Which comes first, Storage or Load?

[ewdudley]

My slab runs are 3/4" and are quite small--only 200 feet each--I figured, for the amount they are run--which is mainly to keep the slabs above 40º at the very least--the 007 would be sufficient. Since it is on it's way we will find out!

Yeah, you're right the 007 is very likely a better choice. I was speculating 300 ft loops of 1/2".

A dry 40 degree floor would be awfully nice on a winter day.

 

[hobbyheater]

Heat Farmer

I don't know if these diagrams will help or not. These drawings are 30 yrs. old.

Allan

 

[mwk1000]

I just used a T at the output from the HX, One side is the load/house the other is the top of the tank. If the boiler is running and all is hot the HX tank pump is active and HOT water is coming out the HX. If load is called for then the HX water will be pulled by the load pump directly. If no heat is called for the valves are shut and the only route for the water is into the tank top. If the boiler is cold the HX has no flow and the house pump pulls water from the same line that was feeding the tank is now suppling the load. Solved the who gets heat first problem for me since when my system is cold the Furnace is on full time and the tank is well mixed so the idea that I will be able to get hot water from the top of storage did not pan out.

I liked the idea because the number of components was small, 1 HX 2 pumps and I am cheap. I have an external flat plate HX that forms a very simple boiler loop that is all the the boiler feeds, into the HX and back. So I could run antifreeze and a small volume of water the other side is un-pressurized and an open tank system.