Heating, Air Conditioning, Fridge, HVAC/gas conversion


Joseph,  I am going to be coverting my furnace to nat. gas from propane.  I have the orfices I found in a bag hanging on the wall next to the furnace. I didn't find a spring under the screw on top of the gas valve.  I did notice that there is a inlet pressure tap and outlet pressure tap on the sides of the valve.  Is this an adjustble valve as I know I have to go from 11" to 3
1/2" water column.I'm not sure about what to do to the gas valve for this coversion? I would appreciate any info you can give me.
The furnace is an American Standard Freedom 90 Two Stage.  It is about 20 years old.  Thanks alot, Rick


If the orifices your talking about are several brass screw in plugs with a orifice that go on the burner main tube, that would be a start,( remove the propane rated ones for the natural ) Hopefully they are the correct size orifice number for your furnace. the other parts are a very fine spring(s) usually color coded, propane spring(s) may be yellow, while natural may be red ( or vise versa ) and possible a ball bearing. It may be more safer for you to buy the natural gas valve instated of converting back to natural. Where is the instructions for the conversion??.it should show you how to convert it, and where everything goes. Yes 3.5" is typical for natural gas depending on altitude. most cases around 3.5" will work at the outlet pressure tap.Inlet pressure tap is your gas coming into the furnace.

Heating, Air Conditioning, Fridge, HVAC

All Answers

Answers by Expert:

Ask Experts




40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

©2017 About.com. All rights reserved.

[an error occurred while processing this directive]