PSG CADDY Owners

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justanothercub

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Aug 17, 2012
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As some of you know, I am moving from my home ( with wood boiler and 350 gal of storage ) to a new home that has a oil/air furnace. If I go with a wood furnace I will be buying a PSG Caddy and down the road purchasing the oil burner add on.

So what I would like to know is -
  • Size of your home
  • % of your home that is insulated
  • how many full or face cord of wood you consume a winter
  • how many times a day do you fire up
  • how warm do you maintain your home.

Thanks
 
As some of you know, I am moving from my home ( with wood boiler and 350 gal of storage ) to a new home that has a oil/air furnace. If I go with a wood furnace I will be buying a PSG Caddy and down the road purchasing the oil burner add on.

So what I would like to know is -
  • Size of your home
  • % of your home that is insulated
  • how many full or face cord of wood you consume a winter
  • how many times a day do you fire up
  • how warm do you maintain your home.
Thanks

I was looking at the Caddy too. A friend of mine has the add-on caddy and loves it. He has a larger well insulated house and uses about 8 face cord a year. He has a gas furnace for back up. I think he keeps the house around 20c.
I am leaning towards the Napoleon HMF150 furnace and like you fitting the oil burner later. Both furnaces appear to have similar burning systems. I have a Napoleon supplier near by, made my decision.
 
I was looking at the Caddy too. A friend of mine has the add-on caddy and loves it. He has a larger well insulated house and uses about 8 face cord a year. He has a gas furnace for back up. I think he keeps the house around 20c.
I am leaning towards the Napoleon HMF150 furnace and like you fitting the oil burner later. Both furnaces appear to have similar burning systems. I have a Napoleon supplier near by, made my decision.

I spoke with a place near by that sells both Napoleon and Caddy and there both within $100 of each other and the guy said the Caddy was built much better. just something to keep in mind. But having a dealer close by when something happens is priceless.
 
In our current 1863 2800sqf farm house with a tarm mb solo 150 with 350 gal storage that is insulated in places and rather drafty I can add logs to coals at 6 am leave for work and when I or my wife get home around 5pm, add some small wood ( coals are really getting low ) then around 9pm load it up full it will last until 6am. If the Caddy will last 12hrs with an empty home ( everyone gone doors never get opened in that time 8am-5pm ) then the caddy will work.
 
We heat a 2400 sq ft Victorian with 10' ceilings down and up. Our house is mid 19th century. Well insulated, but needs attention to some airsealing yet to be done. Last year we burned around 5 cord, but a little over a cord was slabwood and another cord and a half was half punky. My wife keeps the thermostat set at 75 in the winter. We rarely fill the firebox unless it's very cold out or overnight in colder weather. In the 30's a half firebox will last all night 9:30-5:00am. It's impossible to tell you how long the burns will be due to the thermostat setting and condition of the home (insulation, air leakage). The greater demand for heat, the lower the burn. I do know when it's cold no matter how long the damper remains open overnight for a call of heat, there's coals in the morning. We have never woke to a cold furnace. How many square feet is your new home, and where are you located? It sounds if the home is larger and little insulation I would go with the max caddy.
 
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Just a couple things to think about with a solid fuel warm air unit. Most codes require a 2"' or more gap between the duck work and the ceiling for about 10 feet from furnace and then it is reduced to a lesser amount of clearance. Pre-existing duct work never has this clearance as it was installed with gas ,oil, propane in mind which do not require these clearances. Your hot water heat was also exempt from this. The second item is if you are planing on central air you will need a auto damper or at least a manual one to isolate the AC coil from the higher heat out put of the solid fuel unit and bypass duct work to tie back in The AC coils are not made robust enough withstand the possible temps involved. These two items are never spoken about by the furnace mfgs. You will need to add duct work with filter for the cold air return to the wood furnace. Even the adds for the wood-coal/oil-gas all in one units fail to mention anything about this, but it is code ( national ) and your ins could have a problem with it.
 
We heat a 2400 sq ft Victorian with 10' ceilings down and up. Our house is mid 19th century. Well insulated, but needs attention to some airsealing yet to be done. Last year we burned around 5 cord, but a little over a cord was slabwood and another cord and a half was half punky. My wife keeps the thermostat set at 75 in the winter. We rarely fill the firebox unless it's very cold out or overnight in colder weather. In the 30's a half firebox will last all night 9:30-5:00am. It's impossible to tell you how long the burns will be due to the thermostat setting and condition of the home (insulation, air leakage). The greater demand for heat, the lower the burn. I do know when it's cold no matter how long the damper remains open overnight for a call of heat, there's coals in the morning. We have never woke to a cold furnace. How many square feet is your new home, and where are you located? It sounds if the home is larger and little insulation I would go with the max caddy.

We are moving from a 2800sqf home to a 2100sqf home. The new place if by far better insulated then our current home. We are located in upstate NY north of Syracuse by an hour. Our average winter temp between jan 1 to march 30 is 18-25F. The current oil furnace is a 98k btu furnace.
 
Just a couple things to think about with a solid fuel warm air unit. Most codes require a 2"' or more gap between the duck work and the ceiling for about 10 feet from furnace and then it is reduced to a lesser amount of clearance. Pre-existing duct work never has this clearance as it was installed with gas ,oil, propane in mind which do not require these clearances. Your hot water heat was also exempt from this. The second item is if you are planing on central air you will need a auto damper or at least a manual one to isolate the AC coil from the higher heat out put of the solid fuel unit and bypass duct work to tie back in The AC coils are not made robust enough withstand the possible temps involved. These two items are never spoken about by the furnace mfgs. You will need to add duct work with filter for the cold air return to the wood furnace. Even the adds for the wood-coal/oil-gas all in one units fail to mention anything about this, but it is code ( national ) and your ins could have a problem with it.


That is somthing that I will look into. The gap is significantly reduced if the surface is a NON combustible. No plans for central air, we only use a window unit for a couple months in the summer just to keep our bedroom cool at night.
 
The Max Caddy is a fantastic unit. It will do what the manual claims it will do. The Max Caddy is a well built, quality furnace. Electrical back up is also available. A added bonus is that PSG is a excellent company to deal with should any issues arise. As with any heating appliance, proper installation, set up and quality fuel would be the key to ensuring homeowner satisfaction.
 
If your new home is insulated, and fairly tight you shouldn't have any problem a Caddy. The Max Caddy would probably work, but might be a little too much. They changed the design this year for options like a blower, outside air kit, etc. A series install would save some money not needing a blower if your central furnace is in good shape. They have changed a bit since ours was purchased.
 
im trying to find a cut away picture of the Caddy. Google and PSG dont seem to have one. Has anyone seen a picture like that? Also is the Caddy a true gassification furnace or just a really clean burning wood furnace??
 
Standard Caddy here, going into our fourth winter with it. Big old farmhouse about 2500 sq ft. Poorly insulated but have replaced most windows and doors. Didn't even have ductwork to upstairs, so we added it up and through the attic ... less than ideal. And cold air return from upstairs is only through a floor grate and down stairway. Caddy runs parallel to a high-efficiency propane ... cold air through a 6" filter then splits to two furnaces, plenums rejoin, louvers just after the Caddy to keep A/C air from running backwards through Caddy too much. Can't tell you how much wood I burn because I don't count it. Just cut it and pile it up. Sometimes oak sometimes box elder and everything in between. Also winters have been very variable, and I can't get my wife to keep her paws off the gas thermostat to give the wood a chance to burn. But I'd say 6--8 full size pickup box loads square to the top of the cap in the worst winter here on the Minnesota/Iowa border, and that before we changed out original rattletrap windows and put a garage on the north side.

I sketched some cutaways because the flows through this thing are complex.
caddysidecutaway.png

caddytopfirebox.png

caddytopexchanger.png


The box is lined with firebrick on four surfaces. No brick on the door side of course, and none on the top. The top is a stainless baffle with fiberglass insulation on top of it, then the steel top of the box above. There is a tiny metal plate about 2"x6" over a grate in the floor where you are supposed to shove ashes down into the ash box. It's a hassle, so I cut the tiny grab loop off it and I just leave it alone. I shovel ashes out of the box itself. I also discovered the coals don't burn all that well on the bottom of the box, so I laid a cast grate from another old woodburner in the box. It's just long enough to rest inside the door with a gap under it at the front but not at the back. The front of the box has a tiny hole to let air in for the coals when the draft is closed.

Airflow through the drafts is complex and some of this is guesswork:
- Main intake, controlled by thermostat (no fan) is above the firebox door. Behind it are three intakes. There is a hole in the center of the door that lets air into the center channel even when it is closed.
- There is also the tiny jet I mentioned below the door.
- And there are two square intakes about an inch square below the bottom corners of the firebox door that are always open.
Inside the box, two big steel channels go up the back of the box and then across the top of the sidewalls to the front.
Those channels have four holes in them, with four stainless tubes that bridge across the top of the box. Those tubes are perforated, so the combustion air is preheated in the channels and shot out onto the baffle. This definitely makes the furnace a gasifier. When burning hot, and even moreso when the draft first closes, the hot air shooting out those tubes ignites the gasses and they look just like the burners in a gas furnace.
-The stainless baffle sits on those tubes. In normal operation, that baffle is shoved to the back and gasses move to the front of the baffle then to the back of the box above the baffle to exit. When you clean the heat exchanger (very convenient with a door on the front of the furnace), you first slide the baffle to the front so the soot from the side exchanger tubes drops back into the box. For the center tube you either pull the soot out the front of the furnace or shove it back into the stovepipe. Mine has a t behind it for easy cleanout.
- When the draft is open, the primary combustion air (cold) drops right down the inside face of the glass door (because it's cold) and then flows back across the coals and wood. The wood and coals in the box burn from front to back because the lower oxygen gets used up ... and then the gasses burn from back to front.So the total airflow sequence is ...
1) Front to back across coals and wood
2) Back to front across baffle and jets to burn gasses
3) Front to back across top of firebox to complete combustion before exit
4) Back to front through two heat exchanger tubes that are completely exposed in plenum
5) Front to back through center heat exchanger tube in plenum
6) Exit furnace through cold air return, slightly preheating the returning house air

My minor gripes about the furnace:
-Ashbox is useless and should be eliminated.
-Airflow into coals is less than effective. Should use a grate with slight airflow below, while keeping major airflow across coals as currently designed. This would also help with ash cleanout.
-Stainless baffle is heavy but it still warps a lot in the heat. Some of my gasses now escape around the edges ... not a serious loss.
-Stainless tubes are held in place by stainless pins that distort and break. Instead they should have a right-angle notch so you slide them in and then twist to secure ... with the twist in the opposite direction that you'd push them when sliding in firewood.
- Slight leaks when blower is running ... I can feel the air blowing out around the door frame.
- Leaks into the firebox when blower is running ... if it kicks in while loading the box, you might get a little ash and smoke blown out the door. But perhaps this is by design, so the blower boosts the flame a bit, dunno.

If I had more money I'd have done a water-to-air system, and in a new house I'd do water in floors with a forced air system for backup and A/C. Having a gasifier turn itself on and off is a waste of its design. Better to burn a full box of wood at top gasification temperature all the way, and capture that energy in a water tank heat sink to use as needed.

Hope your new setup is working well for you.
 
Wow, what a write up. Our home is 2400 sqft, a little drafty but well insulated. Our furnace keeps us warm and we use no fossil fuels. I wonder why you put a grate in the furnace? It's not necessary, and in the morning when I wake the front of the firebox is just ash that's shoveled out. Maybe poor draft? You can adjust the primary opening a hair, that's what we do. I've considered putting a firebrick in place of the ash grate, but I use it on occasion. If your baffle isn't seating, I would purchase their c-cast baffles. Much lighter, and won't warp. I'm thinking burning on the grate is pushing the limits of the furnace. It sounds like the Max-Caddy have been a better fit. I forgot to add, could you measure the openings to the secondary system, the 2 openings at the front of the furnace? I'm curious because you say theyre around an inch and ours are much bigger.
 
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I wonder why you put a grate in the furnace? ... I'm thinking burning on the grate is pushing the limits of the furnace .... It sounds like the Max-Caddy have been a better fit.
I really doesn't do much. Puts a little bit of air under the coals, a tiny % of the flow. Helps coals coals burn completely front to back. I used to get a pile of charcoal at the back that died, especially oak. Mostly the grate makes it easier to shovel out pure ashes that sift through and leave coals behind. I lever it up with a handy semicircle tool they provided for cleaning the heat exchanger. I doubt it affects the temperature at the top of the box. The fire burns about the same even when the space under the grate is full of ash. MaxCaddy might have been better for us, it does run a lot when cold, but the smaller furnace lets us use it more on moderate days.
You can adjust the primary opening a hair, that's what we do.I forgot to add, could you measure the openings to the secondary system, the 2 openings at the front of the furnace? I'm curious because you say they"re around an inch and ours are much bigger.
Your descriptions seem odd to me. Dunno how you can adjust anything. I'll post an annotated picture when I am not on my paranoid work network.

Dunno what you mean about the different baffle, will research it. I have some stainless here too, thought about working something up. Having it a little wavy doesn't hurt much.

Also I should have added to my gripes: Fiberglass insulation on back of heat exchanger door goes to bits, and on top of baffle seems to collect a bunch of stuff so the baffle gets really heavy.
 
Dunno what you mean about the different baffle, will research it. I have some stainless here too, thought about working something up. Having it a little wavy doesn't hurt much.
.
They changed from using the steel baffle to the c-cast one a few years ago and c-cast can withstand higher temperatures without warping/deterioration. It's also more brittle than the stainless one you have, though with some care loading splits it's not an issue.

I'll second the notion that the added grate is unnecessary, though at the same time I realize that it would help with clean out of the ash. While I think it could be done better, the ash grate isn't that bad. I just made a homemade tool to rack the coals/ash back and forth over the grate area - most of it falls down, but some left behind isn't a big deal. I'd rather empty the big ash tray than make many small scoops of ash when cleaning mine out.
 
On the arm of the damper, it's just thin metal. I tweak this a little to allow a little extra combustion air when closed.
 
I have approximately 2200 sq ft of living space along with a 800 sq ft basement. House is all 2x6 construction insulated fairly well. Last year was my first year and I burned around 2 full cords of hardwood. We generally only run the wood furnace when it is below 40. Keep the house around 71. I live central Ohio, so I am in zone 5.

Thoroughly impressed with the unit now I have it hooked up correctly. My only complaint is smoke comes in the house when I open the door sometimes. That could be a draft issue since I only have 18 feet of pipe.

If money was no object, I would get a lambda based boiler with storage. I broke the bank with my geo unit and the CFO put the brakes on spending more $$$ on HVÀC. The geo unit is well worth the money though.

Scott
 
My minor gripes about the furnace:
-Ashbox is useless and should be eliminated. Many user tell us they like it. The ashbox was also designed as a shovel that fits in the door to shovel out the ashes.

-Stainless baffle is heavy but it still warps a lot in the heat. We've now gone with thick C cast wich will not bend or degrade.

-Stainless tubes are held in place by stainless pins that distort and break. Instead they should have a right-angle notch so you slide them in and then twist to secure ... with the twist in the opposite direction that you'd push them when sliding in firewood. We're working on that...

See my comments above
 
hey guys, Ive been on the road for a while.

Well the move to the new house went well, although I still haven't sold the old house... argh.

I have a couple questions for you psg caddy owners.
What are your limits set at?
I cant get my fan to kick into medium so I switched the contacts so when the fan kicks on its on medium, and the plenum probe is set at 120/160.
If you fill your box can you maintain 66F for 10hrs?
Do you run a digital or mercury thermometer?

There is virtually no smoke coming from the chimney, which means its a good clean burn. The first couple of days the draft wasnt set quite right and I got a little brown on the glass ( evidence of a smoldering/ not hot enough fire)

now that the F#$*&#$ inlaws are gone....( there from MD) I can keep the house the way I want it and not at 70 ALL DAY F&(#@# LONG
66 @ 6:30-7:45 wake up and get ready for work
59 @7:45-4:45 gone to work
66@4:45-8:30 get home from work
58@8:30-6:45 sleepin time
 
Our is 100 off 145-150 on. It's currently 26, last night it dropped to 22. I loaded our furnace at 10:00pm, it was 74 in the house when I went to bed. I turned the thermostat down to 72. During the night, our thermometer said we peaked at 76 in the house and at 7:30 am it was 71. There was a nice coal bed, and I loaded 3 splits and turned the thermostat up to 73 where it's currently at.

I don't see what your referencing as medium? The higher the on temp, the longer it takes the furnace to put heat back into the home. With your off and on so close, it shouldn't be a problem though. The manual calls for 100 off 150 on. With those temps in your home, I'd freeze. The only time I keep the house in the low 70's is when it hits below zero and the heating demand is very high.
 
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