Max Caddy combo Electric installation

[David_QC]

I have my furnace installed, here are some pictures for your information. any advice are welcome.

I didn't run it at full load, but plenum temperature is below what I would think it would be...

For Electric:
25kW electric, after 30minutes of running time, it is stable at 115F... mode is Heat and Fan speed is 2.

Manual says that the BEP (best effiency point) Electric is 140F and Wood is 165F.

For Wood:
Almost half load of 2 x 4 I don't go over 140F when KIP (kick-in point) is 132F (maximum allowable) and it drop really fast till fan stop near 120F, then cycle on/off... the damper is full open all time.
Draft and Pressure looks good.

Maybe it need full load to go higher ? ... not cold enough for now...

Is anybody running it Electric with 20 or 25kW would tell me what is the plenum temp?


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[Highbeam]

Great install. Are those cables actually draped onto the chimney pipe in the first pic? I like the permanent manometer.

 

[David_QC]

Are those cables actually draped onto the chimney pipe in the first pic?

Thanks, there is no cable around chimney pipe other than the RTD temperature probe which is kind of metallic shielded cable. You can see the last picture, cables going up between return and plenum, they are for the electric and wood thermostats upstair. The manometer tubing is ty-wrapped with these cable and going inside plenum.. maybe this is the "cable" that look like draped with the chimney pipe in the first pic.

 

[DoubleB]

I'm not as familiar with the Max Caddy control system and temps, but a couple thoughts...

It might take a couple fires for the moisture to bake out of the firebrick. Until then, you might get low temperatures and/or they might drop off fast.

Also, make sure your baffle is towards the rear of the furnace.

Others might correct me on that, though.

 

[STIHLY DAN]

Nice unit.. A couple of things though, not a good idea to have the flex connector on the supply there. The tape on the joints (may) give off an odor and that is kind of a long horizontal run on the flue. That could create draft issues. Nice looking unit and install otherwise.

 

[laynes69]

With the damper full open, it will send more heat out the flue. It will still produce heat, but not as much. Once loaded on a good coalbed, it should cruise with minimal air and produce a good bit of heat. You more than likely won't see output temps of a gas furnace, but you don't want too either. Your furnace will produce a lower heat, but run longer than a conventional furnace. I worried about ours for the first year and found that 100-105 degrees will more than heat the home when cold. You'll find when it gets cold and you push the furnace, it should more than exceed your expectations.

 

[brenndatomu]

Howdy David! Lookin good.
So did you get that chimney lined liked you talked about back in the spring?
What are your draft and static pressure #s like?
I wouldn't think it is cold enough yet to have great draft, especially after the intake damper is closed for awhile.

 

[David_QC]

So did you get that chimney lined liked you talked about back in the spring?

Yes it is lined ! I went with the not insulated finally... Draft is much better, it was originally too high; from 0.13 to 0.06 with draft controller fully close to fully open. Now it is 0.08 to i guess 0.00... It was easy to adjust to 0.06 and it just crack open a bit once in a while.... but as you said, draft will increase when it will get colder, we will see...

Static pressure is 0.25 at the second speed (you can see it at the first picture)
Draft is 0.06

I will update this as soon as i can load it again and make more tests...
Yesterday I filled a lot of hole in the return duct, they are made of metal plate between joist and there is lot of hole for electric cable... I spent two can of stuff to fill every hole...

 

[brenndatomu]

Yes it is lined ! I went with the not insulated finally... Draft is much better, it was originally too high; from 0.13 to 0.06 with draft controller fully close to fully open. Now it is 0.08 to i guess 0.00..

I'm confused...the draft went down with a liner? It should have went up...way up.
Do you switch the tubes (between "hi" and "lo") on the Dwyer when you go between checking pressure and vacuum (draft)? I do, it keeps the fluid to the right of the zero, a lot easier to read and much more range

 

[David_QC]

Yes draft went down with the liner, chimney diameter was a bit less than 8 inch without cap and now it is 5.5 inch with a cap. Chimney lenght is somewhere between 35 and 40 ft...
I don't know the mathematics about draft and diameter, but I'm happy it went down, because draft controller was eating lot of fresh air...
I don't know how much cold temperature outside will change draft, hope it's not too much...
Yes I switch Hi and Lo, you can see 1st picture one tube is going into plenum, Last picture you can see the tube is hanging near the chimney pipe. I remove the plenum tube when I measure the chimney pipe.

 

[sloeffle]

Is the damper on the Max Caddy controlled by a computer ?

 

[David_QC]

Is the damper on the Max Caddy controlled by a computer ?

It is the thermostat that control the damper, there is no advanced control with damper. Damper motor is a On/Off (full open or full close) actuator. The controller you see with temperature reading is basically for fan speed based on plenum temperature. Looks nice, but it give less adjustments on start temp. setpoint and the stop temp. setpoint than normal furnace like the Caddy version. For example, I would set my Start at 150F and Stop at 110F, but with the fancy controller I can't do that, I can only change the Start point and it stop 20 degree below the start, which make it start/stop cycling... that span is not configurable...

 

[lexybird]

I'd call sbi, I have a max caddy too btw

 

[sloeffle]

It is the thermostat that control the damper, there is no advanced control with damper. Damper motor is a On/Off (full open or full close) actuator. The controller you see with temperature reading is basically for fan speed based on plenum temperature. Looks nice, but it give less adjustments on start temp. setpoint and the stop temp. setpoint than normal furnace like the Caddy version. For example, I would set my Start at 150F and Stop at 110F, but with the fancy controller I can't do that, I can only change the Start point and it stop 20 degree below the start, which make it start/stop cycling... that span is not configurable...

It make you wonder why PSG hasn't come out with a furnace that is fully run by a computer / PLC. They could have the computer run the damper and a DC motor for the blower. Maybe the price point would be too high.

 

[lexybird]

I think the seperate damper control makes the most sense over a Plc setup . The furnace may know a set parameter of temperature to activate the damper but it can never really know if your house is comfortable in the real world ,the only way I'd say that could be close is by it being activated by a seperate digital thermostat upstairs in the living area away from the unit , plus you start adding extra complication to the furnace and it's more of a chance for problems and cost

 

[lexybird]

I relocated my rti probe on the side and moved it up so it's only about an inch from the front of the plenum .this is hottest spot in the plenum . By doing this it thinks it's hotter than it really is basically It tricks the PC board and keeps the blower on longer and more efficient on wood use . This mod is a huge help ,if the fan cools it down below your setting the blower shuts down - then it won't heat the upstairs and as a result the thermostat calls for more heat thus keeping your air damper open which just compounds your problem a great deal by sending heat up flu and eating up firewood ! you may want to experiment with probe placement so it's not in direct path of the rushing air , speaking of which - this blower could launch a Boeing 747 into the air man is that sucker strong at high setting

 

[gonefishin]

I am very impressed by the Max Caddy. I have been looking for either a woodburning stove (hearthstone) or for a very long time. I had an authorized dealer come out yesterday to give me a quote I was shocked. My furnace has some electronic dampers for zones one and two. So we are working with the heating company that installed the honeywell hardware to see if the max caddy will work. However the quote came back at $12,000 without hooking the max caddy to the furnace. so, looking at another grand easily to hook it up to furnace. Is this normal for installation? the price did include a blower and a chimney installed. This just seems very expensive. Just looking for feedback.

 

[gonefishin]

One more thing, the black pipe leading from the max caddy leaves your house and connects to your chimney correct? This means that when your pipe leaves the house it turns 90 degrees straight up? Do you notice any decrease in drafts due to this?

 

[brenndatomu]

This just seems very expensive. Just looking for feedback.

Seems a lil high, but it depends what all is included and what kind of obstacles they have to deal with to do this install. Some houses lend themselves to a wood furnace install better than others. How about a breakdown of the quote?
Sounds like your chimney setup would be pretty standard. As long as everything is correct, there should not be draft issues
Where you at in NEO?

 

[DoubleB]

quote came back at $12,000

Last spring I got a quote for $10,000 to install a Max. $6000 for the furnace (with oil burner) and the rest for ductwork, chimney, etc. All seemed too high. I went with a different option.

 

[brenndatomu]

If you are wanting to burn wood to save money, that kind of an install price sure draws out the payback period, especially at current fossil fuel prices. If you are doing it for other reasons than I guess all you have to do is justify it to yourself

 

[Wisneaky]

If you are wanting to burn wood to save money, that kind of an install price sure draws out the payback period, especially at current fossil fuel prices. If you are doing it for other reasons than I guess all you have to do is justify it to yourself

In reality though why spend that kind of money when you could buy a Kuuma for half that price?

 

[David_QC]

I relocated my rti probe on the side and moved it up so it's only about an inch from the front of the plenum .this is hottest spot in the plenum . By doing this it thinks it's hotter than it really is basically It tricks the PC board and keeps the blower on longer and more efficient on wood use .

I'm experimenting that presently, I did 2 holes at 1 inch of distance ( 1 inch is based on another post from someone who did that for his Caddy), for me 2 inch = no results, but i'm still far from the front, I will try like you did tonight, I can feel by touch of the plenum that the front is MUCH hotter than the middle/back. I have to set the controller manually at speed 1 to prevent cycling of the fan. I will post if it's working better... I hope it will work, because speed 1 with 25kw of electric heating is making the bottom side of the furnace really hot... See IR picture... (111C = 232F) not sure if temp result is accurate, there was lot of parameter in this IR device that was making a big difference of the temp reading (metal reflection)...

 

[David_QC]

However the quote came back at $12,000 without hooking the max caddy to the furnace.

In Quebec, Canada :
Max Caddy Wood only : 2800$ (include fan, +15%tax), I moved it to the basement myself.
Hooking to the chimney : don't remember, maybe 250$ with a draft controller ?
40Ft 6inch liner not insulated: 1300$ +tx installed by a sweeper
25kW element : 700$ (our electric rate is 8,6 cent per kw/h)
Connecting the 25kW to the electric panel : 500$ material + 160$ electrician. (breaker and cable cost a lot more than I tought...)
Duct work : I already had duct installed for my old oil furnace, it cost somewhere around 1800$ with a full box of 4 inch filter to fit the caddy to the existing duct, was done by a cheapo duct contractor.

 

[David_QC]

One more thing, the black pipe leading from the max caddy leaves your house and connects to your chimney correct? This means that when your pipe leaves the house it turns 90 degrees straight up? Do you notice any decrease in drafts due to this?

I had too much draft with my unlined 8 inch 40FT chimney, now I'm just right with the actual setup. Draft controller open rarely or just a bit and i'm right on the spec draft... Maybe I will even remove the draft controller and save on some horizontal distance by ajusting these 2 x 45 bent... I found out some thick creosote glue on the draft controller door, it's sucking a bit of cold air.. don't enjoying it... but I will wait and see before changing anything.