garn jr burn

[flyingcow]

Been a week or so since I fired up the jr.

This unit is in my truck garage, it's hooked up to one modine style type of unit heater.

Turned circulator on an hour before firing. Upon starting a fire, boiler was 68f.

Filled unit full and lit.

20 mins into burn tank was at 80f. At that time I plugged in unit heater. Unit not hooked up to t stat yet. Unit heater was pushing about 20k btu's.

40 mins into burn. Tank 100f. Unit heater pushing 31k btu's.

1h 40 mins into burn. Good sized pile of red hot coals but no wood left. Stack temp 330f. Winding down. Tank 133f. Unit heater pushing 56k btu's. Just put more wood in. Apx 1/3 of a load of wood. 12 mins after wood is in, stacks at 638f. Tank jumped up to 138f in that 12 mins.

A few notes. My wood is a yr old. Beech/rock maple stacked and drying for 12 months. I'll find the meter to get a mc.

Garage was only down to 45f. Obviously warmer now. About a 2300 sq/ft w/16ft ceiling garage.

Unit heater only works when I turn it on. No t stay yet.

Out side temps 24f.

Also, I have a solo in Nova with storage in my house. Love that unit also. Not advocating for either set up. Just goofing off on a sunday.

 

[leon]

Good Morning Flying Cow,

Your weather sounds like ours in New York.
Have you insulated your Garn yet??

From what I have read Garn recommends that
their units be insulated or an insulated room be
built around it.

With Stack temperatures like that I would give Gary Switzer
in Dundee, New York a call and ask him whether he could build a
scavenger for you. He made 4+ tube scavengers for his boilers and
furnaces that were either short or very long in length to strip the
heat from the boiler or furnaces flue gasses using a chimney
top induced draft fan but I would bet your forced draft fan could
do this for you with no issues.

 

[flyingcow]

I've got it loosely wrapped in f/g. Two layers.....temporarily......been going on two winters now. I tend to put things off.

 

[Karl_northwind]

It'd be interesting to see your tank stratification with that setup. a small unit heater like that will not stir the tank too much. we've got one that we set up to pump to mix for both filtering and breaking tank stratification. unfortunately with the JR, it's a lot of burner in a relatively small tank, and you can only fit so much heat exchange area in there. you can really see the difference between the 1500 and 2000. nearly identical only another 2 or 3 feet of length, which times five passes gives you 10 more feet of heat exchange area, and keeps the exhaust temps down.

I'd be curious with your truck garage, if you pulled off the insulation, and shut off the fan coil, how would the radiant loss off the boiler do for your heat load. I've hear anecdotally about people doing this, but nothing concrete.

 

[flyingcow]

It'd be interesting to see your tank stratification with that setup. a small unit heater like that will not stir the tank too much. we've got one that we set up to pump to mix for both filtering and breaking tank stratification. unfortunately with the JR, it's a lot of burner in a relatively small tank, and you can only fit so much heat exchange area in there. you can really see the difference between the 1500 and 2000. nearly identical only another 2 or 3 feet of length, which times five passes gives you 10 more feet of heat exchange area, and keeps the exhaust temps down.

I'd be curious with your truck garage, if you pulled off the insulation, and shut off the fan coil, how would the radiant loss off the boiler do for your heat load. I've hear anecdotally about people doing this, but nothing concrete.

for the first week or two after install, I did run it un-insulated. The unit was not directly in the big area of garage. Didn't work all that well.

 

[jebatty]

How did you determine the btus from the unit heater?

 

[woodsmaster]

do all garns run that high of a flue temp ?

 

[mike van]

do all garns run that high of a flue temp ?

Mine will usually be 520 to 550 for the first hour, dropping back after that. I have seen it over 600, but Its not something I hang around watching though -

 

[salecker]

I've got it loosely wrapped in f/g. Two layers.....temporarily......been going on two winters now. I tend to put things off.

There is nothing more permanent than a temporary solution.
One guy that lived near my mom and dads house was a hands on type of guy.His hands on left a lot to be desired.His saying was "good enough for now". They lived out of town till they couldn't manage on their own(no services out of town like power water sewer) then moved to town in a trailer.Then as their mental capabilities declined they had to move to a wrinkle ranch. Now both their house and trailer are uninhabitable,both didn't last long after they left.
In his case "good enough for now" served him perfectly.Their kids just took from them for years,which was sad because they never had much,and all the kids could have worked.
But in the end"good enough for now" was perfect for them,they left nothing of value behind.