Joined on May 31, 2005
Last Post on April 7, 2011
@ April 7, 2011 11:41 PM in Getting the wild ones this yearAnd where else do you go but to "The Wall"
My last post was inquiring about tubing the grade below a freezer. Now I have a customer who has a 32x 60 greenhouse under construction and wants to do root zone heating. Anyone ever done that?
My questions are:
Do you insulate the sub strata, like down about 2-3 feet? He wants to grow tropical fruit like bananas and citrus and hopes to keep the trees in pots to move outside in the summer. (These will be very large pots, i.e. fork lift movable)
I know the edge insulation would be critical as usual, but then, if you insulate the "floor" at a depth of 2-3 feet you are basically creating a "tub" which I would assume could create saturation problems. Should provision be made for drainage?
The heat loss calc for the building itself is no problem but I'm struggling with how to account for heating up 40-50 tons of dirt to 55* Talk about flywheel effect.........
Any input from the resident guru's?
@ March 31, 2011 7:14 AM in Heating the ground under a commercial freezer......I would have to agree on the weight. In this particular job, which is small in comparison to many commercial freezers, the calculated load for each section of pallet rack is near 40,000#. That's each section 42" x 120". The racks are going to be 24' tall with a ceiling height of 30'. Pretty hard to suspend that much weight without some serious support underneath........like mother earth herself.
Hat tip to Paul for some excellent documentation and pictures sent my way. Thanks bro.
@ March 29, 2011 10:48 PM in Heating the ground under a commercial freezer......If you would be so kind, please send me the pictures you referred to along with any other info or notes about that project.
Thanks in advance!!
@ March 18, 2011 10:14 PM in Heating the ground under a commercial freezer......Talking with the architect, his concern was that eventually, no matter how much insulation you put on the ground under the freezer, it will freeze up and possibly cause the floor to heave, buckle or crack.
@ March 18, 2011 10:02 PM in Japan Nuke plants"Things are getting worse - and at least 3 of the
reactors are done for life - and have partial meltdowns; but,
containment is holding (as of last reports) so there will not be
anything approaching Chernobyl. The question is can they save the
other 4 (and those have not yet hit the news).
key item is that the plants were designed for either 7.9 or 8.2
earthquake and they got hit with a 8.9 The difference between 7.9 and
8.9 is a factor of 10 (its a logarithmic scale).
Overall I'd say the plants have stood up well given what they were hit with.
far as the US reactors. We have about 30 similar reactors here (GE
Boiling Water Reactors - BWR) - and many with the same vintage
containment. Key is that very few of these are on an ocean where
they could be hit with a tsunami an hour after the earthquake (and it
was the tsunami that took out the diesel generators).
other 70+ reactors are Pressurized Water Reactors - and I believe that
design is inherently more capable of dealing with a total loss of power
than a BWR.
The new Generation III reactors
(for example the AP-1000 which will start construction later this year
in the US) are designed to handle a total loss of power - and have
enough passive cooling to prevent a meltdown."
I haven't heard anything in the last couple days because they are in the middle of refueling the plant he works in. ...makes him a wee bit busy.
@ March 18, 2011 9:51 PM in Heating the ground under a commercial freezer......There's a chance I might get involved (sucked into) a commercial project this summer that has 28x36 freezer area which will be maintained at -20*. The architect suggested to the builder that he get in touch with someone who can give both of them some guidance. So guess who got the phone call......
I've done enough reading on the subject to be dangerous but I really feel like the one eyed man in the land of the blind. Not enough knowledge about it to be confident in what I recommend.
So I'm wondering if any of you guys have done sub-grade heating under a commercial freezer. What did you use for control? What type of substrate did you place the tubing in? etc etc.
@ December 17, 2010 10:35 AM in How's your weather?Left Wednesday afternoon about 4:30 and made it to Wausau Wis by about 3:00AM. Crashed in the back seat of the truck. (Left the truck running because it was -13* outside). Hit the road at 8AM and drove in to the twin Cities picked up the 2 wood boilers I was after and had lunch with Martin Lunde and Jim Saufferer at Broadway pizza just west of the dome....or what's left of it. There is a LOT of snow in Minneapolis that's for sure. Had dry roads across the UP of Mich and through Wisconsin out and back but Martin had called me and advised not to go around through Chicago. Glad I didn't as I would have been pulling 5 tons of weight through slop all the way back.
Last weekends big blow left us with about a foot of white stuff. One of my guys was snowed in so bad he didn't make it to work until the county came and scooped out his road with a payloader. The plows got stuck in it.
@ December 15, 2010 11:56 AM in Buderus G124x leakingDrew just called from a customers house and relayed that the return elbow on the bottom left of the block is perforated/rusted through. On the parts diagram (p/n 05407352) it appears that the elbow is secured to the block with a jam nut and gasket behind it. On the boiler in the home, it looks like it's a bushing. Things are so corroded it's hard to tell what we are looking at.
If anyone here has had one of these apart and could tell us what the configuration actually is please call Drew at 231-920-7471 . Tech service call center @ Buderus was no help in determining how this piece is actually put together. We don't want to try and take that bushing/jam nut out unless we have to. Going to try and clean up the threads and seal up with some thread cord.
@ October 13, 2010 5:03 PM in Calculating heating costs/math problemI'm asking these questions mainly for my own information/education as I don't get a chance very often to really look hard at these ICF buildings. As is the case on this job, and most in the economic armpit of the USA, commonly called Michigan, the first cost is the only thing that is considered.
Cd factors that reduce heating equipment input will be scarce for this building because of its largely uninhabited nature, so the only tangible difference would be the building mass. Other than that, the difference in R-value and AC/H are the only things that would really influence the building performance. Correct?
I looked up some records of propane prices locally since 2000 and found that they have increased an average of a little over 7-1/2% per year. I don't know if that rate will continue or what difference it would make in your model but I think that it's safe to say no fuel costs are going to go down. I listened to a webinar featuring an oil industry CEO a couple weeks ago and his position was that it is very likely we will see prices back at 2007 levels by the end of next year. Scary thought.
Thanks again my good man.
@ October 13, 2010 3:06 PM in Calculating heating costs/math problemYou wouldn't assume any difference in Cd factor for the high mass/low mass buildings?
@ October 13, 2010 8:48 AM in Calculating heating costs/math problemDesign delta T is 76* for our area. Those are the numbers from HVAC-CALC.
I used an efficiency of 95% for the Vitodens that will be running the system. I'm curious as to what factors would reduce that? My experience with those boilers applied to a low temp system shows that if parasitic losses are minimized it will easily hit that.
Of course dear sir, I will yield to your expertise in this area. I'm just a humble pipe fitter.........:)
@ October 13, 2010 8:35 AM in Calculating heating costs/math problemLocal cost of propane is running about $1.70/gl on a prebuy program. Our heating degree days are listed as 7800. I used a Cd factor of .85 for the steel building and .70 for the ICF.
Does your program factor in annual increases in fuel costs? 10 years ago propane was selling for $.59 here.
@ October 13, 2010 8:15 AM in Calculating heating costs/math problemI don't want to spout knowledge I know nothing about.......know what I mean?
I'll be out and about but we'll see if the Blackberry works in the basement of the day.
@ October 13, 2010 6:32 AM in Calculating heating costs/math problemThat would be sweet. The cost difference between the two buildings is near $110,000. Not all of which is simply attributable to the ICF part of the building.
The main source of the difference in the heat loss is the air infiltration factor between the two and then the R-value of the walls and ceiling.
The ICF proposal has a higher value in the walls of course and the ceiling will be under a ventilated attic at R-44 rather than R-19.
Heat loss came to 233K for the steel and 162K for the ICF construction.
Fuel source will be propane.
@ October 12, 2010 10:58 PM in Calculating heating costs/math problemI ran the numbers for the two building types and they are eye opening to say the least. Using the numbers I described above there's about 40% difference in heating costs alone.
@ October 6, 2010 6:19 PM in Calculating heating costs/math problemA person has to consider three primary things when developing a :theory" on how much heat is necessary to maintain a given building.
I assign more bias to the air infiltration than the R-value. A person can have great insulation in the walls and fight to heat a building with drafts around every window and door. I would also rather see a "dense" type of construction rather than nothing but siding, 2x4's, fiberglass and drywall.
Give me a choice between a tight building with R-5 insulation on the outside of a block wall and a drafty one with R-19 wood construction and I'll live happily ever after in the cement house.
@ October 6, 2010 2:46 PM in best way to find GPM of existing systemCouldn't a person measure the temp of the pipe at the beginning and end of the system and use avg output of the baseboard........say 500/ft....... and determine at least a rough flow rate from that.
Thinking out loud here.......... 10' of BB should be transferring 5000 btu total if a person uses that average output . So........where am I going with this...........??? Assuming the 5,000 is correct, reverse the usual btu formula and arrive at gpm?
5000btu / 10* / 8.33lb / 60 minutes = approx 1gpm
Oooooorr. just say ta heck with it, install a stratos and dial in whatever you need. :)
@ October 6, 2010 2:00 PM in best way to find GPM of existing systemBupkes meters are sold in the Amish store in Wapakeneta Ohio. ........;)
@ October 6, 2010 1:34 PM in Calculating heating costs/math problemI was looking at in this way.......
Given that heat goes to cold, or in other words the building is what is actually transferring the heat........ wouldn't a higher mass structure be able to use its "flywheel" to coast through an overnight dip in temperatures more easily than a low mass building? The rationale being that the high mass structure has more btu's available to give up than an equivalent low mass building.
In a low mass building the heat storing ability of 6" of fiberglass is next to nothing
compared with 4-6" of concrete.
I don't know what the correct engineering terminology is for this but I assume it exists. (Cd factor perhaps).... And I also don't know how one would quantify it but I have seen this phenomena take place in structures where the mass is on the heated side of the wall. Example being tightly sealed, large diameter log homes and ICF buildings.
@ October 6, 2010 1:05 PM in Calculating heating costs/math problemAs a point of general discussion, how far would you go with this assumption/statement.
In comparison to building with a low mass, a high mass building will have the effect of knocking the highs and lows off the outdoor temperature.
@ October 3, 2010 9:47 PM in Luxpro thermostatDo yourself a favor and return it for something different. If the seller will not exchange it ask for a refund. Failing that, just pitch it and get something else. They are junk.
Que the old HeeHaw song...........
"If it weren't for bad Lux, I'd have no Lux at all......."
:) Sorry.....I couldn't resist...........