quantifying $$$ savings...

jpf321

zamzar worked

thanks arches .. i tested the conversion at zamzar and it worked without error .. thanks for that .. sometimes i use little idiosyncratic excel functions that don't convert .. but this was fine. 

DavidK_2

Interesting

the way I read this when you put the vents back on your furnace ran longer - using more fuel!  But I assume your house was a more uniform temperature (since steam got to that top radiator faster)

jpf321

now we're getting interesting ...

(OH SHOOT...I MEANT THIS TO BE IN THE $$ THREAD)







Now that's interesting ... the cycle right after my pressure cycle ..

my rad got hot in 1/2 the normal time .. then I guess the vent closed

and started to cool .. then the vent must have opened again an heated

again .. see the cycle labeled 10:22 at top...and the cycle after that

the rad almost didn't even heat all across.



another intersting

thing is that my rad max temp was only 158dF .. which could be a

function of the way I mounted the TC to this rad as opposed to the

other rad..but any temp over 100 is really valid for determining steam

presence.



without my pressure cycle (which was caused by a

jump in t-stat +3dF) .. all other cycles were about averaged 0:35m ..

with the pressure cycle, the avg was 0:43m



my avg time to rad

was 0:25min where before it had been 0:22min on the far-rad .. but

again, it may be due to the way the TC is mounted and perhaps the rad

has to get a little hotter to register on the TC.



and lastly, my flue temp dropped a few dFahr

jpf321

to enclosure or not?

after a very spirited discussion abour radiation vs convection over here yesterday .. i decided that a test regarding rad enclosures would be interesting ..



you should know that for the last 9wks, i have been running without the tops on my rad enclosures .. they still have sides and a grilled face ... so last night .. i put the tops all back on .. at least on the 1st floor where the stat would be effected ..



it seems that it caused for only slightly longer runs .. like an extra 3mins per cycle .. where I had not cycled on pressure in several days (during normal runs), when i put the rad tops back on on I cycled 1 blip on 3 of the 4 following cycles .. in addition, the first cycle following the top installs, my rads had to heat up a fair amount more (20dFahr) before satisfying the stat .. but once that first cycle had passed, the rads heated only back to "normal" levels .. in general, adding the covers added about 2mins to each cycle.. or an extra $5 of fuel every 3days. (about 9cycles a day at 1.9GPH @ $2.50).. or $200 for 120day heating season.

David Nadle

You have to control for degree days

Outside temperature could easily be the cause of different run times. I would add up a weeks worth of run time and divide by that week's heating degree days.

jpf321

thanks for pointing that out....

thanks for pointing that out .. it was actually about 7dF(windchill) WARMER during the longer run times WITH the enclosures. but you're right, my sample size very small, i should run for a week with and week without...but don't forget that HDD is simply a daily average under 65dF.



windchill WITHOUT enclosures:

23:00 - 25d

00:00 - 25d cycle 0:41 -- added water, shut off for 2mins while adding (actual burn 0:39)

01:00 - 24d

02:00 - 24d cycle 0:35

03:00 - 23d

04:00 - 22d cycle 0:34

05:00 - 22d

06:00 - 21d cycle 0:36

07:00 - 21d



windchill WITH enclosures

23:00 - 32d cycle 0:40 (+1min) (+7dF)



00:00 - 30d (+5df)



01:00 - 30d cycle 0:40 (+5min) (+6dF)



02:00 - 30d (+6dF)



03:00 - 30d cycle 0:39 (+5min) (+7dF)



04:00 - 29d (+7dF)



05:00 - 29d cycle 0:37 (+1min) (+7dF)



06:00 - 28d (+7dF)



07:00 - 28d (+7dF)

David Nadle

HDD

I don't understand why wind chill would be an appropriate temperature for comparison. Your house doesn't feel wind chill. Yes, on windy days there will be greater convective heat loss, but the the outside of your house can't get any colder than the actual temperature.

jpf321

windchill

well as you said, and has been said on the wall before, wind has alot to do with heatloss and so I am using a standard of windchill to factor in the effect of the wind. i think it's a fair standard which brings both wind and temp into the equation .. i also plot the outdoor temperature on two different lines .. one if the NOAA 1-hr data and the other is my outdoor sensor -- located in the sun 1-min data .. i have placed it in the sun specifically b/c my house is in the sun. 

David Nadle

It's still a mistake

Wind has a lot to do with convective heat loss, but what drives heat transfer through your walls is conduction, and that is a function of Tinside - Toutside, Toutside being the actual temperature, not the windchill temperature. You aren't even correctiing for outdoor temperature or windchill temperature so I'm not sure what your point is.

I respect what you're trying to do but it's simply irresponsible to write things like "enclosures cost $200 a season" and so forth when you can't justify it. You're measuring a lot of stuff but there's no science behind your analysis.

jpf321

fair enough...

i agree that i'm probably not doing the data justice .. and am probably making assumptions and conclusions recklessly. i will refrain from extrapolating conclusions and simply post data of different things as I think to measure them. or use words like "enclosures *may* waste more money" and provide for everyone else the master dataset as I build it.



i will still try my best o make sense of what i see but my apologies if I was illogical in my analysis or made assumptions which I didn't fully understand. and I certainly welcome feedback about ways I can improve my methods so that it is more generally useful or informative overall. thanks David.

jpf321

but ..

is it not intriguing to find that on a warmer temps day (not the windchil, but actual) than the previous that the system ran longer with the enclosures? there must be some correlation, even if i am unable to understand how to quantify it. 

David Nadle

Enclosures

The simple explanation is that your enclosures reduce the total heat flux. It takes longer to get the amount of heat needed out. Runtimes might increase, but they also might occur less frequently if the enclosures increase system mass.



To quantify the effect you'll have to collect data over a longer period, refrain from making other material changes during that time, and control for heating degree days.