hydronic heat for the barn - part 7

 

In order to keep the cost to minimum I carefully planned to buy only one large diameter copper pipe. The installation requires 1 1/4" as well as 1" diameter pipes as the boiler ports are the former while the manifolds are the latter. But I have a 5-foot piece of 1" left over from my previous boiler installation. I designed my installation so I only need to buy one 10-foot piece of 1 1/4" pipe.

The other self-imposed constraint is to use up the pair of 1" diameter pump valve flanges I already have. Reaching this goal requires carefully planning of the layout, as well as avoiding cutting mistakes. If accomplished this will also result in the best performance with the least flow restriction as the use of the smaller diameter pipe will be minimized.

a good bowl of little clay pot rice

While awaiting for the parts to arrive from the East Coast I made some small progress in going as far as I could without risking waste. I measured and cut a few more short pipe stubs and dry fitted them.

I prepared the long pipe for the other pump flange, as well as the 1" short copper pipe connecting to the return manifold, both with the 1 1/4" to 1" reducer. This is as far as I could take the work until the few 1 1/4" 90 ells show up.

I also made sure I have the needed 1/2" fittings

The 20 gallons of automotive glycol arrived via Fed Ex and I am quite impressed with Walmart. They were shipped from Eastern Oregon.

I feel sorry for the Fed Ex driver having to unload them

While soldering the isolation ball valve with drain I notice the drain valve passage was wrong for my intended purpose. When the isolation ball valve is close the drain path is towards the sweat end of the valve instead of the union where it connects to the boiler. I didn't give it much thought at the time as there is nothing I could do.

Only later when I realized the handle could be reversed by flipping it 180 degrees. This change allows the big ball valve to rotate 180 degrees also, and making the drain path towards the union side of the valve. The purpose of the two isolation valves are to allow orderly draining of the boiler, and then its removal from the wall.

the note that the handle is reversible gives a noob no hint as to the purpose until you really think about how the ball inside is made

right now the drain path is towards the sweat (bottom) side port 

by reversing the handle of the right side valve the drain path is reversed to the union (top) side port

only the handle is too long and could not be fulling open the valve in normal operating orientation; I just need to remove the yellow plastic sleeve and cut it shorter

So far I only have a vague notion with all the features of the manifold set. I know one manifold has individual metering valves that is intended for the return path, and the other has individual flow meters that is intended for the supply path. I would later realize the each of the flow gauge can be adjusted for flow as well. So why two redundant provisions for flow adjustment?

It turns out the design allows the metering valves on the supply manifold to be replaced with what they call electric actuators for zone control. To do that you just remove the metering valve, and replace it with an electric actuator. There are a basic 2 wire actuator, and a 4 wire actuator for use with a zone thermostat directly without the need of a zone controller.

the metering valve knob removed

the valve is spring loaded to open

this is how it the valve knob could be replaced with an actuator

this is a 2-wire basic electric actuator

this is how the actuator works - on or off

once you pop off the red locking collar the flow meter could adjust the flow - hence the individual balance of the loop

the flow valve fully raised

When I set out to design the hydronic heating I planned to keep it very simple as the barn is one giant open space. I wanted to keep the two right most bays' floor area relatively warmer by setting the balancing bias to that two bays. I also want the back walls of the barn to be warmer than the garage door side as that is the side most work get done.

The discovery of the actuators open up another dimension of control with very little added cost and complexity. I plan to have a bank of 8 switches to control the actuators. There will still be one thermostat that control the boiler based upon the air and slab temperature. I would be the other walking human thermostat with fuzzy logic that control the on/off of each loop. How elegant is that?

Hydronic heating has advance greatly in the last decade, largely the innovations in Europe. Only if I have less projects designing and building my own network controller with multiple remote thermostat would be a lot of fun. However, I don't see that happen as I have endless projects and improvement projects planned. For the hydronic system I would keep it very simple for now.

this switch bank should do the job nicely for loop control

I order a ten pack of the cheapest actuators from Aliexpress as the ten cost nearly the same if you buy one from radiant floor heat suppliers in the US!