Looking for review of my Radiant Heat Schematic

billybaru13

A little background: I've researched extensively on radiant heating systems in this forum and have taken inspiration from various discussions. The goal is to design an efficient and reliable system for my shop.

I've attached my schematic for your review, and I have a few specific questions:

1. Are there any glaring issues or potential improvements that you can spot in my design?
   
2. Are there any components or features you would recommend adding or modifying?
   
3. Based on your experience, do you foresee any challenges or compatibility concerns with this setup?
   

I truly value the insights and wisdom of this community, and I'm eager to ensure that my radiant heating system will function optimally once implemented.

GGross

given the boiler and the emitters that you are using I would say the mixing valve is unnecessary

Alan (California Radiant) Forbes

Looks good. Don't forget a fill valve unless you want to fill manually.

Just one zone? What model system pump will you use? There's hardly any pressure drop. Maybe 2 feet of head, flowing 4 gpm. A Taco 006 or even a Taco 003.

hot_rod

A simple one temperature option

Hydromatt

I agree with all the above… Delete the mixing valve, add backflow preventer and fill valve for trouble free ops. 

If im not mistaken, That model is a Combi boiler, are you planning to use it for DHW also? Otherwise a standard boiler would do.

billybaru13

Updated schematic and notes.

hot_rod

The #7, air purger goes in the red/ hot supply, where you show it.

#10 the expansion and fill should be below pump#1.
Always pump away from the tank connection into the system. If you plan on ECM circs now or later, add a mag separator on the blue boiler piping somewhere.

A hydraulic separator may not be much more $$ and you get 4 functions in one device.

billybaru13

So something like this...

https://www.supplyhouse.com/Caleffi-549596A-SEP4-1-Sweat-Union-4-in-1-Air-Dirt-Hydro-Magnet-Hydraulic-Separator

I like the idea of ECM circulators. Not super familiar with them, but the adjustability seems like a good feature to have. Could probably really dial in the delta T of the slab

billybaru13

And something like this for the pumps

https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Taco-006E3-Product-Overview.pdf

hot_rod

billybaru13 said:

And something like this for the pumps https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Taco-006E3-Product-Overview.pdf

That is a domestic water circ, typically. So it will be more $$ then a cast iron body.
if you like that color look at the 007e

billybaru13

It looks like I can use my boiler to drive both pumps, and just wire the thermostat to the DHW thermostat (143 in the diagram)

billybaru13

In my original schematic I have the "green" layout. The red layout seems to make more sense to me for filling the system the 1st time.

Thoughts? Does it matter? Am I splitting hairs?

hot_rod

I don't like to see expansion tanks straight down from any sep, although you don't need that additional air sep
Because any debris that come out in the sep falls down on top of the diaphragm in the expansion tanks. Either use a tee and offset the tank connection, or the red option.

And of course I would use a Caleffi 573 AutoFill assembly. It fills at 5 gpm without needing to trip any levers.

billybaru13

Here is the finished product. Its been running for about a week now. All the air bled out after 2-3 days and it is working flawlessly. The only pain was when I went to turn the boiler on for the 1st time it flashed a bunch of error codes at me. Turns out it was too cold to turn on (25F). Popped a space heater in it for a couple hours and it fired right up.

Thanks for all the help guys. You gave me the confidence to undertake this project myself.

Alan (California Radiant) Forbes

Nicely done! Air purging gets real easy when you add a ball valve and drain on the return from the manifold.