Counter-flow piping ?

bill nye_3

What was the supposed advantage of piping through the boiler "backwards " ? pumping out of the return towards the system and returning from the system to what we would normally consider the supply. This was done in my boss' house in the 1970's and he asked me why his Dad had it done this way. Was it supposed to be quieter ? I have seen it a few times .

Gordan

Some kind of "self-tempering" (boiler protection without bypass) is the only thing that comes to mind, and even that's questionable.

bob_46

In the 60's there were some vertical fire-tube steel boilers on the market that pumped out of the bottom and had the pump on the supply. Triad and Edwards come to mind . They worked great, zero air problems. I'll bet the designers of these boilers knew Gil Carlson. Because of their success I believe fitters figured that this way of piping might work well with cast iron boilers and experimented, with mixed results. Dr. Johannes Mueller the head of boiler design at Weil-McLain wrote a booklet Normal Flow vs Reverse Flow in Cast Iron Boilers . He explains in detail why boilers should be piped with the flow in the direction the boiler designer intended. He acknowledges working with Mr. Carlson from B&G.

Tinman

That Triad steel boiler you mention is the very first boiler I ever replaced, back in '82. I'll never forget that day. It was a nightmare.

Mad Dog_2

Wow Bill Nye....blast from the past. Please give me a call or an email when you can go get caught up Plumbing3c@gmail.com. 516 322 28 81 mad dog

bill nye_3

I worked for an oil company that was founded in 1929. They installed Weil-McLain and a few were done like this. They used a subcontractor the Konokowski Bros. who had mad piping skills , legends. They did the ones that I had seen . I also saw some Edwards boilers when I worked with my Dad. I asked the two best plumbers in town about counter-flo piping today. They both agreed that they had seen it , never done it, and were not sure of the reason.

Mad Dog , never got into the new wall . Been super -busy. This was the only place I knew I could get an answer.

EBEBRATT-Ed

I have seen jobs in schools done in the 60s with H B Smith header type boilers, 640s, 650s,450s etc where you had the two "return drum" headers at the bottom and the "supply " header on top. That's the normal configuration.

I have seen them pump into one return header at the back of the boiler and take the supply from the other return but at the front of the boiler, nothing connected to the supply header on top. This way the water goes in the bottom , over the top and out the other return so the water crosses the boiler in two directions. Apparently for whatever reason it didn't work out so well because they don't do it anymore

bill nye_3

I spoke with the retired man who worked on this system when it was new. He actually took the job over from another man who retired. The reason was for quiet operation . If the boiler temp. stacked the idea was the hot water would cause expansion noise in the piping and fin tube. I think in a residential boiler , the water coming out of the return is going to be damn near as hot ? Much ado about nothing . I was looking for deep scientific or philosophical reasoning for this , oh well. Just be careful when you change the circ. pump , they are all upside down.

bill nye_3

p.s. Outdoor reset and constant circulation would have been much better