Harbor Freight 10 x 12 Greenhouse Build - Page 7 - Orchid Board

shadytrake · #61 11-01-2014, 12:18 AM

Fired up the RMH today and it works GREAT!! Right now it is 44F outside and the GH is 58F with humidity at 75%. We are running it pretty low so that we don't cook anything at night. We have a 12QT pot on the barrel filled 3/4 with water and it is steaming away.

The top of the RMH barrel is 300F. Hoping that the thermal mass is storing the heat. Going to set the alarm clock to check it every 2 hours tonight just to make sure since it is dropping to 33F.

Looking forward to a LOT lower utility bills this winter.

Cntry · #62 11-01-2014, 12:42 PM

So how did it go last night did everything stay toasty warm in the green house? I bet you need a nap today being up every 2 hours.

shadytrake · #63 11-01-2014, 05:17 PM

Hubby had to get up 3 times to restock the fire with wood, and it is running as well as expected with some of the green wood. We didn't have a lot of time to be picky and we got as much dry wood as possible. Today we will split some of the larger logs to find the cured wood.

I got up at 5:45 this am and went out to check it. Embers were still burning and the mass was about 65F (not too bad for a cold night on the first run). The backup heater had kicked on and the GH temp was 55F. I stoked the fire and put some 2x4 pine in it to really kick it on.

The main chore today was to go back to that neighborhood stack and score a bunch of kindling. That is what really starts it fast. Newspaper is good, but the best starter is dried kindling. I would give this first "real world" test a B. The mass really needed to be warmer so that the RMH will draw faster. But that can only come with burning and priming and we can't burn it when it is warm outside.

And that is what we did all day today. Got the barrel to 560F and the thermal mass is reading 84F on the east side and 72F on the west side. We are burning it as hot as we dare to build up the thermal mass heat for tonight. Hubby just went to restock the feed tube to bring the barrel temps back up to at least 400F. That seems to be the optimum heat for thermal mass storage without drying out the orchids.

I also had to go through and mist everything so that I can keep the humidity up. Readings right now 74F and 75% humidity. Outdoor temperature 49F and dropping as the sun goes down.

Until the rest of the orchids finish blooming, we want to keep the GH fairly intermediate. After that, we will let everything gradually go dormant as needed.

shadytrake · #64 11-02-2014, 08:12 AM

I give last night's test an A! Paul only had to restock the feed tube twice and I got up at 5:45am to check temps and the GH was at 55F. I went out to restock it at 6am and the backup electric heater came on as I was lighting the wood. YAY! A whole night of electricity SAVED!

Thermal mass was WARM at 90F so it was helping the ambient temperature to remain steady. AND the humidity is 62% and rising because of the condensation on the panels. I checked the drip points and they are dripping right into the walkways with only a couple of points hitting orchid leaves. SUCCESS!!

sweetjblue · #65 11-02-2014, 08:47 AM

Now all you have to do is figure out a way to autofeed so neither of you have to get up in the middle of the night.

Judi

Cntry · #66 11-02-2014, 06:09 PM

It sounds like it was a success for sure. I am happy for you both. I agree with Sweet you need a auto feed so you both don't have to get up through out the nights ahead.

slc · #67 11-03-2014, 12:07 AM

Thanks for taking the time and effort to record your project and share it. It is very interesting and I look forward to your reports through the winter.

shadytrake · #68 11-03-2014, 08:15 AM

Did not have to restock the last night. So it seems if the temperature remains in the 40s, the thermal mass can handle the ambient temperature as long as the mass is at 90 at 10pm. I just checked temp at 6:15 and it is 54F and the electric heater has kicked on. We slept through the night only waking up a couple of times to check the readout by the bed. What I need to get is a low temp alarm to send a signal to my phone. That is on the want list.

shadytrake · #69 11-06-2014, 03:10 PM

So an update on the Rocket Mass Heater for the greenhouse. Today is ash cleanout day. You can see that the efficiency of the burn creates very little ash. Awesome!

shadytrake · #70 11-13-2014, 09:20 AM

An update on the GH and RMH since we have had the arctic blast deliver winter early this year (we got a dusting of snow). Compared 2 months of utility bills and we have saved $98 over last year already AND we are averaging about 5-10 degrees cooler this year.

We did invest in 2 x 40lb bags of pellets because the embers burn longer so re-stoking is much quicker and easier. Cost $11.

We went on a wood hunt yesterday and found a load of discarded indoor framing from a house remodel. That is the BEST wood. It is already dry and it lights FAST. Another trick we learned is that if we place the cut wood on top of the thermal mass, it keeps the wood nice and dry (even with our misting) and the wood helps to distribute the heat from below.

Also, last night we went to the Tigers game so we were gone for 4 hours (it went to overtime). We stoked the fire and departed at 5:45 (temp at 43) and returned home at 9:45 (temp 35). Over that time, the GH temp went from 63 to 54 and the electric back up kicked on right as I opened the door to restart the fire. So we really know the thermal mass is working.