I wrote in regarding needing to convert the Vermont Castings Radiance 2560 from Propane to natural gas. This stove is about six thousand to replace, so the cost of totally refurbishing parts seemed reasonable. The bray gas injector for the main burner being no longer available, and no one seemingly having another unit who could trade out the orifices with me, I did drill out the ceramic bray injector with success.
I did my calculations ... based on the number of BTU of the unit and the size of opening needed for Natural gas. Propane orifices are smaller than natural gas, because propane is delivered at higher pressures. So going from Propane to natural gas requires drilling out the orifices to allow more gas through. There are many factors that affect how big the flames will be, so I was taking my best educated guess at this.
Next I went to the PMC Supplies (a seller of supplies for jewelry related projects) to order a pack of diamond drill bits. Many times crafters who are drilling through stones to mount them need these diamond drill bits, and there is helpful information on drilling hard objects to be found on their website.
I ordered a "5 Pack Diamond Coated Drills size #61" for $12.95.
Item# 28.0530/61
The drill bits were so tiny that they would not easily fit in the chuck of my drill press. I am sure there are tiny chucks that can be used, but I did not own one.
I found some thin metal wire like you buy in a jewelry making section at your local hobby store, or Michaels... looks like thread on a spool but made of wire. I carefully wound this thin wire over the shaft end of my drill bit by hand, round and round in a tight set of coils, and then back again over the first set of windings to increase the drill bit size sufficiently that it would grab in my chuck. (see photo). I suspect you could use any fine wire, even fine soldering wire or wire from inside a long twist tie if it were cleaned off.
I got out a dish pan and filled it with a few inches of water, just enough to cover the head of the bray orifice which I clamped into the a cheap drill press vice, with the ceramic part with the holes facing upward. The vice, orifice and all was submerged into the dish pan of water.
I carefully lined up the bit over one of the holes as well as I could manage. The bit flexes a little, it is so thin, and the preexisting hole tends to self center your bit, but I took my time and tried to get it as perfect as the eye could manage.
The instructions with diamond bits are to barely press as you drill, a very light hand, touch down onto the ceramic, then raise the bit up to allow it to cool and wash away the debris its accumulated, and repeat this motion over and over, gradually drilling the hole out larger. I found the ceramic does not feel that hard under the pressure of a diamond bit, you are never bearing down heavily, it takes a very light touch.
The water got a little cloudy as I drilled out the ceramic and the bit punched through unexpectedly quickly when I broke through the end of the ceramic, but the very light pressure seemed to allow time to compensate..... and there I was... one done. I jumped up and down a couple times with a smile, "Yay, I got it!" But there are a bunch of holes, you know so I line up the next one and went forward drilling each one.
I managed to drill out all but one of my holes, and in that hole, I snapped off the diamond bit. Bummer.... I wound up the wire on a second drill bit, and tried to redrill the hole (nothing to lose at that point). the bit went into the ceramic at a slightly different spot, it just went down beside the old hole (now plugged with my broken bit) and it drilled out an alternate hole right beside the old one. Well... same amount of gas will go through, so no harm in trying this out in the stove, I reasoned.
In hindsight, I think I should have left one or two holes undrilled to verify flame size, and only drilled out as many as were needed to achieve the flame I wanted. But in the end I was satisfied with the appearance of drilling them all out with the #61 drill bit. Photo below.
So what I was missing with this stove was the first piece of direct venting, the collar that allows you to attach onto the direct venting. I tried using a loose fitting alternative just for testing and the results were disappointing, a limpid set of gas flames came out of only the front set of holes in the newly cleaned burner with a fresh gasket, but no flames out of the rear sets of holes. But here is the deal, your venting does affect how much flame comes out of the burner. My stove had a restrictor plate in the flue opening, which is used when you have a very tall chimney heading up through a roof. The taller chimney exerts a much stronger draw than the short one, but I had only a short piece of direct venting for testing. With the loose fitting vent collar, we were not getting hardly any draw up through the stove. The restrictor is just a flat metal plate with a smaller size of hole drilled in it, that narrows the opening so less gas and air can go up a very tall vent. It is removed for the shorter flu application where the venting goes up a few feet and turns to go out through the wall.
I took my restrictor plate out (3 phillips head screws hold it in) and retrofitted a vent adapter that really did allow a proper, tight, fit onto the direct vent pipe above, which ended just below the 8 foot high ceiling in the shop, so fairly short. I relit the stove. This time the additional upward draft created by the venting caused the flames to appear in all the holes of the burner, and they were just in the size range I expected to see for a gas fireplace. I took a quick photo without any logs in there, and this was on the low flame setting of the gas valve. The high flame setting was only a small amount larger. I may opt to change the air shutter (in the air intake pipe below the gas burner), to reduce yellow flame a little, but this is the initial shot with the air shutter set about half way open.
I want to comment about alternative parts. I wanted to replace both my gas valve and my pilot assembly with this old stove. I found the natural gas valve at fire-parts.com and ordered
FP2007
It cost $94. in March of 2024 on this website.
I also wanted to replace the pilot assembly where your thermocouple and gas pilot flame reside, and ran into the inevitable, No Longer Available thing... but I discovered that there is an alternative one that can be used with excellent results. This was the Heat N Glo Heatilator Quadra Fire Natural Gas Pilot 485-510A 4021-736
It comes with a new natural gas pilot orifice sized correctly for Natural gas. Mine cost about 50 bucks on ebay, but I notice it is available on amazon.
I'll try to attach a few photos to help educate any other person considering doing their own conversion. For sake of liability, I must say that I don't recommend doing this as a homeowner, or as an unlicensed person. The info may be helpful if you can work with someone who is licensed to make this conversion. Today I hope to start up the stove and leave it running long enough to verify if my fan motor will kick on and verify that it is not too noisy.
I did my calculations ... based on the number of BTU of the unit and the size of opening needed for Natural gas. Propane orifices are smaller than natural gas, because propane is delivered at higher pressures. So going from Propane to natural gas requires drilling out the orifices to allow more gas through. There are many factors that affect how big the flames will be, so I was taking my best educated guess at this.
Next I went to the PMC Supplies (a seller of supplies for jewelry related projects) to order a pack of diamond drill bits. Many times crafters who are drilling through stones to mount them need these diamond drill bits, and there is helpful information on drilling hard objects to be found on their website.
I ordered a "5 Pack Diamond Coated Drills size #61" for $12.95.
Item# 28.0530/61
The drill bits were so tiny that they would not easily fit in the chuck of my drill press. I am sure there are tiny chucks that can be used, but I did not own one.
I found some thin metal wire like you buy in a jewelry making section at your local hobby store, or Michaels... looks like thread on a spool but made of wire. I carefully wound this thin wire over the shaft end of my drill bit by hand, round and round in a tight set of coils, and then back again over the first set of windings to increase the drill bit size sufficiently that it would grab in my chuck. (see photo). I suspect you could use any fine wire, even fine soldering wire or wire from inside a long twist tie if it were cleaned off.
I got out a dish pan and filled it with a few inches of water, just enough to cover the head of the bray orifice which I clamped into the a cheap drill press vice, with the ceramic part with the holes facing upward. The vice, orifice and all was submerged into the dish pan of water.
I carefully lined up the bit over one of the holes as well as I could manage. The bit flexes a little, it is so thin, and the preexisting hole tends to self center your bit, but I took my time and tried to get it as perfect as the eye could manage.
The instructions with diamond bits are to barely press as you drill, a very light hand, touch down onto the ceramic, then raise the bit up to allow it to cool and wash away the debris its accumulated, and repeat this motion over and over, gradually drilling the hole out larger. I found the ceramic does not feel that hard under the pressure of a diamond bit, you are never bearing down heavily, it takes a very light touch.
The water got a little cloudy as I drilled out the ceramic and the bit punched through unexpectedly quickly when I broke through the end of the ceramic, but the very light pressure seemed to allow time to compensate..... and there I was... one done. I jumped up and down a couple times with a smile, "Yay, I got it!" But there are a bunch of holes, you know so I line up the next one and went forward drilling each one.
I managed to drill out all but one of my holes, and in that hole, I snapped off the diamond bit. Bummer.... I wound up the wire on a second drill bit, and tried to redrill the hole (nothing to lose at that point). the bit went into the ceramic at a slightly different spot, it just went down beside the old hole (now plugged with my broken bit) and it drilled out an alternate hole right beside the old one. Well... same amount of gas will go through, so no harm in trying this out in the stove, I reasoned.
In hindsight, I think I should have left one or two holes undrilled to verify flame size, and only drilled out as many as were needed to achieve the flame I wanted. But in the end I was satisfied with the appearance of drilling them all out with the #61 drill bit. Photo below.
So what I was missing with this stove was the first piece of direct venting, the collar that allows you to attach onto the direct venting. I tried using a loose fitting alternative just for testing and the results were disappointing, a limpid set of gas flames came out of only the front set of holes in the newly cleaned burner with a fresh gasket, but no flames out of the rear sets of holes. But here is the deal, your venting does affect how much flame comes out of the burner. My stove had a restrictor plate in the flue opening, which is used when you have a very tall chimney heading up through a roof. The taller chimney exerts a much stronger draw than the short one, but I had only a short piece of direct venting for testing. With the loose fitting vent collar, we were not getting hardly any draw up through the stove. The restrictor is just a flat metal plate with a smaller size of hole drilled in it, that narrows the opening so less gas and air can go up a very tall vent. It is removed for the shorter flu application where the venting goes up a few feet and turns to go out through the wall.
I took my restrictor plate out (3 phillips head screws hold it in) and retrofitted a vent adapter that really did allow a proper, tight, fit onto the direct vent pipe above, which ended just below the 8 foot high ceiling in the shop, so fairly short. I relit the stove. This time the additional upward draft created by the venting caused the flames to appear in all the holes of the burner, and they were just in the size range I expected to see for a gas fireplace. I took a quick photo without any logs in there, and this was on the low flame setting of the gas valve. The high flame setting was only a small amount larger. I may opt to change the air shutter (in the air intake pipe below the gas burner), to reduce yellow flame a little, but this is the initial shot with the air shutter set about half way open.
I want to comment about alternative parts. I wanted to replace both my gas valve and my pilot assembly with this old stove. I found the natural gas valve at fire-parts.com and ordered
Dexen / Robertshaw Millivolt Valve Quick Drop 30% Turndown (Natural Gas)
The sku number that you can search to bring it up there isFP2007
It cost $94. in March of 2024 on this website.
I also wanted to replace the pilot assembly where your thermocouple and gas pilot flame reside, and ran into the inevitable, No Longer Available thing... but I discovered that there is an alternative one that can be used with excellent results. This was the Heat N Glo Heatilator Quadra Fire Natural Gas Pilot 485-510A 4021-736
It comes with a new natural gas pilot orifice sized correctly for Natural gas. Mine cost about 50 bucks on ebay, but I notice it is available on amazon.
I'll try to attach a few photos to help educate any other person considering doing their own conversion. For sake of liability, I must say that I don't recommend doing this as a homeowner, or as an unlicensed person. The info may be helpful if you can work with someone who is licensed to make this conversion. Today I hope to start up the stove and leave it running long enough to verify if my fan motor will kick on and verify that it is not too noisy.
