Propane to Natural Gas Appliance Conversion

[ultrarunner]

A natural gas line is going in at the cabin and we are wondering if we should go to the expense and hook up.

Since 1962 propane for cooking and water heating has worked OK.

I asked the Natural Gas company what if anything is involved converting the range and water heater from Propane to Natural Gas... they referred me to the manufacturers which are no longer in business...

I've been told you can run propane stoves and water heaters on natural gas and it only changes the Btu rating...

The white porcelain enamel and chrome range is circa 1962 and like new... the Hoyt Water heater has a all copper tank with lifetime warranty...

Looking for advice...

 

[PILOON]

I am no expert, but as I understand it there is a PSI difference between the 2 gasses.
For the lower pressured gas (I think it is the natural gas) they simply drill out the orifice to a larger size.
Naturally the factory would actually sell a different sized jet, but drilling will do the trick.
Those drills are 'whisker sized' and not your standard drill bits.
Any real practical gas technician can do your conversion.

 

[TripleR]

My father in law owned a propane distributorship and he did conversions by changing the orifices, but I have no idea how it is done, only that it can be done.

 

[uglyboywith11fingers]

I'm on propane here, when we bought a new clothes dryer & kitchen range a while ago, had to get conversion kits (just jets with different orifices) to run them on propane. I would think any tech with a gas ticket should be able to convert your appliances.
If I had the chance to go natural gas, I would jump at it... comparing notes with friends, I think I'd save about a third on my gas bill.
In this part of Canada, home propane costs about 55 cents/liter.
My annual propane bill runs between $2000 - $2500 for heating a 2000 sq.ft 2-storey house, cooking, clothes drying and hot water.

Pete

 

[bucktaker]

Most propane suppliers can do the conversions or supply you with the correct orriffices. not rocket science just changing a orifice in the gas valve but lots a people are intimated by gas..... You cannot run the other gas in the appliance the pressure difference with cause different flames... i think NG is 2psi while propane is 11psi.

whats your propane volume? is their a connection charge to NG? do they have min monthly charges?

 

[k0ua]

I have never done a water heater, but I have done several stovetops and ranges. On the ranges, there is usually a screw valve to turn and an air shutter to adjust back and forth for conversion, and on the stove tops is is "spuds" or "orfices" to change out that have different sized holes. Most stoves have a place to store the other "spuds" on the stove. That is where mine are. Of course some conversion instructions would be nice, but I realize you may not have that luxury. Call the gas man, to be sure.

James K0UA

 

[Tractor Seabee]

This is not an easy DYI project. Convert to NG requires a larger orfice than for propane (LP). There are a variety of ways appliance manufacturers accomplish the flow change. An orfice in the discharge where it meets the air shutter is the most common. Some have a small neddle valve you adjust with a screw driver. Easy if you get new orfices from the original manufacturer; but yours is not available. Try getting the owners manual on-line by after-marketeers; those manuals usually have the orfice sizes for various fuels. The orfice size is an engineered solution based on gas BTU content and the delivery pressure at the orfice. The adjustable ones require a flow meter to set by the engineered flow.

The existing orfice can be drilled out in your case to the new larger size. Your new NG supplier should either have a formula for conversion to their product from LP to determine drill size, have their own service crew, or can refer you to an expert. To drill out the orfice needs to be removed so chips can be cleaned out. The new hole has to be straight, round, and have no burrs inside or outside when done. It is a precision process. The NG supplier can also advise on any other safety device changes current codes require. That subject has evolved exponentially over the last 20 years.

DANGERS: 1. Too large an orfice may cause overheating of the appliance, remember, the burner and surrounding materials are engineered/designed for a specific burner BTU output. (2) To much gas and the air adjustment may not be large enough and cause smoking of the flame. (3) Too small an orfice and the BTU output will not get up to design.

60 years ago when I worked in AZ we did a lot of this conversion work as NG pipelines were installed in the state. Manuals were not heard of much back then. We got our info from the gas companies and were very successful. We even did the reverse by peening the large orfices with a hammer and punch and redrilling to the smaller size for LP. A lot of water has gone under the bridge and those formulas are no longer in my brain.

Ron

 

[CurlyDave]

We have a fairly expensive Thermador cooktop which a local supplier installed in our propane house configured to run on natural gas. By the time we figured out that the bottoms of the pots shouldn't be covered in soot all the time, the supplier disclaimed all responsibility.

I ordered a natural gas to propane conversion kit from Thermador, but many of the orifices were the wrong sizes for what was called out in the manual. By mixing and matching both the sets of air and gas orifices, I got it almost right, and the soot situation is much better, but both Thermador and the local supplier have permanently lost my business.

 

[Egon]

In many areas your insurance, Utility or local codes will not allow the switch. You may have to install the required natural gas burners and use a certified installer.

The Propane has more BTU capacity than Natural gas.

Curly; From your post it is assumed you have gone from Natural Gas to Propane. If so, the soot may be from excess fuel cause by improper pressure or orfice size which you are already familiar with. If it's possible make a check on the supply pressure.

I do have a little container with different orfice sized drills that have seen use a time or two. The drill bit diameter is quite small and will not fit in regular chucks.

 

[Ramseymafia]

I haVe done many conversions,water heaters ,heaters,just change the orofice and it will work fine