Michael Mortara
06-20-2008, 09:40 PM
Well here is the three month review of our recuperater retrofit.
We have been running a SiC furnace with a 200# free standing pot for almost 8 years, until February when we changed over to gas fired with a Jenkins Re-Hugh-perator. Our shop built furnace was a great unit that gave us not one bit of trouble in the last six years. The trouble began when our electricity hit 40 cents/kw here on the Big Island. Our bill jumped from $1800 a month to $2900 in a matter of a few years, with no end in sight. Our furnace used 5000kw/month. Ouch.
With the economy headded into the toilet we really had to stretch to cut costs in the studio, and though messing with the furnace was the last thing I wanted to do, we were running out of options. Some of the things that worried me about switching over to gas were glass quality, maitenence, dependability, noise and rate of return. Still, Hugh lives just an hour and a half from me, and his son Evan has worked in our studio for the last five years so I had no worries that any problems that came up would be adressed.
So we went off to the show in Philly, came back with a bunch of orders, and turned off the furnace (had a two year old EC pot that needed changing any way) and went to work.
That entailed cutting a 8" x 14" hole in the refractory wall (not fun)
and setting up for the burner block and heat exchanger (welding supports)
adding an air compressor and spare air storage tanks. Plumbing new air and gas lines. All told including everything it cost us about $4500 and took about a week of hard work.
Hugh came by with the parts, went back home to start over, came back again a few days later, we set it up and turned it on. It crawled up to temp slowly, I started stressing, frantic call brings Hugh back, he twiddles something, the furnace roars to life, we sit back and let it do its thing as it gets up to temp.
It gets up and I start dialing back the gas. Down it goes, and goes, and goes. Next day with a rough idea of settings (gas, air, damper) we start filling the furnace for the first charge.
Three months later this is what I know.
1. I am saving $1000.00 a month on my fuel bill.
2. The quality of the glass (system 96) is far better than it ever was with the old furnace,though it is a bit stiffer.
3. This system in more hands on, but not excessively so.
My current idle setting for the gas is 6 4/10" of water through a #44 jet.
The most suprising result was the change in the glass quality, we were having cords and seeds with the old furnace that never completely went away, now we have really clean glass, which I atribute to better convection. Bottom line is that it works and works in a production studio setting where glass quality is really important.
We have been running a SiC furnace with a 200# free standing pot for almost 8 years, until February when we changed over to gas fired with a Jenkins Re-Hugh-perator. Our shop built furnace was a great unit that gave us not one bit of trouble in the last six years. The trouble began when our electricity hit 40 cents/kw here on the Big Island. Our bill jumped from $1800 a month to $2900 in a matter of a few years, with no end in sight. Our furnace used 5000kw/month. Ouch.
With the economy headded into the toilet we really had to stretch to cut costs in the studio, and though messing with the furnace was the last thing I wanted to do, we were running out of options. Some of the things that worried me about switching over to gas were glass quality, maitenence, dependability, noise and rate of return. Still, Hugh lives just an hour and a half from me, and his son Evan has worked in our studio for the last five years so I had no worries that any problems that came up would be adressed.
So we went off to the show in Philly, came back with a bunch of orders, and turned off the furnace (had a two year old EC pot that needed changing any way) and went to work.
That entailed cutting a 8" x 14" hole in the refractory wall (not fun)
and setting up for the burner block and heat exchanger (welding supports)
adding an air compressor and spare air storage tanks. Plumbing new air and gas lines. All told including everything it cost us about $4500 and took about a week of hard work.
Hugh came by with the parts, went back home to start over, came back again a few days later, we set it up and turned it on. It crawled up to temp slowly, I started stressing, frantic call brings Hugh back, he twiddles something, the furnace roars to life, we sit back and let it do its thing as it gets up to temp.
It gets up and I start dialing back the gas. Down it goes, and goes, and goes. Next day with a rough idea of settings (gas, air, damper) we start filling the furnace for the first charge.
Three months later this is what I know.
1. I am saving $1000.00 a month on my fuel bill.
2. The quality of the glass (system 96) is far better than it ever was with the old furnace,though it is a bit stiffer.
3. This system in more hands on, but not excessively so.
My current idle setting for the gas is 6 4/10" of water through a #44 jet.
The most suprising result was the change in the glass quality, we were having cords and seeds with the old furnace that never completely went away, now we have really clean glass, which I atribute to better convection. Bottom line is that it works and works in a production studio setting where glass quality is really important.