Mr. Hot Rod

cutter

There was a hydraulic separator question earlier but I have another. I installed the system design that is in idronics #10 page 29 figure 6-14. I am most likely over sized on the separator right now but I will be adding heat to my garage and two more small rooms. The generously sized headers I put in are most likely oversized also. I have no complaint's with how the system works. The only compliant I have is I was limited on room for the installation. Here is the question, What does the hydraulic separator do, what is it's purpose?

hot_rod

I can't quite see the sep clearly but it looks like a Sep 4. If so it is a great micro bubble air separator up top. At the bottom it is a small particle dirt separator, down to a 5 micron particle. If may have a magnetic band also? If so it pulls magnetite out of old iron systems.
As for the 4th function it hydraulically separates them various components tired to it.
Looks like two boilers fee into it? A couple speedy headers on the outlet size with zone valves?
It does need to have circulators on both sides.
Usually right at the top right would be the distribution side circulator. Each boiler would also have a circ.

Distribution side could also have zone circs instead of zone valves.

cutter

It is plumbed just like the book. Each boiler has a pump that pulls water towards the boiler. They are just not in the picture, wrong camera angle, and too low in the picture.


On the distribution side there is a second smaller header in front of the upper main header. another pump pulls water from the upper main header and pushes the water through the zone valves to the zones calling for heat.

I have dumped water from the separator several times after taking the magnetic band off, have never gotten any significant amount of dirt or trash, pretty much clean water.

The distribution side does not have the room for circulators on each zone. One zone is too small for a circulator.

On top of that upper distribution header are three ports, one for the garage unit heater and two more for a couple of rooms in a add on.

hot_rod

Getting all that together with threaded pipe must have been a feat!

cutter

Getting the pipe together took a while. There is only one plumbing wholesaler who would talk to me. I bought the pipe one or two pieces at a time. all U.S. pipe.

You explained all the features of the hydraulic separator above. But why is the water able to go from the top of the separator to the lower portion of the separator and back to the boiler return. If a zone wants heat the zone pump pulls water through the top of the separator and to the zone or zones, then back to the lower header and circulates through the separator until the water in the boiler water is hot enough to open the boiler protection valve, then the water returns to the boiler. I have forgotten how the caleffi ZVR 104 controller works other than the controller is powered up when the boiler water gets hot and the boiler pump comes on starts circulating water, at the same time the zone pump comes on and circulates water through the separator and to the zones. No hot water or very little goes through the zones until the boiler protection valve gets hot enough and opens up. Did I just explain to myself why the Hydraulic separator is built like it is or is there another reason?

hot_rod

Think of a hydraulic separator as just a wide spot in the road.
It is just a pipe of a large enough dimension to allow different and multiple flows to move through.

It's like 8 lanes of the 405 in California. That highways allows multiple direction of travel, many different speeds, vehicles constantly entering and exiting, all moving happily along together. Most times:)

The boiler protection valve never closes both ports. 100% goes back to the boiler when cold, as it warms that valve allows flow to the system at the rate the boiler can supply it.
Another car analogy, think of it as slipping the clutch to get a heavy load moving from a stop.

So heat energy is always available to system either the boiler or both boiler and distribution. The boiler protection valve allows this to happen at a rate the boiler is comfortable with.

The ZVC is just a bunch of switches inside a box. 24V is produced to power the t-stats and zone valves. The zone valves "tell" the boiler and circulator to energize when heat is needed.

The relay switches electricity on and off, the zone valves switch water flow on and off.

cutter

Thanks for the information, with what I learned in the Caleffi trade journals I got the system put in and the return water is 20 degrees cooler than the supply water, within a couple of degrees, sometimes. Everything seems to be working like it is suppose to, so no complaint's there. I kind of like how it is and has been working. You have given me tips and help in the past also, thanks for that.

hot_rod

glad to hear all is well.