heat loss completed/ need feed line recomendations

mustang_gt_350

I posted another topic on head calculations and was directed to use slant fins heat loss calculator. I did so, on the computer not my cell. And here are my results.

The total is 68619 or 56381. This was done with internal temp at 72, and outside temp of -1.

The higher estimate is reflecting the sunroom being added to the living room (one big room) without any window/insulation upgrades.
The lower number shows the living room, and the sunroom as a non heated room.

I tried to lean on the less insulated options as much as i could and thought would be reasonable. How much should be added to this for a error factor?

This is a 1940's built house, that is roughly 26x26 with a basement that is around 18x26 that is not finished. I am slowly gutting and reinsulating and replacing windows as time/money allows.

I mainly posted the head loss calculation question due to a local outdoor boiler guy saying that there was no need to run anything over 1" feed lines, however that was after he said my 75k btu estimate was low and i should double that and thats about the BTU i would need for my house.

Anyway, With this known heat load. What feed line do you recommend? My round trip from the furnace location would be 160ft. I would rather spend a little more now on larger lines, than have to push it with a high power pump for the next many years.

Ironman

1'' will be sufficient to move 8 gpm @ 16.6 ft.of head. That's assuming the head loss of only the pipe and using a ups26-99 circulator. If it has to push through a heat exchanger too, then it would be prudent to go to 1 1/4" pipe. This is with a 20* delta T, which is what most radiation is sized for.

If you were only connecting a radiant floor to it which requires substantially lower water temps, then you could run a 30* delta T on the boiler side and the 1" pex would be sufficient even with a HX in the circuit.

There's no pat answer here as you're probably beginning to see that hydronics requires engineering EVERY component into the equation. It's kinda like chess: you have to think five steps ahead to know what move to make now.

We really need to know what your total plan for the heating system is. Not just your heat loss, but what type of emitters are you using besides a radiant floor? Can the floor produce enough btus to heat the house at design temp? With good quality extruded aluminum heat transfer plates, 20 btus per square foot is the best you can expect. Will you need to supplement it? If so, with what type of emitters?

mustang_gt_350

I Have looked at that pump before while browsing around the pump options. How much advantage does a multiple speed pump have over a fixed speed?

I noticed the planning of this is more in depth than i ever thought. When i first got the idea to switch to this i was thinking "its just pipes under the floor, thats a cake walk" Now after doing some reading I have noticed that there are a TON of factors, and planning that is involved in doing this. No biggie, i like learning new stuff and am very into mechanical stuff. Thats why i figured i would start out with what feeder sizes and work my way around them as i plan it out, and if something comes up later i can go back and scribble that part out and rewrite it lol.

The plan is total radiant floor heat. But from looking at the BTU requirements for each room and seeing your 20btu/sqft I don't think its possible to do that only. The only room that is able to come close to the calculated amount is the bedroom that i just redid from last winter into late spring.

Now to the supplementation. I looked around after i made my heat load post for options. I actually kinda like the idea of the kick space heaters made by beacon morris, i believe it was a k42 and they say they are made for lower water temps so it would keep my setup simple.

Now i have a question. Over the reading i have done why do some places say you are able to get 35+btu/sqft, and you say 20? Is 20 the safe number, or are they just trying to push their stuff and its unrealistic?


2nd question, more of a thought i guess. I am a little confused on the Delta T. I know thats the temp that is actually being released into the heated room. But doesn't it always change based on indoor temps? Meaning if the room is 70 and the feed water is 130 it would be different vs if the room was 50 and the water is 130? I am still trying to learn more of this, and how it is planned. Or is it designed at 20, with the understanding it fluctuate based on demand variables? If you have any links to more info on the Delta T stuff and would want to include them so i can read more on it i would be grateful.


Thanks again for you help.

Ironman

20 btus per square foot is with extruded aluminum plates attached to the bottom of a wood floor with an R value of 1.5 or less. That depends on the thickness of the wood and the R value of the floor covering. This is the most common scenario when adding radiant to existing flooring. There are other methods than can produce a higher output, but they are more complicated and much more expensive. See the attached chart:




Delta T is the temperature difference of the fluid entering and leaving a component. It's a key factor in the universal hydronics formula: BTU = (gpm x 500) x delta T. I'm using it in reference to your supply and return water temps.

mustang_gt_350

Ok i think I am understanding a little better now, and it looks like extruded plates and supplemental heat is going to be the best route.
My floors are oak 3/4" tongue and groove that are 2" wide. \

So what are everyone's opinions on the kick space heaters for the supplemental heat?

How well do the decorative wall mount radiators work?

Also, i know there is the option for radiant wall, that i actually like the idea, however it looks to be more expensive, and i don't really like the thought of a forgetful nail being ran into the wall while she hangs a picture.

KC_Jones

mustang_gt_350 said:

My floors are oak 3/4" tongue and groove that are 2" wide. \

If you are doing plates underneath of this, have you looked under the floor yet? Many times the nails to hold down that flooring protrude through the sub floor and can make the underfloor difficult.

mustang_gt_350

The small section i had to access to do some fixing from the doofus guys that cut the T&G flooring there wasn't anything sticking out. If so no big deal i can grind them down. when they redid the house to forced air they ran the ductwork inside the rooms. So they cut the flooring for the vent running parallel with the floor joists next to the wall. so needless to say it was super soft since it was being held by the nearest one that was 16" away.

The sub floor and floor are the same thing. They ran the T&G oak across the floor joists and that is the floor.

Robert O'Brien

"I mainly posted the head loss calculation question due to a local outdoor boiler guy saying that there was no need to run anything over 1" feed lines, however that was after he said my 75k btu estimate was low and i should double that and thats about the BTU i would need for my house."


Could triple it to be sure!

Ironman

mustang_gt_350 said:

Ok i think I am understanding a little better now, and it looks like extruded plates and supplemental heat is going to be the best route.
My floors are oak 3/4" tongue and groove that are 2" wide. \

So what are everyone's opinions on the kick space heaters for the supplemental heat?

How well do the decorative wall mount radiators work?

Also, i know there is the option for radiant wall, that i actually like the idea, however it looks to be more expensive, and i don't really like the thought of a forgetful nail being ran into the wall while she hangs a picture.

What about using the forced air for supplemental heating?

Toe kick heaters have their place, but that's typically in baths and kitchens. Panel rads with TRVs would normally be my first choice.

njtommy

I would just install a hot water coil in the duct work or right above your Ahu if you have AC in the house. That would be your best bet. It's also nice to have a whole house humidifier to.

Check out http://www.aquecoil.com

They have ones that are a direct fit for over top your Ahu. As long as your supply water temps match and your btus need match up it would be very easy to install.

mustang_gt_350

What about using the forced air for supplemental heating?

Toe kick heaters have their place, but that's typically in baths and kitchens. Panel rads with TRVs would normally be my first choice.



I'm really trying to get away from the forced air heat. I hate how noisy it is, and the fact that all the ductwork is able to be seen from all of the rooms where it goes up along the walls on the first floor to heat the 2nd floor. when i mean being seen, i mean they cut holes in the floor of the 1st floor, ran the rectangle duct up the side of the wall and cut a hole in the floor of the 2nd floor for the vent. I think they overshot the btu load when they installed the system as it seams after the blower does kick on after the warm up stage (lack of technical term) the burner only runs for around 2-3 minutes after and then it shuts down and then the fan later after the cool off time. When i'm saying noisy, I'm not a picky person about things, but when it turns on the TV has to be turned up, and there is a definite whistle from the intake side and a very noticeable blowing noise from the output vents. We haven't used it much in the last few years. Just enough to exercise it now and then, and very occasional use in the spring and fall. I bet it hasn't burnt more than 30 gallons in the last 5 years.


I have been heating with a hotblast 1557m With its own temporary ducts that i unhooked from the oil furnace AHU, and just feed it from the hotblast. Its far from perfect, but its cheaper than oil. The hotblast has many of its own issue's that would be a whole post in itself, but I'm not worried about it as it will be on its way out in the fairly near future hopefully.


I'm fine with panel radiators. I was just thinking the kick panel's could be hidden under the vents that are there now with the floor kits, or in the walls and wouldn't take up any room since my house isn't the largest to start with, and when the rest of it gets remodeled along the way i wouldn't most likely need them anymore anyway.

That pic is of the duct feeding the bedroom above my dining room.


'

njtommy

I can see why you don't want to use your ducting for heating.

mustang_gt_350

Yeah, now imagine that in every room of the house downstairs, and some of the rooms have more than 1 running up along the wall. Not to mention that some are round, and some are the rectangular lol.

mustang_gt_350

I know this isn't going to be an overnight change. I'm just trying to plan it out so i don't rush it and think later well i should have done it this way... I know there is always afterthought, i'm just trying to keep it to basic things that i can live with.

keyote

I used the free 30 day loop cad program its a pretty easy cad program that allows you to draw your entire house and specify custom or use templates for wall floor window etc r ratings and to draw your loops it will give you all sorts of calcualtion automatically as you change the design like flow head delta t water temp and every thing else.and of course a very accurate heat loss and cooling calculation by room and floor and loop and manifold and project. now after 30 days you can no longer export or make copies or make permanent changes, but you can still make changes while the program is open once closed it reverts to the design as it was on day 30. it doesnt do near boiler piping like siggys program which can do loop design in a less glamorous way. I would have as much reading done ]idronics free to read online] before i started my loopcad design i would also have very exact paper version of house so as to quickly transfer it to loopcad and have as many days up and playing around as possible. it has built in video and text tutorials relly easy to draw with mcucj simpler to autcad but i would get familiar with the videos before i began my download you will still refer back but youll be fairly familiar.

mustang_gt_350

I actually downloaded it a few days ago, but haven't installed it as i was waiting to get as much info/data as possible before i started my trail. For once i am one step ahead of you guys