Comments on my radiant design

[rotaxman]

Good day everyone,

After much reading and quite a few attempts at designs, this is what I have come up with. The main concern is that fluid will not flow through the mixing valves if I use only one circulator. THe reason for two mixing valves is that I have 3 types of radiant floor, concrete, pine on subfloor and tile on 1/2" concrete board on subfloor and I felt that I may want to vary the temp for each zone. THe OWB will not be in operation until next year, so that will be up for discussion in a few months but I will have the electric boiler in operation soon.....I hope, it's getting chilly in Quebec.
My first thought was to put variable speed circulators for each zone and not use the zone valves (which I may do regardless) but I don't know if that changes anything.
I calculated all the pipe sizes and flow is not a probem with 1" main header to 3/4" manifold to 1/2" pex @ 250' per loop and using a 15-58 circulator.

TIA for comments

 

[Gooserider]

Good day everyone,

After much reading and quite a few attempts at designs, this is what I have come up with. The main concern is that fluid will not flow through the mixing valves if I use only one circulator. THe reason for two mixing valves is that I have 3 types of radiant floor, concrete, pine on subfloor and tile on 1/2" concrete board on subfloor and I felt that I may want to vary the temp for each zone. THe OWB will not be in operation until next year, so that will be up for discussion in a few months but I will have the electric boiler in operation soon.....I hope, it's getting chilly in Quebec.
My first thought was to put variable speed circulators for each zone and not use the zone valves (which I may do regardless) but I don't know if that changes anything.
I calculated all the pipe sizes and flow is not a probem with 1" main header to 3/4" manifold to 1/2" pex @ 250' per loop and using a 15-58 circulator.

TIA for comments

Looks like this one sort of fell through the cracks w/o comment, so let me drag it back up - I don't see anything wrong with it assuming you have flowchecks on the C1 and C2 circs so that you don't have flow through the non-active heat maker... I think the mix valves will work alright as you have them drawn, but I could be wrong.

I would also suggest that you look at putting in buried lines that are on the big side - gives you some margin and it is better to be on the large side in terms of lower pump energy requirements... OTOH, we see lots of users that put in lines that were to small and are now having problems w/ either having to upgrade the lines or way oversizing their pumps in an effort to get more flow volume than the line should be able to do...

I also hope that you will take a good look at a gasifier as opposed to a traditional OWB, but as you say, that is something we can debate later...

Gooserider

 

[rotaxman]

Good day everyone,

After much reading and quite a few attempts at designs, this is what I have come up with. The main concern is that fluid will not flow through the mixing valves if I use only one circulator. THe reason for two mixing valves is that I have 3 types of radiant floor, concrete, pine on subfloor and tile on 1/2" concrete board on subfloor and I felt that I may want to vary the temp for each zone. THe OWB will not be in operation until next year, so that will be up for discussion in a few months but I will have the electric boiler in operation soon.....I hope, it's getting chilly in Quebec.
My first thought was to put variable speed circulators for each zone and not use the zone valves (which I may do regardless) but I don't know if that changes anything.
I calculated all the pipe sizes and flow is not a probem with 1" main header to 3/4" manifold to 1/2" pex @ 250' per loop and using a 15-58 circulator.

TIA for comments

Looks like this one sort of fell through the cracks w/o comment, so let me drag it back up - I don't see anything wrong with it assuming you have flowchecks on the C1 and C2 circs so that you don't have flow through the non-active heat maker... I think the mix valves will work alright as you have them drawn, but I could be wrong.

I would also suggest that you look at putting in buried lines that are on the big side - gives you some margin and it is better to be on the large side in terms of lower pump energy requirements... OTOH, we see lots of users that put in lines that were to small and are now having problems w/ either having to upgrade the lines or way oversizing their pumps in an effort to get more flow volume than the line should be able to do...

I also hope that you will take a good look at a gasifier as opposed to a traditional OWB, but as you say, that is something we can debate later...

Gooserider

Thanks for the comment Goose, I was starting to feel like the kid in the corner of the class that no one talks to..........lol

If the mixers work like that then they'll definately work with a circ on each zone, which I've decided would be the most effecient, using NFCS system, w/variable speed.
Circs have check valves.


I planned on 1.25" burried lines, this should allow for considerable expansion but I will go over it again before I buy them and dig. Yes, I have read too many posts from people having to dig up their lines

I started reading more about gassifier's after we started building the OWB. The OWB project has been paused until spring but it's not too late to change the design. I'm going to give it serious thought over the winter. There's an old gassifier type wood stove that was in the cottage that I can use for idea's. I think it's one of the first one's available for retail, called a Vermont Downdrafter, bought approximately early 70's, designed at a university. It burned so hot that it melted and warped the inside so bad that we had to take it out

 

[Gooserider]

I would say that if I was doing a home-build, I'd probably try for some sort of Garn variant. It also looks like one of the significant takeaway lessons from your stove experience, plus the issues that folks have had with the metal reactor boxes on the CB gassers is that if looking at gasification, the combustion chambers need to be made from ceramics or other similar material that will keep the steel protected from direct flame exposure.

Another issue to keep in mind is the need to make sure that the design provides adequate protection against condensation in the firebox - whether it be an external return water protection system, or an HX design that doesn't allow the condensation to happen, like the Garn...

Gooserider

 

[rotaxman]

good points, didn't think of ceramics

well....... with your reassurance and no other comments, I'm going to start soldering.

very anxious to feel the heat under my feet.