I have to replace my furnace. It is a very old oil burner and I want to change to gas. I have a gas water heater. The gas line coming in is 3/4" and I am getting conflicting reports whether that line is big enough to convert to gas. Can anybody give me an answer?
Thanks,
Mike

Are you on natural gas or propane? What size water heater do you have (btu) and what size furnace will be installed?

Are you on natural gas or propane?

Natural gas.

Are you on natural gas or propane? What size water heater do you have (btu) and what size furnace will be installed?

Sorry I didn't see the other questions you asked. We have natural gas. The water heater is 50 gallons and I believe they are talking about 240,000 BTU burner.
Thanks,
Mike

If the furnace is actually going to be 240,000 (thats really huge for a residential dwelling, so recheck and get back to me). If the furnace is actually that big, you will certainly need a one inch supply from the meter. Off the main you will supply the water heater with 1/2" and the furnace would most likely 3/4. Is it a big job to run the new 1" line?

Hi Mike,

I agree with MGD77 in terms of minimum sizing here, but we really need to know the distance from your gas meter to your new boiler. Here, measure the distance from the meter in terms of how the pipe would be run, 90s and all to where the new boiler will be placed including the drop down from the ceiling to the boiler gas valve (approximate). Present that distance AND the distance from the meter to the farthest appliance being served by natural gas (water heater or boiler) and we should be able to finalize an answer for you, OK?

Finally, are you planning on adding a gas dryer, a gas stove, a gas grill, or a gas firelog in the future? If so, we should include that in the pipe sizing for you so you can be sure you only need to do this one last time!

Back to you...

Mark

What is the size of the gas pipe coming from the other side of the meter? If it is 3/4 too you are likely sunk