I have homeowner/DIY designed a radiant heat install for my home. I utilized LoopCAD for the design and heat loss calculations. My plan is to convert from baseboards & oil heat to gas heat and constant circulation radiant with outdoor reset to control inside temperature.
My LoopCAD drawing claims a required heat output of 31 k btu. I have an ~1,800 sq/ft ranch- above ground floor is 1k sq/ft and partial below ground (walkout) is 850 + garage. I am in the process of renovating 75% of the home so I am trying to air seal it (closed cell spray foam) and provide proper insulation to make this the most efficient install as I can get it to be.
Currently I have Uponor 1/2" HE-PEX installed with a suspended pipe design using clips (more below).
Products I have purchased:
-Tekmar 360 Control with outdoor & indoor sensors
-Uponor EP manifold- 10 ports total
-Thin metal 4 ft. eBay heat spreader plates (4" wide), about 400 of them
-Grundfos 15-55F pump
Pictures of my piping design & control strategy are below.
I have a few questions:
1. I was told that doing the thin heat plates would be superior to a suspended tube design. Is this correct?
2. LoopCAD tells me that I should use 3/4" pipe to supply the manifolds due to an estimated flow of 3 GPM. If I make the radiant heat system the primary boiler loop is restriction of flow bad for the boiler? If I change to 1" or 1.25" primary piping is the lack of pressure bad for the manifolds? Maybe the solution is to make a 3/4" bypass with ball valve?
3. My control concept is to have the Boiler ODR determine the temperature of water to produce and the Tekmar to determine the calls for heat and fire the boiler based off feedback from the indoor sensors. Also this will prevent the boiler from short cycling (I believe?). Can I just jump the thermostat terminals on the Tekmar or should I connect them to my Nest Thermostat and use it as a high heat cutoff by setting it to say 75 when my Tekmar indoor desired temp is 70?
4. Recommendations on boilers? My plumber had me leaning towards a Navien unit and I would do a separate wall mounted on-demand water heater too. I've also looked into Bosch gas burners recently too.
5. Is a fully modulating boiler built to run 24/7 without input from my Tekmar or a thermostat but just operating off of an ODR control? I feel like this would be the simplest setup?
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My LoopCAD drawing claims a required heat output of 31 k btu. I have an ~1,800 sq/ft ranch- above ground floor is 1k sq/ft and partial below ground (walkout) is 850 + garage. I am in the process of renovating 75% of the home so I am trying to air seal it (closed cell spray foam) and provide proper insulation to make this the most efficient install as I can get it to be.
Currently I have Uponor 1/2" HE-PEX installed with a suspended pipe design using clips (more below).
Products I have purchased:
-Tekmar 360 Control with outdoor & indoor sensors
-Uponor EP manifold- 10 ports total
-Thin metal 4 ft. eBay heat spreader plates (4" wide), about 400 of them
-Grundfos 15-55F pump
Pictures of my piping design & control strategy are below.
I have a few questions:
1. I was told that doing the thin heat plates would be superior to a suspended tube design. Is this correct?
2. LoopCAD tells me that I should use 3/4" pipe to supply the manifolds due to an estimated flow of 3 GPM. If I make the radiant heat system the primary boiler loop is restriction of flow bad for the boiler? If I change to 1" or 1.25" primary piping is the lack of pressure bad for the manifolds? Maybe the solution is to make a 3/4" bypass with ball valve?
3. My control concept is to have the Boiler ODR determine the temperature of water to produce and the Tekmar to determine the calls for heat and fire the boiler based off feedback from the indoor sensors. Also this will prevent the boiler from short cycling (I believe?). Can I just jump the thermostat terminals on the Tekmar or should I connect them to my Nest Thermostat and use it as a high heat cutoff by setting it to say 75 when my Tekmar indoor desired temp is 70?
4. Recommendations on boilers? My plumber had me leaning towards a Navien unit and I would do a separate wall mounted on-demand water heater too. I've also looked into Bosch gas burners recently too.
5. Is a fully modulating boiler built to run 24/7 without input from my Tekmar or a thermostat but just operating off of an ODR control? I feel like this would be the simplest setup?
