Help with hydronic radiant heat

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Zl700

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Good pictures
The main issues are now that I've seen pictures:

1. No boiler pump, this should be primary/secondary piping
2. Mixing valve is too small (high C.V.) restricting flow (3/4 passes only about 43,000 BTU's)
3. Loops are too long
4. 1" piping to small (would be OK with 6 1/2" loops)
5. Manifolds are too small for that many loops (that looks like ones for 3/8" loops)
6. A detailed radiant design may determine that plates are needed, if plates wont do it or enough, supplemental heat may be required such as a kicspace heaters, convector, air-ocer hot water coil or baseboard, probably run on high temp zone
7. When finished there will be way to many loops on one pump and manifold, as you are feeling now already. Strong consideration should have been given to using 2 pump/manfold/mixing valve setups (up and downstairs)
8. Tubing is a bit close to joists that act as a heat sink, should be closer together for a true 8" cc.


If you followed the design, Fred needs some instruction on proper design and installation techniques. You wont even see such a farce in a boiler manufactures instructions.
 

alfpark

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Good pictures
The main issues are now that I've seen pictures:

1. No boiler pump, this should be primary/secondary piping
2. Mixing valve is too small (high C.V.) restricting flow (3/4 passes only about 43,000 BTU's)
3. Loops are too long
4. 1" piping to small (would be OK with 6 1/2" loops)
5. Manifolds are too small for that many loops (that looks like ones for 3/8" loops)
6. A detailed radiant design may determine that plates are needed, if plates wont do it or enough, supplemental heat may be required such as a kicspace heaters, convector, air-ocer hot water coil or baseboard, probably run on high temp zone
7. When finished there will be way to many loops on one pump and manifold, as you are feeling now already. Strong consideration should have been given to using 2 pump/manfold/mixing valve setups (up and downstairs)
8. Tubing is a bit close to joists that act as a heat sink, should be closer together for a true 8" cc.


If you followed the design, Fred needs some instruction on proper design and installation techniques. You wont even see such a farce in a boiler manufactures instructions.

I spoke to him today and the only issue on my pics he had was the mixer and taco does that. that mixer is a 1" it comes with those nipples.
http://www.blueridgecompany.com/image/item/320
 

Ottawa_HVAC_Guy

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The simple answer here is that you don't have enough tubing in the floor to heat the house. There may be some design issues also, like 400' loops and possibly some pipe size issues but I will bet that you just plain are not getting enough heat into the house. A couple of toe space heater or even some fin tube baseboard will fill in the difference.


Good pictures
The main issues are now that I've seen pictures:

1. No boiler pump, this should be primary/secondary piping
2. Mixing valve is too small (high C.V.) restricting flow (3/4 passes only about 43,000 BTU's)
3. Loops are too long
4. 1" piping to small (would be OK with 6 1/2" loops)
5. Manifolds are too small for that many loops (that looks like ones for 3/8" loops)
6. A detailed radiant design may determine that plates are needed, if plates wont do it or enough, supplemental heat may be required such as a kicspace heaters, convector, air-ocer hot water coil or baseboard, probably run on high temp zone
7. When finished there will be way to many loops on one pump and manifold, as you are feeling now already. Strong consideration should have been given to using 2 pump/manfold/mixing valve setups (up and downstairs)
8. Tubing is a bit close to joists that act as a heat sink, should be closer together for a true 8" cc.


If you followed the design, Fred needs some instruction on proper design and installation techniques. You wont even see such a farce in a boiler manufactures instructions.

You're missing a pump! You need 2 pumps to make this work. Your loop designer might have given you a passable design, but the heat generation (boiler, boiler piping, pump and controls) design is completely wrong. You can't possibly ensure that you have enough flow through your boiler (or infloor system) with that piping arrangement. As zl700 mentioned: you MUST have a primary-secondary pumping arrangement. Start with a proper boiler design, then see if there are any other problems. Primary-secondary pumping systems tend to have much fewer problems than simple pumping systems.
And it doesn't mater which 3-way valve you are using - you have to install 2 pumps for this to work properly. Cutting corners always ends up with problems...
 

rrekih

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I have also put in a system that is mounted under floor.
I need to do some fine tuning but all seems to be ok.
I looked at your pictures and see that you mounted the pipe away from the joists.
I mounted mine up as tight as possible to the joist.
One thing I did notice is the mounting clips seemed to be spaced far apart.
I used talons with no more then 2ft apart.
The longest run I have is around 300ft, knowing full well that I was going over the recommended max 250ft.
I am only doing approx. 1500sq. ft. and use a Grundfos 26-99 superbrute but plan to change to primary / secondary system.
With the sq. ft. you are using you should have 2 pumps.
 

Zl700

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Don't put the tubes next to the joists, the joists serve as a heat sink transfering heat off the floor you wish to heat.
 

S+W

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What ever came of this situation and design? I am looking at the same designer but for a slab situation. Not getting the warm and fuzzies here.

TIA,
S+W
 

Ballvalve

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Well, I see this is a very old resurrection. This guy just needs some HIGH HEAD pumps. I have one grunfos beast that runs 6 loops. Also when you guys do radiant on a wood floor, do it right and put sleepers ON TOP of the subfloor and invest in some cheap 4 or 5 to 1 mortar to fill it all in. THEN lay your flooring - Now you are not working upside down and your heat transfer is up 200%. And you have a virtually fireproof layer between floors. - along with some thermal mass which you have none of with that stupid upside down staple up perversion.
 

BadgerBoilerMN

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First, a proper heat load analysis performed on dedicated radiant floor heating software will tell you tube size, length, flow and average water temperature.

A proper radiant floor heat load would have told you if your plan to go "plate-less" - at any design temperature - would satisfy the load (thermostat) before you started your project. Whereas, it is true that nearly all common floor coverings are compatible with hydronic radiant floor heating, it is also true that you have to have the system designed by a professional (few online radiant floor suppliers qualify) to have reasonable expectations of success.

I have a new 3/4" solid oak over 3/4" plywood decking and am quite comfortable with design water temperature of 110°F here in Minneapolis. This means, when it is -13°F (our outdoor design temperature) the house will be 68°F. My design software dictated the use of heavy extruded aluminum plates to reach my design goals. By contrast, my first sub-floor hydronic radiant system, circa. 1991, was a straight staple-up and still operates at 180°F and required several panel radiators to supplement the low-output of this crude application. I experimented with fiberglass, foil-faced and kraft-backed. I also installed bubble-foil and compared the performance. It is now the very rare design that I will allow a bare tube staple-up or suspended tube radiant panel. In vast majority of cases, both new construction and retrofit, some type of proper efficient emission plate must be used to get reasonable, efficient or even effective heat transfer.

You could still do a heat load if you really want to know what temperature you must operate at to be comfortable or just crank it up until the house is warm.

By the way, bubble foil is a scam, professional radiant floor people can find no useful purpose for it. Those who advocate its use for radiant floor heating should not be taken seriously.

http://www.healthyheating.com/Page 55/Page_55_o6_bldg_sys.htm

Before spending money on questionable radiant floor heating practices, look for a former RPA certified designer. Certified designers were tested by an independent, third party, process.

http://www.badgerboilerservice.com/images/RPA.pdf
 
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