Diverter Tee's

Hilly

I cannot find in any literature how to determine the spacing of diverter tees. I know Dan has said. 2 for downfeed, 1 for 1 floor up and 1 for 2 floor up with increased riser sizes. Most other literature agrees but everyone always seems to say "2 monoflo tees may be require if the resistance is too great on the branch assembly" So I found a heater that doesn't work in a house tonight. I figure freeze-up initially but it wasn't. The monoflo on the return is installed backwards. He had it re-piped into 3 monoflo zones when got the new boiler 5 years ago. So... since I am going to fix it I want to make it right. The heater is 5' wide and it's a cast iron stand up. The risers are just on the floor above (so about 10" height gain) and the lengths are approx 10' and 15'. So I guess my question is how can I know what really constitutes "long branch pipes" and "higher flow resistance". The monoflo trunk is 3/4" with 1/2" risers.

Ironman

As Dan always says "think like water". It takes the path of least resistance. Which way would you go if you were water?

It may sound simple, but it works.

The Tees should be a MINIMUM distance apart equal to the width of the radiator. If the risers look excessive, place the Tees farther apart or use two monoflo Tees.

A cast iron rad has almost no flow resistance, but the risers...

Hilly

That's the thing, what's excessive? 5,10,20,50'?
It is just a number.

Ironman

Horizontal or virtical? You can get by with more length in the risers if they're vertical. I know the resistance is the same either way, but the lower buoyancy of heated water naturally goes upward inducing some more flow. I've gone 2 stories to convectors with one monoflo Tee.

If in doubt, use two.

Hilly

It's horizontal then vertical 10"