Caddy install...Main blower cooling off heated wood furnace air?

[whankin2]

Hello all.
Again, I am getting ready to install my new 1950 (Caddy), and had another install question before I do. Last year, after screwing around w/ a Daka before selling it, I gave up on trying to solve my problem. Arrangement was that with the Daka, the small fan inside the wood furnace served to move the wood furnace heat output into the plenum of the main furnace(gas). When the main plenum heated up, the main furnace (gas) blower kicked on to supposedly distribute the heat t/o the house.

Problem is that the big gas blower really just cooled down the heated plenum air to such a point that basically only cool-lukewarm air came out my vents. It drove me crazy, & I want to get it right with this caddy, so any advice from laynes69 or any other install experts would be greatly appreciated. Is there some way of preventing this? BTW, my setup will be parallel, not series, and my 1950 comes with the fan inside the wood furnace.

 

[freeburn]

Just make sure your ductwork is large enough going into the warm air plenum otherwise you will lose precious CFM's. Your gas/oil furnace fan shouldn't need to run at all with the Caddy blower being larger than a DAKA and you should have dampers installed so that you don't get back blow. This is how a true parallel installation is supposed to work. In shor, the fan on the Caddy is sized so that you should get warm/hot air out of the ducts. And by all means, post pictures when you get finished and fired up!

 

[laynes69]

I have my furnace set to come on at 145 and off around 90. When I first start a fire, the blower will run on and off till it gets warmed up. Hours after the fire burns down, the fan will operate on and off with coals in it. I have my blower set at high. It may not seem too hot from the registers, but when the caddy needs to heat it will get much warmer and heat the home. There are 4 speeds on the blower, so whatever one works for you, and you may need to adjust your fan limit accordingly. My main duct is 8x18 and the furnace will push out some hot air from the registers when the furnace is cooking! Like said also a good backdraft damper will help the system alot.

 

[whankin2]

Well, so far so good w/ the install. We had a heckuva time getting it off the trailer and into the room. Once it was in, the install of the chimney pipe to the flue was no problem. To meet clearance requirements I decided to bring the Class A stainless pipe 2 ft further into the room, transitioning at a 90 to the stovepipe. By doing so, being 3 inches below the upper flooring is within the 2-inch requirement, vs the 6-in requirement w/ dbl-wall stovepipe. Next I will be bldg plenums for the 1950's cold air return outlet and the wood furnace heat outlet that will goto the main-furnace plenum. Stay tuned for further updates, esp as it regards backflow air prevention. Will try to send pics

 

[freeburn]

By the way, is this unit new? If so, where did you find one of these new?

 

[laynes69]

Unless you have a tall chimney, I would use 45 elbows for the connection of the furnace to the chimney. Also don't forget the barometric damper.

 

[whankin2]

Yes, I will be including the barometric damper. Any idea how that looks for a rectangular plenum as opposed to round ducting?
Also, FREEBURN, yes I did get this new. I sorta think I got lucky by on a whim contacting the same place laynes69 said he got his, and the store manager (Rural King in Wooster, OH) saying he just happened to have one in storage that he hadn't put on the floor yet for the season. Says it was his last one, but of course laynes69 thought the same when he got his, so you ever know. I do know however that US Stove does not distribute them anymore as the 1950, and you now have to goto PSG for the Caddy. Maybe one can get lucky like I did w/ a Hotblast from a store that has some left from last year.

 

[whankin2]

Well, it has taken me sometime due to work schedule and holiday prep, but I am finally burning a little bit with my new Hotblast 1950 (Caddy). I have only placed a few logs in so far, and that was early last week. I do suspect that I will really ramp things up with good burns this week, as the temps are supposed to dip with snow by Thursday, if not tonight. As you may or may not be able to see from the pics, I ran plenums to both my main return and to my main heat trunkline. I would have placed it into the main gas furnace plenum, but clearances with other stuff got in the way. For the time being, I went with manual dampers in both my return and heat outlet with the plan to eventually put motors on them for automation as I tweak and experiment with most ideal settings. By Wednesday I plan to complete electrical hookup of the thermostat to the wood furnace damper servo-motor that sits on front of furnace. Currently I just open accordingly for the fireburn and loop chain to secure. As you may also see, I even was able to procure some really dry wood from a dead ash that had been standing bare for few years across my land. Can't wait to get home and seriously crank up the heat to see the heat output and burn time. I will report back later this week. In meantime, big-time thanks to Laynes for all of his assistance, as well as others here. This forum is invaluable, esp considering that the manual is pretty poor.

 

[laynes69]

Awesome! It will take some time to get to learn the operation of the furnace. Nice clean looking install. Congrats!

 

[Gary_602z]

Stihl 026? Looks like dead elm!

Gary

 

[whankin2]

036 saw - borrowed from neighbor. Worked great!

Ok, after firing up my new 1950 (Caddy) here a few times, my take on things are positive overall, but also a little mixed with a few concerns. I very much like being able to visually see the burning flames with the glass; I am also impressed with the radiant heat that the glass puts off. Smoke creation is hardly a factor so it seems like it is effective for preventing creosote buildup. This is clearly a very sturdy unit.
But if I could walk down my concern list, I hope there may be some suggestions.

1) I have my blower on high, but the airflow for the registers at the end of my house runs seem to be much weaker than when my regular furnace runs. The registers closest to the wood furnace are much stronger with airflow. It is a multi-speed blower and I have it at the highest setting. I am wondering if I should consider some small duct fans

2) The heat coming out of my registers seem to not be as hot as they could be, esp. when the heat buildup in the plenum of my woodfurnace seems to be fairly hot/warm. The air coming out can almost be called cool, even though the woodfurnace has a raging fire. Does this have anything to do with what I am hearing called "static pressure"? I even wonder if I should change the settings at which my blower comes on and goes off.

3) I have a thermometer with a probe into my dbl-wall black stove pipe, the highest reading I seem to get is about 390, when the recommended temp reading is 400-600. Is this indicating a problem with my system?

4) Wood seems to burn faster than it should; I am using very dry wood, but even when I close the draft on the front, wood burns somewhat fast. Maybe my splits are too small…not sure. Granted, I do like seeing the fire, but it still seems like a fast burn. My thermostat will eventually control that draft door on the front, but until I hook that up, I am manually opening and closing the draft opening as needed.

Any thoughts or ideas are greatly appreciated, and I will share any info I have to hopefully help someone else out in these forums with as much assistance as I have gained from everyone's input.

 

[laynes69]

There is a recommendation on static pressure in the manual. If your pressure is off, so can your airflow and heat be. You have a damper in the central furnace to stop the pressure from backfeeding right? Heat at the end of the duct runs won't be as hot as the closest ducts to the furnace. If your blower is coming on and off too quick then you should adjust the settings on the limit control. You'll have to play with it some to get the setting you personally need. For me its 150 on and 100 off. The furnace does a good job at extracting heat from the fire. Stack temps will run low and 390 is fine. With the furnace burning as clean as it does, you don't have to worry about so much creasote in the flue pipe. You will occaisonally have to scrape the heat exchanger out, but it takes just a minute or 2. As far as the burn times, once the wood load is charred and the secondaries are kicking in, you can close the damper. I manually override our damper with each load that I place in the furnace. Larger pieces and tighter loads will burn longer, as well as more dense woods. When your limit is set right with the temps, then you can get alot of heat from just coals. Remember the heat might not be as hot as the central furnace. But its constantly pumping a steady heat in the home requireing less btus this way and more comfort. It will take some time to get used to. When the btus are then needed, it will pump out the heat. Did you set your barometric damper yet? And running the furnace with the damper open will put more heat out the chimney. With the thermostat on the damper motor, the damper only opens maybe a 1/2 inch when it calls for heat.

 

[whankin2]

Well, I have been able to play with the limit settings, as well as loading up bigger, rounder hardwood at night, and I am seeing some improvement. I also failed to initially install the barometric damper on my fluepipe, and so will look to do that soon to see if further improvement is seen. As for the furnace damper, I have not been able to figure out the schematic for wiring the servo-motor to thermostat to transformer, and so I have been operating that manually. Laynes or anyone else w/ the Caddy, if you are also using red/white thermostat wiring, could you provide further detail about the connections you have, especially w/ the blade contacts on the transformer. The manual again is not very clear at all for a non-electrician, but I do think I am good enough to be dangerous. Even a photo would be helpful, and thanks in advance.

 

[lexybird]

Whankin what kind of burn times are you getting out of a full load of hardwood ?what ambient room temperature is it maintaining in the house

 

[laynes69]

I'll tell you what I did. I used 2- 2wire thermostat wires. On my thermostat, which I changed is a digital. You need a milivolt thermostat, or the one that came with it. The wire thats for the thermostat, has red and white. Red is on RH with the jumper on RC and white is on W. Red goes to one side of the transformer. I then wired a second wire with red and white wires going from the transformer to the servo motor. White is on the yellow on the servo, and my red on the orange wire of the servo which goes to the other side of the transformer. The 2 whites then are wire nutted together at the transformer. So follow this, but use just change the wire colors accordingly to what your have.

 

[Lawnman323]

I finally fired my Caddy before Thanksgiving for a day and have some of the same lukewarm temps coming out of the vents as discussed above. My ducts are 10x20. The technician moved the fan limiter switch to the middle of the front and it seems to be functioning better there, has anyone else done this? I understand the more consistent heat principle. I also don't have a barometric damper installed, what exactly does this do?

My question is this: When the blower kicks on, heat POURS out of the damper door. I mean POURS. Like burn your hand pours. This does not seem right, especially when I am getting lukewarm air from the vents. My fan setting is on medium I believe, high kicked the fan limiter on/off too much. You can barely feel the air coming out the vents when it is on low.

Any help would be appreciated, I will post pics & start a thread on my install when I have a minute. I keep telling myself that this furnace will be worth it, I just need to learn its personality.

 

[laynes69]

There is some leakage around the front of the unit, but not too much. It has a 2 layer front to help hold the heat in the furnace. I have my blower set one speed down from the top, and I moved my limit control to the front of the unit like you did. Having a baro installed does 2 things, one slows down the draft to a set point, and two it helps more heat be removed from the furnace. If the draft is too high, then you are sending heat out the chimney. You want to set your limit control to a point where it will remove as much heat from the furnace as possible.

 

[whankin2]

Sorry for the delay, I have been away. As an update, the past week I have been getting 7+ hr burn time. So, I have been loading it up before bed bout 11pm, coming back upon wakeup in the morning to have pretty decent burning woodcoals in the morning about 6:15. This after basically setting it to where the damper is essentially closed since I don't like to get to hot while sleeping. The temp on the thermostat hooked up to my gas furnace has been reading 70, but it actually feels warmer than that, and we're talking last week when it got pretty darn cold. Now, one thing I had to do was balance out my system between the main level and my basement level, where I also have several registers. Since we don't spend much time down there during winter, I went thru and closed the dampers on about 7 runs from my trunk line that lead to the basement. Even if I do need heat down there, we have a gas fireplace during those rare times that can be used. Closing off these runs seemed to dramatically increase the airflow thru the registers of my main floor (1800+ sqft), which seemed to lead to better warming of our main living area and bedrooms. I think our house w/ the finiished basement was just too big for the caddy, but it seems fine for Winter living area we need. So, I think increasing this pressure via closed registers may have helped w/ heat output, and I still may try a barometric damper at some point for even longer burn times if that would help. May wait until next year.

 

[whankin2]

Also, Thanks laynes for the wiring help, greatly appreciated. Lawnman, I do not know going on w/ your pouring smoke, but one thing that I got, and that the wife appreciated, was the usage of some welding gloves for wood loading. They seem to work much better against heat than the piddly work gloves scooped up from Lowes. Even helped w/ convincing the wife to get into the woodloading game

 

[laynes69]

We are getting better with our furnace, for it will take some time to get used to. Long burn times ain't a problem at all. Glad your getting it worked out, and it will continue to get better.

 

[Lawnman323]

Also, Thanks laynes for the wiring help, greatly appreciated. Lawnman, I do not know going on w/ your pouring smoke, but one thing that I got, and that the wife appreciated, was the usage of some welding gloves for wood loading. They seem to work much better against heat than the piddly work gloves scooped up from Lowes. Even helped w/ convincing the wife to get into the woodloading game

It's not smoke, it's hot air - that should be going up through the plenum. Still unsure on this. Will be firing it next Monday, we will see. I'll start my thread then. Laynes, did you get my PM?

 

[Lawnman323]

Caddy cautions you to "keep an open area near the top of the firebox to maximize heat". How are you guys loading your furnaces? Stacking all the way up, half etc.? All parallel logs, H-pattern, etc? I know how to build a fire, but don't know how the "Caddy likes its fire built" haha.

Concerning ashes, do you leave the charred embers in there or take them out? Do you use the ash door or just shovel the ashes out? The ash door seems mickey-mouse to me. Are you cleaning the ashes every time you load? Any front to back logic?

Sorry for the multiple questions, I don't want to be cursing at that damn furnace next Monday.

Thank you again for all your help, I will keep you posted.

 

[laynes69]

Oh you'll curse it im sure. You will learn how to control it. It depends on the weather on how you load them. You can fill them up and leave a few inches for the tubes. Let the furnace get hot and you will see seconary combustion then you can shut the damper the furnace and let it do its thing. We only load north south and larger splits burn longer. Each morning we shovel some ash out of the furnace. We always rake the coals forward then load the furnace. It will burn front to back.

 

[Lawnman323]

I fired it a few nights ago, smoked me out again. Followed the instruction manual to a "T". Can I install a draft inducer similar to this? (broken link removed to http://www.northlineexpress.com/itemdesc.asp?ic=5TJ-AD-1) I'd just use it to get the unit heated up.

I need to be able to start this up/shut it down quickly. I will burn for 2 weeks, leave for a few days, come back, burn for 3 weeks, leave for a week, etc. That is my schedule in the winter.

Getting this Caddy going when stone cold without smoking out the place is proving to be a chore. This is a long term problem that I need to figure out now.

Any thoughts?

 

[laynes69]

We had it happen once when the weather was warm and there was little draft. Have you tried top down fires with some newspaper knots on top and some kindling below that? It gets a roaring fire quickly and warms up the chimney. What type and how tall is your chimney? If needing worse case is operning the front heat exchanger and using a hairdryer or something like that on the center pipe to help heat make a draw so you can get the unit going. Try the top down, and crack the door slightly and it may help you. Use smaller wood until your coal bed is established then load the unit up.