On Wed, 25 Dec 2013 08:48:45 -0800 (PST), "
wrote:

On Thursday, December 19, 2013 1:17:00 AM UTC-6, Gz wrote:
Today's furnace specify btu. Is that input or output ? Greg

I haven't pursued getting a "modern" furnace because I have neighbors who have put in newer furnaces and have had all sorts of problems with them. As an electrical engineer, I love to try new technology, but I have to say that I will keep this furnace for as long as it holds out since there is nothing electronic to go wrong when there is are nearby lightning strikes or power surges, both of which have taken out neighbors furnaces more than once.

I'd have though that an electrical engineer would have the solution
for that.