Hydronic Radiant Heat System Piping Size

[like2wheel]

I already have five loops of 1/2” pex in my floor (1400 sqft), and I have been accumulating pieces for my Navien NHB110 boiler plumbing. I have several 3/4” sweat isolation flanges for the pumps (auction win), but when looking for a purge tee, I see the smallest available is 1 inch by 3/4 inch. Does that mean the primary loop needs to be at least 1 inch? Secondary loop?
.
Any input is appreciated.

 

[fitter30]

How many feet of pex ( oxygen barrier)and loop lengths? Piping using primary/ secondary?

 

[like2wheel]

Each loop has approx 275’ of oxygen barrier pex, & as I learned here, I will be using a primary/secondary loop

 

[Firebrick43]

https://www.supplyhouse.com/Webstone-48613-3-4-IPS-Purge-Fill-Full-Port-Forged-Brass-Ball-Valve

3/4 is available.

Are you looking for sweat copper, threaded as above, or something else?

Question is though, why are you necking you boilers output and return down from 1" to 3/4"?

 

[like2wheel]

https://www.supplyhouse.com/Webstone-48613-3-4-IPS-Purge-Fill-Full-Port-Forged-Brass-Ball-Valve

3/4 is available.

Are you looking for sweat copper, threaded as above, or something else?

Question is though, why are you necking you boilers output and return down from 1" to 3/4"?

I guess I didn’t realize I was. Last summer I bought a T-H3M-DV–N 100 Takagi. That has three-quarter inch water piping. Then this fall there was an auction for a brand new Navien, so I thought I’d be better to use that. Didn’t realize that uses 1”.
So I have some other brass that I had accumulated that is also three-quarter inch. I’m guessing I should abandon that and pipe it 1 inch? Does that mean the secondary should be 1 inch also?
Here is a picture of the type of purge valve I was looking for. I was planning to use it to plumb my closely spaced tee’s.

 

[fitter30]

275' loop x 32 btu's per ft 8800 btu's per loop
9' + 2' = 11' for head need to know how many loops for gpm and pump size
Recommend a micro bubbler for air removal. Glycol? Use only boiler / chilled water type. Minimum 30% ( for the inhibitor package) can set up for two different protection. For hard freeze or slush. Slush will not freeze hard and will not break piping. Wouldn't recommend a permanent fill line. With a permanent fill if there is a leak and it's not detected glycol gets diluted and with a power failure system freeze. A cheap drill motor pump can fill the system and add solution if needed. Low water cut off for protection.

 

[like2wheel]

275' loop x 32 btu's per ft 8800 btu's per loop
9' + 2' = 11' for head need to know how many loops for gpm and pump size

5 loops, my manual recommends a taco 0015-MSF3-IFC or a Grundfos UPS15-58 for what looks like the primary loop.

I do have a taco 007, and also a 0010 (more auction booty), wondering if either of those is suitable for the secondary pump.

 

[fitter30]

5 loops, my manual recommends a taco 0015-MSF3-IFC or a Grundfos UPS15-58 for what looks like the primary loop.

I do have a taco 007, and also a 0010 (more auction booty), wondering if either of those is suitable for the secondary pump.

Takagi or Navian boiler
Taco 0015 msf3 ifc medium speed secondary loop
Gurdfos ups15-58 primary

 

[like2wheel]

275' loop x 32 btu's per ft 8800 btu's per loop
9' + 2' = 11' for head need to know how many loops for gpm and pump size
Recommend a micro bubbler for air removal. Glycol? Use only boiler / chilled water type. Minimum 30% ( for the inhibitor package) can set up for two different protection. For hard freeze or slush. Slush will not freeze hard and will not break piping. Wouldn't recommend a permanent fill line. With a permanent fill if there is a leak and it's not detected glycol gets diluted and with a power failure system freeze. A cheap drill motor pump can fill the system and add solution if needed. Low water cut off for protection.

I have a 5 gallon bucket of Cryotec 100, my boiler manual says to not go over 35%, so 30% sounds good.
My boiler manual says it has a built in pressure sensing LWCO set at 6psi.

 

[fitter30]

Haven't seen with either boiler glyco mix or low water pressure cut off.