TimeNMoney
Member
- Joined
- Jan 10, 2022
- Messages
- 7
I just finished the plumbing of my radiant heat system. I’m running the numbers AGAIN (before startup) and looking for some opinions on what to expect when my primary loop has a lower gpm than my secondary. I expect the secondary to pull from its return to make up the gpm it needs from the boiler through the common pipe.
Scenario: primary runs at 4gpm, tankless set to 120. At a 20* delta from the secondary, that requires 6gpm to the zone loops- If I crunch the numbers I should expect a zone supply temp of 113 right?
Considering that the delta T is gonna be super wide upon startup and tighten as the slab stabilizes, I should expect my zone supply temp to start out low and and slowly increase to the boiler set point right? (Chances of shocking a cold slab seem pretty thin)
So, as it stabilizes and the delta T narrows to around 10* the tankless is going to open up the flow/lower the firing rate because it doesnt have to increase the temp of the return so much...I think. Is there a way to use this behavior to increase the delta T in order to force the heat source to condensate? Is it worth tuning it that way? Thanks in advance
Scenario: primary runs at 4gpm, tankless set to 120. At a 20* delta from the secondary, that requires 6gpm to the zone loops- If I crunch the numbers I should expect a zone supply temp of 113 right?
Considering that the delta T is gonna be super wide upon startup and tighten as the slab stabilizes, I should expect my zone supply temp to start out low and and slowly increase to the boiler set point right? (Chances of shocking a cold slab seem pretty thin)
So, as it stabilizes and the delta T narrows to around 10* the tankless is going to open up the flow/lower the firing rate because it doesnt have to increase the temp of the return so much...I think. Is there a way to use this behavior to increase the delta T in order to force the heat source to condensate? Is it worth tuning it that way? Thanks in advance