Caddy or Max Caddy temporary installation

[David_QC]

First post here, and please forgive my bad english :- )
I have a 1977 one story and a half house of 48 x 32 (interior 46x30), I live in Quebec so having -25 to -30 celcius is common. The living room has a cathedral ceilling with what we call a Mezzanine in french (can't find translation!)
Basement is not insulated.
Windows are all original 1977
Existing oil furnace is 85,000 BTU which have hard time to keep up a 20 celcius inside when at -30 outside (but it does, running almost constantly)
Now I want to choose between a Caddy or a Max Caddy... and that's why I ask for help.
Would you choose the Caddy or the Max Caddy ?

And for now I want to install it temporary in the basement without connecting it to the existing oil furnace duct, as i'm running low on money, I want to save some money on the duct work and the electric heater installation in the furnace, I will do it next winter.

Just below where I will install the furnace, there is a 3' by 1' massive metal hole plate in which I will align the output plenum.
My second question is; is it safe or a bad idea ? will it work ?
Is it easy to not output too much heat ? like a lower fan speed with less wood ?

 

[heatingcostssuck]

Find out if a Drolet Tundra costs less in your area, also whether or not they can be used as an "add-on" furnace. Maybe the cost difference would allow a proper install.

My guess is that it wouldn't likely be safe, or at least unhealthy.

 

[David_QC]

Just an update of my temporary installation;

I have finally choose the Max Caddy.
For now, it is installed near the existing oil furnace but it is not connected to my house duct.

It have a Hot air plenum as per manual drawing, but for now I have 2 x 8 inch round output going to both end of the house, and 2 x 4 inch for the basement.
I have no cold air plenum, only the filter.

Static pressure at the hot air plenum is 0.3 at the first speed and maybe around 0.4 full speed
Draft is at 0.06, with a few washer on the weight !
My chimney is 8 inch diameter about 30 ft height, but I will use 6 inch insulated SS liner when I will move the furnace to it's final place.

I run it at Manuel mode with Fan level 1 and KIP at 132F, it never reach the best effiency zone of 165F, at best it will reach 150F for an hour and then will cycle On/Off for the rest of the burning time.

Chimney temperature is in the beginning of the burning zone and go up to the middle of this zone at damper full open.

My burn time is about half as stated, maybe 4 hours before the fan will not start again, but I can't really complaint, basement air is usually 60 to 65F which freeze the furnace really fast, my wood ( 1 year Maple) is a bit wet, the meter says between 15 to 20% but the secondary flame quit early when the damper close, and the window doesn't clean itself.

Next investement for this summer is the chimney liner and a few duct work... I hope it will perform as it supposed to next winter.

 

[Wisneaky]

Just an update of my temporary installation;

I have finally choose the Max Caddy.
For now, it is installed near the existing oil furnace but it is not connected to my house duct.

It have a Hot air plenum as per manual drawing, but for now I have 2 x 8 inch round output going to both end of the house, and 2 x 4 inch for the basement.
I have no cold air plenum, only the filter.

Static pressure at the hot air plenum is 0.3 at the first speed and maybe around 0.4 full speed
Draft is at 0.06, with a few washer on the weight !
My chimney is 8 inch diameter about 30 ft height, but I will use 6 inch insulated SS liner when I will move the furnace to it's final place.

I run it at Manuel mode with Fan level 1 and KIP at 132F, it never reach the best effiency zone of 165F, at best it will reach 150F for an hour and then will cycle On/Off for the rest of the burning time.

Chimney temperature is in the beginning of the burning zone and go up to the middle of this zone at damper full open.

My burn time is about half as stated, maybe 4 hours before the fan will not start again, but I can't really complaint, basement air is usually 60 to 65F which freeze the furnace really fast, my wood ( 1 year Maple) is a bit wet, the meter says between 15 to 20% but the secondary flame quit early when the damper close, and the window doesn't clean itself.

Next investement for this summer is the chimney liner and a few duct work... I hope it will perform as it supposed to next winter.

Take the washers off the baro and increase the draft a little. Your smothering the fire too much if it isn't cleaning the glass and also the reason your plenum isn't getting up to temp. The -.06 inH2o is an average so it will go higher than that when the front damper is open.

 

[brenndatomu]

my wood ( 1 year Maple) is a bit wet, the meter says between 15 to 20% but the secondary flame quit early when the damper close, and the window doesn't clean itself.

Are you testing the wood on a fresh split face? Secondarys going away and dirty window says wet wood...you'll be much happier with this unit on 2 or 3 year dried wood

 

[David_QC]

I will try on a fresh split next time and I will post some picture or video
I will buy wood for 2 years this season and I will ask for it to be split in smaller pieces, if i'm lucky it will be dry next winter and in 2 years I will start having some good dry wood...

 

[JRHAWK9]

What's the deal with some of these crazy high recommended plenum temps I've been reading about on some of these furnaces? My -LP- furnace plenum temps hardly ever reach 120°. My furnace came with a low limit switch set to 105° on, 85° off. My plenum temps mid burn (which lasts for ~60-75% of the burn cycle) usually range from 98° to 110° depending where I have the dial on the computer set at and normally the blower doesn't shut off until I have a couple handful of coals left.....regardless of computer setting I just find it interesting at how hot they want the plenum to be and don't understand/know the reasons why. I'd think with wanting to keep the plenum 150°+ the blower would be cycling on/off quite a bit in order to maintain those temps.

 

[Wisneaky]

What's the deal with some of these crazy high recommended plenum temps I've been reading about on some of these furnaces? My -LP- furnace plenum temps hardly ever reach 120°. My furnace came with a low limit switch set to 105° on, 85° off. My plenum temps mid burn (which lasts for ~60-75% of the burn cycle) usually range from 98° to 110° depending where I have the dial on the computer set at and normally the blower doesn't shut off until I have a couple handful of coals left.....regardless of computer setting I just find it interesting at how hot they want the plenum to be and don't understand/know the reasons why. I'd think with wanting to keep the plenum 150°+ the blower would be cycling on/off quite a bit in order to maintain those temps.

Plenum temps in a wood furnace only stay that hot for a few minutes. Once the blower kicks on they drop off real fast. It takes 5 minutes plus to go from 90 degrees to 175 degrees and once blower kicks on temps fall back to 90 in a matter of minutes.

 

[JRHAWK9]

Plenum temps in a wood furnace only stay that hot for a few minutes. Once the blower kicks on they drop off real fast. It takes 5 minutes plus to go from 90 degrees to 175 degrees and once blower kicks on temps fall back to 90 in a matter of minutes.

Yeah, I understand that, but then why would one want the low limit set so high? The blower would be constantly kicking in/out and would probably be off more than on. One would think you'd extract more BTU's out of the furnace if the low limit was set lower so the blower stays on longer. Like I said above, my blower pretty much runs constantly over the entire burn cycle and gives off consistent heat instead of uneven non-consistent heat you'd get with the low limit set so high..

 

[brenndatomu]

I just find it interesting at how hot they want the plenum to be and don't understand/know the reasons why.

Well, on non Kuuma furnaces, you have to worry about creosote, lower plenum temps increase creosote production. That's what I was tolt...
You hafta realize, your experience with a Kuuma is not typical of all us peasants with the more common heaters of mere mortals

 

[JRHAWK9]

Well, on non Kuuma furnaces, you have to worry about creosote, lower plenum temps increase creosote production. That's what I was tolt...
You hafta realize, your experience with a Kuuma is not typical of all us peasants with the more common heaters of mere mortals

LOL..... Has anyone confirmed this to be the case though? I know our house would not do well without having constant heat. As soon as the blower shuts off it seems like my thermostat acts more like a countdown timer than a temperature gauge

 

[brenndatomu]

As soon as the blower shuts off it seems like my thermostat acts more like a countdown timer than a temperature gauge

Has anyone confirmed this to be the case though

Well, that came from a Yukon employee so...

 

[Wisneaky]

Yeah, I understand that, but then why would one want the low limit set so high? The blower would be constantly kicking in/out and would probably be off more than on. One would think you'd extract more BTU's out of the furnace if the low limit was set lower so the blower stays on longer. Like I said above, my blower pretty much runs constantly over the entire burn cycle and gives off consistent heat instead of uneven non-consistent heat you'd get with the low limit set so high..

I don't know much about the Kuuma, but does it have an actual probe in the plenum to take plenum temperature? My tundra fan snap disc is I believe 135 degrees on and 115 degrees it shuts off, but that isn't actual plenum temps. Actual temps are 175 on sometimes even higher and about 90 off and I measure those temps with a digital probe thermometer.

 

[brenndatomu]

I don't know much about the Kuuma, but does it have an actual probe in the plenum to take plenum temperature?

The VF 100 has a fairly standard furnace fan control/limit switch

 

[JRHAWK9]

I don't know much about the Kuuma, but does it have an actual probe in the plenum to take plenum temperature? My tundra fan snap disc is I believe 135 degrees on and 115 degrees it shuts off, but that isn't actual plenum temps. Actual temps are 175 on sometimes even higher and about 90 off and I measure those temps with a digital probe thermometer.

No, there's no temp probe. It has a thermocouple in the firebox to keep track of combustion temps and this is connected to the computer which determines the correct amount of primary air to let in based upon the level of burn the user has set in order to precisely regulate the burn. I have my own HVAC thermometer stuck in the center of the plenum though, 31" above the top of the furnace. Keep in mind, the plenum is 24"x24"x39" tall. It's a big box. The low limit switch (snap disk) is on top of the plenum, so about 39" above the top of the furnace. I have my snap disk set at 105° on/85° off. It comes on when my temp probe reads 130°-140° and off when it reads 85°.

 

[STIHLY DAN]

I don't know much about the Kuuma, but does it have an actual probe in the plenum to take plenum temperature? My tundra fan snap disc is I believe 135 degrees on and 115 degrees it shuts off, but that isn't actual plenum temps. Actual temps are 175 on sometimes even higher and about 90 off and I measure those temps with a digital probe thermometer.

Yes it does. It has a stack switch and a snap disc, plus the firebox thermo couple. Sorry JR, had to make the correction.,

 

[JRHAWK9]

Yes it does. It has a stack switch and a snap disc, plus the firebox thermo couple. Sorry JR, had to make the correction.,

I guess it technically does, but AFAIK it's sole purpose is a high limit switch. It doesn't supply feedback or do anything unless the high temp limit trips it and then it sends the blower on high.

 

[David_QC]

Are you testing the wood on a fresh split face?

You are right, wood moisture content inside is more 20% to 25% inside

Take the washers off the baro and increase the draft a little.

I tried it yesterday, yes it does increase secondary flames and heat output, but with damper full open I approach the red zone at the chimney meter... draft is 0.08 without washer and damper full open

I have cut the chain link that open the damper and I installed a 10-32 2" bolt between both links, now I can control the damper opening by screwing the nut, so I reduced the opening maybe half way to full open and it seems to get a good results between no secondary flames at all (damper close) and too much heat out the chimney (damper full open)... but still no 8 hours or more burn time...
Here i'm only discussing, I know my "no return plenum in a cold basement", "no 6 inch liner" and "moist wood" doesn't help my case... I do add some dry palett wood and one eco-burn log to each of my filling, which help a lot !

 

[Wisneaky]

You shouldn't be messing with that front damper at all. Once secondaries start they should go for a long time. They just don't start and stop. -.08 with front damper fully open?

 

[David_QC]

Temporary Setup, I will remove oil furnace and connect the caddy to the house duct

Chimey setup... and cold start of a fire


My Old wood stove that I replace... temp plenum during the cold loading

Fire after loading it... chimney temp is after 20 minutes of full damper open, plenum temp was standing still at 145F degree, burn time was about 3-4 hours with that load.



Manometer with damper full open after 20 minutes of open damper, it goes back to 0.8 at damper close

... I think i will at least add one washer to the baro... 4 washer = 0.06

 

[David_QC]

This picture is probably the most revelant...



It's a fresh split maple, one year dry, meter read between 20 and 25

 

[JRHAWK9]

This picture is probably the most revelant...

View attachment 155286

It's a fresh split maple, one year dry, meter read between 20 and 25

What model/brand meter is that?

 

[David_QC]

MasterCraft... brand of Canadian Tire

 

[brenndatomu]

Manometer with damper full open after 20 minutes of open damper, it goes back to 0.8 at damper close
... I think i will at least add one washer to the baro... 4 washer = 0.06

The wet wood is limiting the heat output which keeps the damper open longer which keeps the draft high...it's a vicious circle. If you can get the 'stat satified long enough to let the damper close your burn times will sky rocket.
Why do you need to add washers to the baro? Is the sliding weight not enough? I have never seen a situation where weight had to be added to lower the draft unless there was creosote buildup on the back of the baro flapper door, or if the flapper was binding for some reason.

 

[JRHAWK9]

Why do you need to add washers to the baro? Is the sliding weight not enough? I have never seen a situation where weight had to be added to lower the draft unless there was creosote buildup on the back of the baro flapper door, or if the flapper was binding for some reason.

I have to add weight to mine. I have 36' vertical to the top of my chimney. Daryl (Kuuma) told me about a guy in Chicago who had a 45' chimney who actually added TWO BD's in order to get his draft within spec!