Where to Install Circulators

AHS 260 installed in garage.
It's going to be roughly 125' from the boiler to the manifolds and indirect water heater.
I'm running 1.25" pex al pex from the garage to the house.
I've read conflicting information about where to place the circulators. Made a simple diagram of the system. What recommendations do you all have, thanks. Eventually the garage with be heated along with a hot water for a bathroom.
Heating with cast iron radiators.

Where ever you locate the expansion tank, scoop/vent and water fill combo is where...then you "pump away" from that whole combo.

I would locate the circ so that it was pushing toward which ever is higher the garage, or the house. And then locate the tank/scoop assy. just upstream of the pump.

jrv8984 wrote:AHS 260 installed in garage.
It's going to be roughly 125' from the boiler to the manifolds and indirect water heater.
I'm running 1.25" pex al pex from the garage to the house.

I've read conflicting information about where to place the circulators. Made a simple diagram of the system. What recommendations do you all have, thanks. Eventually the garage with be heated along with a hot water for a bathroom.
Heating with cast iron radiators.

============================================================================

Hello jrv8984,

The first thing I would suggest is that you order two paperback books, The first being Classic Hydronics and the second paperback book is "Pumping Away".

The paperbacks can be purchased through http://www.dansbooks.com, Barnes and Noble or Amazon.

These books were written by Dan Holohan a gentleman who has gained an extensive amount of experience from working in the plumbing and heating industry as a plumbers helper, a technical and sales representative for a wholesaler selling B+G and products and also as a plumbing and heating troubleshooter on Long Island for many years.

Mr. Holohan writes all his books on plumbing and heating from the laypersons perspective and he explains everything down to the smallest detail about steam heat, gravity hot water heating, hot water circulation heating, forced air heating and air conditioning works in his books he speaks from the point of massive experience working in the plumbing field and takes the time and effort to explain everything so both an experienced plumber and a home owner understands how a heating system of any type works.

I would suggest that you order these paperback books first and then decide whether you want to mount the circulator in the garage on the boiler or in the basement if you have one as many folks install thier circulators and controls in the the living space to protect them from freezing/bursting damage.

You also need to have a dump zone with a separate circulator or a dump zone valve in case the boiler overheats unless you intend to use the home heating loop as a dump zone. This is also explained in the two books I mentioned as well.

I had lots of questions when I started looking at coal stokers 8 plus years ago and everyone here has helped me with my system. ALL I need is really cold weather now.

Are you sure you want to put the two manifolds in parallel with each other and separate the returns?

If you run them in series and use closely spaced tees for the supply and return lines of each zone, the system will balance quite nicely and be easy to handle high and low demand times of all the zones.

It can also help your boiler maintain a steady temp, with a constantly circulating primary loop.

If you are going to have a circulator pump in each zone, it gets even easier. One Tstat for each zone/pump, the closely spaced Tees takes care of the rest.

As for the primary pump placement, with the above system, I prefer to pump INTO the largest resistance. If you use a continuous primary loop, your Boiler is the biggest resistance and you can put your pump at your boiler to pump INTO the boiler. This is the method in a number of Installation Manuals for boilers.

The individual zone circulators + closely spaced tees would take care of balancing its own zone with the rest of the system.

How many radiators are you expecting to have on each zone?

Split Tee design for supply and return lines of each zone, with a balancing valve (ball valve), one on each side to account for different resistance of the radiators, etc. You can even mix radiators and baseboard, or whatever in this setup, it doesn't care

Split Tees will help keep more of your radiant elements (rads/bb) at the system supply temperature, thereby improving (sometimes significantly) how well they provide heat to the zone.

If not....

125' plus radiators could be a SIGNIFICANT resistance. Balancing the separate manifolds and individual zones could be a bit of a challenge without zone circulators and such.

FWIW, "pumping away" is pitched as the "ideal" way to plumb heating, but a lot of things have to be right and all has to match up. If done right, it's good. The way I mentioned above is pretty forgiving- both of mistakes and compromises due to location, walls, pipes, etc.

Edit: Here's a link to my system, using closely spaced Tees and backup oil boiler. CoalisCoolxWarm @ LL AA-220 Max Draft Burn With Power Vent Please Help!

Another link that shows my zones and closely spaced tees.

What to Do With an Afternoon and a Few Hundred Bucks?

Do yourself a favor and use flanges with integrated valves. You can add/service/whatever in a zone, including a pump or piping, while your system is "hot" and running

I was planning on using caleffi manifolds. all the radiators have been disconnected because I am restoring the house, so they will all be reconnected with 3/4 pex al pex. I'll only be using a manifold with 5 ports at present. As the house gets renovated and additions removed and rebuilt I may end up having 3 manifolds. So in my mind I would have 3 zones, one for each block of the house.

There will be 5 radiators to start, 15-20 when the house is finished.

Planning on using TRV's on all the radiators, so I figure I only need a circulator on each manifold, and one on the indirect hot water heater.

The boiler in the garage will be higher than the manifolds and hot water heater in the basement.

Do you have a pic of this flange with integrated valves?

jrv8984 wrote:Do you have a pic of this flange with integrated valves?

This system needs to be as simple as possible, what that means is limiting devices that use electronics other than the circulators, hence the TRV's.

Thanks, McGeiver, for posting the valve. Notice he posted the one with the SWIVEL FLANGE, which allows you to change the orientation of your pumps during installation. I have an odd position pump because I didn't have one of those

Why do you want to avoid electronics? Thermostats and zone controllers are quite simple to do.

For example, the Taco 504 4-zone controller that I and some others use has ONE 120V input, a simple 2-screw input for each thermostat, and sends ONE TT ("thermostat is calling for heat") signal to the boiler. The boiler works like it only has one thermostat/zone on it, it doesn't care about all the other stuff.

The 504 also has a Priority switch that you can turn on or off, usually for indirect hot water heater. And you can daisy chain them with a single piece of 2-wire thermostat wire. Each pump gets its own electrical connection, clearly labeled.

Let me find a pic.

Here's the wiring for the Taco 504-EXP (4 zone)
At the bottom you can see the black and white power wires. Far right is single 120v input. Each of the others is a zone pump that gets its power. Simple

You can ask as many questions as you like. Any of us will give you pics of our wiring/setup as you need it.

We share information and help each other learn about their systems. We are a "warm" bunch, LOL.

Simpler is often times more durable, and more satisfying depending on what your doing.

That being said, are you saying I could use the taco 504 to control the circulators for my 3 proposed zones and use the 4th zone for the indirect water heater along with the priority switch?

What controls the circulator at the boiler?

Also, does anyone know who makes the most efficient circulators?

jrv8984 wrote:That being said, are you saying I could use the taco 504 to control the circulators for my 3 proposed zones and use the 4th zone for the indirect water heater along with the priority switch?

That's what I do now.

What controls the circulator at the boiler?

The triple aquastat. That is its job by design.

Also, does anyone know who makes the most efficient circulators?

Can't answer that one, but know that a Taco 007 (a very popular circulator) uses about 0.7- 0.8 amps when running. Yes, that is less than one amp

Grab a cup of coffee tonight or tomorrow and read the thread I posted above under "Another link that shows my zones and closely spaced tees."

It shows my build and installation. See if any of it helps you decide what you want to do.

There is another thread where I posted ALL the wiring at the boiler, fully labeled down to the color of the wires, to help another person with their boiler last year.

Others have done similar things, too. You have definitely come to the "right place" for information about coal boilers

FYI. I am plumbed for 12 zones, wired up to 8 for now- using 2 of those Taco 504 controllers. When I added the second one, I cut off about 24" of thermostat wire, connected the "master" of one to the "slave" of the other and made sure the second one was set to "slave." Done. Add the thermostats and pumps at will. I also had to add the 120v power connection (far right in the pic), just like the first one.