Hydronic heating

RMA

How many BTU's can I get off 1/2" supply and returns

Josh_10

2 Magic words... "it depends."

If you keep the velocity below the recommended 4 feet per second you can get 3.1 gallons per minute of flow. If you go with the standard 20 degree delta on temperature differential you can transfer 31,000 BTU. If you go with a 50 degree delta on temperature you can transfer 77,500 BTU.

Of course if you are willing to increase the velocity to something crazy like 8 feet per second and want to pump the system with a 747 engine you can do 6.3 gallons per minute and transfer 157,500 BTU at a 50 degree delta.

RMA

that's plenty
I'm using a mainifold distribution system.
three supplies up to three base boards, and three returns back
about 6 to 8,000 each

Bill Julian

NO FLOW!! BASEBOARD

Connected another zone today (7 now in all) to a Burnham boiler hot water gas. Basement zone has 2 u shaped loops but water flowing with fast fill used.
When a call for heat the feed or return does not get hot..Can't figure it. Do I use circ with relay or tap into the top of the U shaped loops with a tee and bleeder?

Unknown

Bill, you need

Bill, you need to repost this on its own thread...
Did you use TWO divertor tees for those radiators below the main?

Bill Julian

NO HEAT FLOW

Got your post I left another post. No I did not use diverter tees, MUST I? The main is 11/4 copper I haven't seen a diverter tee 11/4 have you?

Why a diverter tee anyway? Why not a pump on the branch for the basement zone?
You must be saying that the water is racing by the basement tee (feed) and ignoring passage. Would an 11/4 ball valve installed after the 11/4 X 3/4 tee (feed) be useful to divert some of the water into the basement branch work robbing the rest of the house?

Thanks