about a fountain of "smart"?

Stu Jackson

#13
The high pressure CNG tanks are like oxygen bottles:  heavy and solid, but harder to move and replace than simple propane tanks.  I have no worries about them on the boat.  Have propane at home for the BBQ.  Got 'em both.  Neither is an issue.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Ron Hill

mre : I found that your local gas company can give you the "what's needed to convert" info.

Give them a try.   
Ron, Apache #788