where the hell are my BTUs

keyote

I cant seem to raise the temperature of the rooms. At first i thought I was wrong that i could get away without insulation underneath the floor for a bit, but even at design temp[127] on a 65 degree day it wouldn't budge.
So i stuffed R30 fibreglass between the joists against the underside of the floor from below, which is exposed in prep for that floors renovation. The risers not insulated yet so although I can feel theyre hot and definitely hotter on supply than return I confirmed with the manifold thermometers just below the floor. Im running at delta 10 which is what loopcad was designed around so this is first test since insulation almost an hour no temp rise.Now I know some were a bit sceptical of my method and I wouldnt repeat it but the fact remains i once did a underfloor from above it was insulated but had no plates and was only held in position with brackets this was the 'design' given to me at the time by the internet supplier. LOL live and learn thing is though it worked great it came up to noticeable heat in 15 minutes.
For those not familiar with my sad story Im 1/2" reifing 02 pex usually 12 OC though i have the perimeters tighter the floors are 85%; tubes between 3/4 ply sleepers on top of aluminum flashing on subfloor with 3/4" hardwood above poor mans warmboard i thought.the other floors are similar except on top is 1/2''cement board and 1/4'' tile. Ok maybe not near as good as warmboard or real plates, but the heats goyt to be going somewhere doesnt it, how can this be worse than staple up or that job i once did? and loopcad was programmed with that set up and claimed i was going to be over heated, and wirsbo say 8-12" is standard spacing. This is going to be a nightmare tenants with no heat and all this work.

kcopp

How much contact does the tubing have w/ the floor? tubing is 5/8" w/ 3/4" sleepers.... you could have few parts of the tubing actually touching.... What temp are you running?

Gordy

Buy an IR thermometer. It's a handy tool.

keyote

Kcopp that was gordys objection when he first hear what i did,as he pointed out only the top of the tube is in contact with the flooring above, it was too late when he convinced me it was not anything like warmboard, I had hoped it would not be so dire since as i said it had worked so well once under even worse conditions and my original 'designer' had not tried to dissuade me. I mean were therre always plates? i could see lower performance i cant beleive im getting zero wheres the DT 10 going? the water is going in manifold at 120 coming out 110 the loops are about 200' the pumps an speed two now

kcopp

Bump up your temp. Try 130F

keyote

Hat thats exactly what I was hoping praying someone would say except is there really much mass with all wood not concrete?

Kcoop I will try a bit higher its actually 127 at the boiler which is supposed to be design and as high as i can go without exceeding 84 degree surface on floors but riser not insulated so Im losing on way up to manifolds.

so if it takes so long [i hope] to get up to temp sounds like Im not going to be waiting for heat calls but somehow running it constantly?

Gordy

Mass can be anything...well with mass. Even insulation. There is a step progression. Water heats tube, tube heats plate, plate heats wood, wood heats objects. Any break in conduction in that loop hinders performance. The temps you are using in the reset curve are for a system that is maintaining its setpoint. Throw a setback at it, or start off below setpoint when turning the system in initially it takes a fair amount of time to catch up.

This is why setbacks in a radiant system that is tuned to ODR is not recommended.

keyote

yes Gordy i took the setbacks out of the tstat and programmed radiant type heat not sure what that does but i also started with 1-2 calls per hour max

Gordy

Patience. It's 65 degrees outside. What are you trying to achieve for a setpoint??

Remember the greater the difference in a delta The faster the btus are transferred.

I'm referring to the floor panel, and the rooms temp. Just because you are using 115 degree supply temp does not mean that is the floor panel temp.

Buy the IR thermometer. It will tell you, and help you understand many things. I have a feeling you will be using it a lot.

keyote

I ordered the IR and a new multimeter no wonder the chinese added 3.4 trillion in debt lat year they give this stuff away on amazon.Didnt realize how cheap they were now. yes stripping i expected without plates.
Is there any truth to this radiation goes through everything like neutrinos and i must have reflective mylar bubble wrap and keep it clean i used unfaced batts and i figured if true the flashing is reflecting
I put the set point at 74 on the cooler apt to give it some room, the apts were 75 and 70 and its 59 outside the cooler apt is now 71 the other still 75 its been two hours.Im going to keep calm and go to bed keep the faith. I was trying to acheive confirmation that last weeks fail was only because insulation was not in.

keyote

it ran all night [is that going to wear out zone valves?] and the rear cooler apt gained another degree by 730am but the other apt was still 75, however outside temp had dropped 11 degrees its now 48. the brick foam and triple panes tend to make for slow swings though.
Its 9am now and front apt is up a degree to 76 [he still has his ac units in windows] it seems like its going to be inadequate come winter, now the mass is loaded i guess the theory is it can start show its stuff? I hope so.
The sort of good news is the dhw called during the night and the heat came on afterwards which was a surprise because previously it would display 'setpoint met' after a dhw call. My theory was the water in the pipes was hotter than the heating parameters, i still think thats likely but after my shower this morning which triggered a dhw call interruption i left the boiler alone to see if it would come out of that 'setpoint met' on its own which it does but it waits till pipes are cooled significantly beloww heating parameters, which is why i thought it was some kind of a lockout setting despite its name.I suppose in a way its a good setup if youre worried about loop temps and floors, but it takes a while to cool i had already thought i might extend the dhw post purge, noticing the system was still quite a bit hotter than tank after call.

Gordy

Are you trying for sauna temps? What was the design set point when you designed the system?

keyote

I was only trying to make sure the system could raise the temp or not before blowing brains out. Because the insulation and windows work so well, even the cooler apt has not yet gotten below 67 degrees and the heats only run a couple of hour long attempts until last night. So to trigger the system I had to set it fairly high as luck would have it we just had a 74 degree day when the underfloor insulation got finished so started at 75 and 70 [one apt is almost always at least 2 degrees cooler].
I dont want to find out in the dead of winter when the grounds too frozen to bury me that the system doesnt work and my tenants are suing me.
News of my demise may be premature though, the cool apt hit 74 so i turned setpoint down to 70? -and room dropped to 73 a minute later odd. We have a couple cool days coming we will see if it can maintain now its warmed up.
Ill have to check I think 70 or 72 was the default design and I left it.

keyote

My next problem assuming this one is solved is balancing. i have all the loops wide open and they seem fairly evenly balanced its up between joists so hard to tell exactly.I suppose Ill need to play with the Delta t pump setting some more to give it a fair try but while it didnt seem like it would high limit it also didnt seem like it would stop swaying on the first trial. Maybe pump has to be considered first but do i need to do anything to the flow meters on manifold besides if they are off a bit crank down the highest a bit till even? or am I to attempts to balance them to the loop cad design day flows?
Also if one apt is a bit warmer can i balance that out with the meters on those loops?

Tinman

Aluminum flashing on top of subfloor with 1/2" tubing, 12" OC, between 3/4" sleepers with hardwood nailed to the sleepers? Do I understand that correctly?

Tinman

That's not a poor man's Warmboard. That's upside down bad design Warmboard without the tube to metal contact that Warmboard offers. Geez. If the design can't be minimally verified with math, it shouldn't be attempted. No? What am I missing here?

Gordy

I brought that up eons ago. that is like plugging in three extension cords with one having the neutral prong broke off.

Or hooking up three garden hoses, and forgetting to screw one together.

Or having a cooler full of ice cold beer, and forgetting the ice........


Or.......shall i go on?

The conduction chain is shoody. The only recourse is turn up the SWT. This will rear its ugly head at design temps, and below. Grab the sweater.

Harvey Ramer

Water design temp should only be slightly lower than a staple up job. It would actually work better if the air space was 2" with the tube suspended in the middle. That would allow convection to occur. Right now the air gap is acting as an insulator.

Gordy

He's got hardwood flooring. Could be an issue. Maybe not.

Harvey Ramer

It shouldn't be an issue if he put a humidifier in the room and kept it around 50%. Heat alone doesn't damage the wood. Uneven drying does. How hot does the surface of a floor get when the sun lays in through the window?

keyote

I made a stamp at first with some steel rod welded to angle it was a lot of trouble and not great effect so i stopped bothering.

anyway my combustion readings were 08.5 and 016, withing parameters but low end Ive heard guys are prefering 9.2-9.5 higher end boons having trouble at my same reading, im not i dont think but limited use so far. he has a 40' flue i have a 4' both at sea level he might have static pressure im thinking messing with the fan rpm interpretation? any thoughts about these higher numbers being ideal

Tinman

Harvey - I don't disagree with that but why would anyone do either of those 2 designs. Staple up or suspended? Underperformance, inefficiency, waste of time, waste of money.

Tinman

I have seen so many of those systems that don't work and some that will never work.

Gordy

Harvey Ramer said:

It shouldn't be an issue if he put a humidifier in the room and kept it around 50%. Heat alone doesn't damage the wood. Uneven drying does. How hot does the surface of a floor get when the sun lays in through the window?

The sun usually warms an area of the floor evenly. Although not usually the whole floor.

Depends also on how much SWT is needed.

Stripping at 1' centers different scenerio. In my mind. Depends on the width of flooring, and how it is sawn. The narrower the better, and quarter sawn is best.

Harvey Ramer

@Gordy I certainly don't disagree. Both of those types of tube applications suck in performance.

If it doesn't perform he may have to switch to floor warming with supplemental radiation for the room.

keyote

i do have spray foam, insulation triple pane windows, the load was about 16 kbtu for 1100 sf and theres two kitchen laundrys and bathrooms up there

keyote

it needs 16k on design day theres nothing else, so i did the loss in loop cad and on that floor i drew the loops as already installed it asked the assembly and i checked for one similar to what i did it gave me a water temp and flow for design day and the surface temps were at or below 84 which was another parameter i plugged in. so according to loop cad its supposed to work with design day water at 127 and a surface temp 84 or below. I was relieved at that confirmation now Im worried again, i do worry a lot which is the frustrating part i always over think and research and somehow may have gotten it fatally wrong. Feel like i looked all day for my keys and they were on the counter all the time.I decided a couple months back to do the rest of the house as radiant ceilings with these foam boards with laminated plates embedded if i have to i can redo the ceilings up there Ill lose tenants and rent Ill live.
Did you see where in my first run the delta t pump kind of seesaws with the boiler they take turns running up and then back down to 15% no lock out but its wasteful. if the pump could be adjusted to not overshoot i think it could be tuned out, its manual even says it will run all the way up when it detect a if you could dial down how far it was allowed to speed up or better how fast, a ramp delay but it wouldnt need to be fancy stepped just a simple dial

keyote

See if I can remember, after the roller coaster,I switched the pump to fixed speed one, and it worked i believe at 10% mod, temps were 102/92. I know on speed two it ran that floor and the cellar finn tube loop at 35%. modulation, that was at 127 swt. I havnt balanced so its wide open, but i can change the modulation by changing the SWT.
youre saying multiply the the known btus using the mod rate less the DT by the flow ?
Now the floors warm and its 70 degrees outside i doubt i can unload many btus.

Boon

I have a couple spare runtal units if you need 'em.

>>> boons having trouble at my same reading

I WAS having ignition trouble at 8.5. My reading is 9.0 now. Mostly good working order now.

Gordy

Delta t is what facilitates btu transfer. If your room is 73' and the floor is 80? (Get the IR thermometer yet)?

keyote

the IR did come but it hasnt been cold enough to call for heat.maybe next few days will need a tepid pre heat a good chance to see how well it can deliver very low temps been so busy with moving out of last room i need to demo for under slab insulation that i havnt really played with it on the heat side.

what stopped me the last time waas not really being clear on how to incorporate the outdoor and the water temps.