Vermont Castings Merrimack

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Well, it's 33 degrees outside, and my whole house is pretty toasty! I'm very happy with the Merrimack. It's rather easy to get a fire going, and the warmth can't be better. My dog and cat have taken up residence in front of it, and the cat gets rather annoyed when I move him to put more wood in. Little creep!
I am a happy girl, and my oil heat is still switched to "off". Woo Hoo!

Now, if I could find a gas station that has gas and a line less than 2 miles long...
 
We are already into oil for $1,600 since August and it hasn't even gotten cold yet. So....

We had a Merrimack installed a few weeks ago. We always had a fire going in our open fireplace and wanted to get some heat out of it.... while still having a good view/ambiance of the fire itself.
It's going to take some years to recoup the costs of the stove/install, but we burned wood anyway, so why not get some heat out of it.
Using just oil we'd never have the downstairs as toasty as it is with the Merrimack either.

So far we are very happy with the unit. The view of the fire is superb and the heat output is awesome.
We liked the flush inserts, but the view and firebox size on the Merrimack had us lean towards it.
We run the fans about halfway and hardly notice the noise. At full speed they are louder, but not annoying as others have reported. Perhaps in time they will get loud. For now they are fine. No issue.

After the first 4 break-in fires I've been burning her full bore 24/7 since.
The house is 4200 sq/ft so it doesn't heat the whole place, but it sure keeps the boiler from firing like it was.
Like I said earlier, it's also much warmer downstairs than we would keep it using just oil.
Keeping it this warm with just oil would be kid college fund damage.

It's been simple to operate. The glass stays extremely clean and burns clean. Excellent wood source takes credit here.

One thing I really miss from the open fireplace days is dealing with the ash. The 'ol endless ash pan trap door is now buried in it's glory under this behemoth of cast iron.
Having to scoop out ash into the ash bucket is a drag.

I'm getting some good burns out of it. Load her up at 11PM and wake up to a bed of coals waiting to be fed.
I haven't touched a match in weeks. Although, I sure have put a dent in the wood stack.
I'm feeding her close to a 1/4 cord per week and I damp her all the way down.
Wish I could choke her a bit more, but I think the EPA had their hands in that one.

 
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We are already into oil for $1,600 since August and it hasn't even gotten cold yet. So....

We had a Merrimack installed a few weeks ago. We always had a fire going in our open fireplace and wanted to get some heat out of it.... while still having a good view/ambiance of the fire itself.
It's going to take some years to recoup the costs of the stove/install, but we burned wood anyway, so why not get some heat out of it.
Using just oil we'd never have the downstairs as toasty as it is with the Merrimack either.

So far we are very happy with the unit. The view of the fire is superb and the heat output is awesome.
We liked the flush inserts, but the view and firebox size on the Merrimack had us lean towards it.
We run the fans about halfway and hardly notice the noise. At full speed they are louder, but not annoying as others have reported. Perhaps in time they will get loud. For now they are fine. No issue.

After the first 4 break-in fires I've been burning her full bore 24/7 since.
The house is 4200 sq/ft so it doesn't heat the whole place, but it sure keeps the boiler from firing like it was.
Like I said earlier, it's also much warmer downstairs than we would keep it using just oil.
Keeping it this warm with just oil would be kid college fund damage.

It's been simple to operate. The glass stays extremely clean and burns clean. Excellent wood source takes credit here.

One thing I really miss from the open fireplace days is dealing with the ash. The 'ol endless ash pan trap door is now buried in it's glory under this behemoth of cast iron.
Having to scoop out ash into the ash bucket is a drag.

I'm getting some good burns out of it. Load her up at 11PM and wake up to a bed of coals waiting to be fed.
I haven't touched a match in weeks. Although, I sure have put a dent in the wood stack.
I'm feeding her close to a 1/4 cord per week and I damp her all the way down.
Wish I could choke her a bit more, but I think the EPA had their hands in that one.



Do you mean a 1/4 face cord a week? If so that's not too bad. What a beautiful insert you have.
 
A cord a month isn't bad for a nice warm house. Look at the amount of oil you were burning and it put's in in perspective.

PLUS, it's pretty!
 
I've had my VCM since last March, I got it just at the tail end of the heating season here in Michigan. So far this year hasn't been much of a challenge, 15 degrees at night and 35 in the day time, nothing really cold to challenge the insert. Our furnace is set at 70, but most of the time the house is staying at 72-75 when I keep the fire going. As long as the temp doesn't drop below 70, the natural gas burning furnace stays off!! I'm hoping the in the peek months of Jan & February I can cut our heating bill from 350$/month to under 100$ (we have a gas hot water heater) On a yearly average, I was hoping for a 1000$ a year savings, and in four - five years the whole installation would be paid for. Does anyone else think they are approaching this level of savings?

A few issue I have had that I am wondering how others are handling:

Ash cleanup: It's takes a long time for the ash to cool down enough to empty. I normally have a fire for about 3-4 days straight (the ash gets so high that the heat output drops drastically, then I have to go for almost 2 days without a fire while waiting for it to cool enough to empty. How are VCM owners handing this. Is there a more practical method for emptying hot ashes? There isn't a vacuum that can handle this sort of thing is there?

Fan motors clogging: The grids on the fan motors where the air is sucked through the base seems to get clogged after a few months. I notice the amount of air flow drops significantly. I've had to start checking them on a monthly basis and cleaning them out...is anyone else having this issue. I solved the burns issue with a "Past the elbow" pair of fireplace gloves. I think I'm going through about 1/3 of a face cord of wood/week. More then I would like, I'm burning a combination of oak and ash and the burns normally are lasting about 6-7 hours.

Glass cleaning: The glass does seem to get clouded with smoke after a few days of burning to the point where I can't see the fire at all. I've solved the problem with the yellow cans of oven cleaner. It's the only thing I have found the cleans the inside of the glass. Nothing else will cut it. How come I'm not hearing others having this issue...am I doing something wrong that could be causing this issue?
 
Install went great yesterday- very pleased with the aesthetics of the stove. However, during the install the cast piece on the door latch (small part the roller screws into) cracked! The installer said this was somewhat common, which I can imagine. Replacement part will be here this week until then I can't use the stove. Anyone else have the part break? Being a small cast piece, I was thinking of getting one machined out of solid steel so I would not need to worry about it.

View attachment 78449
That is a real bummer. I will be more careful about opening and closing the doors, I'd never thought that part might be fragile...maybe there was a flaw in the cast iron.
 
I have had the stove for 2 solid months now, burned about 2 full cord (about 1/4 cord per week - full loads except for when we are at work, where we just put a log or two on to keep the temp up). Overall I am in love with the stove. It sure will offset our propane bill in the 4000+ sq ft open floorplan house. Here is my opinion on a few of the issues posted by other owners, plus some of my own....

Ash cleanout: I have a homemade ash "sifter" that separates the large embers from the fine ash, then I use a fire resistant ash vacuum to take care of the rest to keep the ash at an acceptable depth, without full cool-downs to clean out. Plus the ash vac does a great job keeping the hearth tidy.

Glass cleaning: I clean the glass about once a week. When the stove is relatively cool (you can touch the glass without getting burned) I spray simple windex on the inside, let it sit for a few seconds, and use a razor blade to scrape the inside of the glass while it is wet. The dirtyer the glass the easier it is to clean. After a "scrape job" I repeat the windex spray, wipe with paper towels clean and done.

Fan Motor clogging: Not a problem (yet).

Fan Motor noise: Got used to it. Not annoying enough to do anything about, sounds like saving money to me.

Thermostatic Fan motor switch seems possessed: I have not yet understood what it takes to get the switch to work consistently. If I put my canvas log carrier in front of the air intake, it stops the natural convection through the stove, and seems to get the fans to click on faster. I am seriously considering bypassing the thermal switch so only the dial knob is in control, any thoughts? Sometimes it takes 1-2hrs for the switch to activate, even though the stove is completely up to temp.

Automatic air flow: I am talking about when you push the lever to the left to set the trip feature. Supposedly, when you refill the stove, especially in the morning when it the firebox has coals but is cooled down, you should push the lever all the way to the left to open the airflow, load the stove, then move it to the desired burn setting (for me all the way to the right), and the airflow will stay open until the stove comes up to temp. I have never seemed to get this to work. The airflow seems to not stay open as I set the burn setting low, all the way to the right.

Fan Motor Speed: The manual says to not put the fan on "high" when you have the burn setting on "low" - lever all the way to the right. I put one of the magnetic stack temp gauges (rutland made mine) to the front of the stove where the air exits. I am getting 300F air exit temp mid-burn for several hours on a full load with the lever to the right and fan on high. Putting the fan on low has no affect on the air exit temp. If there was a difference in the exit air temp, then I could see the fan speed having an effect. More of the same 300F temp air is more heat output from the stove and into my house, so I am running the fan on high. It is also interesting to note that I am not getting much difference in exit air temp if I put the lever midpoint or full open... Maybe 325F with the blower on high. Not much more heat, but the burn time is greatly reduced. Of course this all could be a function of the wood quality I have, which I bought this first year (and was told was "seasoned" - which I believe is true as it doesn't hiss or steam when burning). I also ran the fan on low with the burn setting on "low" a few times and it has no effect on burn time vs. having the fan on high. So the only reason I think I would ever put the fan speed on low is if it got too hot in the room (not a problem with my open floorplan) or if I wanted a quieter environment...
 
I have had the stove for 2 solid months now, burned about 2 full cord (about 1/4 cord per week - full loads except for when we are at work, where we just put a log or two on to keep the temp up). Overall I am in love with the stove. It sure will offset our propane bill in the 4000+ sq ft open floorplan house. Here is my opinion on a few of the issues posted by other owners, plus some of my own....

Ash cleanout: I have a homemade ash "sifter" that separates the large embers from the fine ash, then I use a fire resistant ash vacuum to take care of the rest to keep the ash at an acceptable depth, without full cool-downs to clean out. Plus the ash vac does a great job keeping the hearth tidy.

Glass cleaning: I clean the glass about once a week. When the stove is relatively cool (you can touch the glass without getting burned) I spray simple windex on the inside, let it sit for a few seconds, and use a razor blade to scrape the inside of the glass while it is wet. The dirtyer the glass the easier it is to clean. After a "scrape job" I repeat the windex spray, wipe with paper towels clean and done.

Fan Motor clogging: Not a problem (yet).

Fan Motor noise: Got used to it. Not annoying enough to do anything about, sounds like saving money to me.

Thermostatic Fan motor switch seems possessed: I have not yet understood what it takes to get the switch to work consistently. If I put my canvas log carrier in front of the air intake, it stops the natural convection through the stove, and seems to get the fans to click on faster. I am seriously considering bypassing the thermal switch so only the dial knob is in control, any thoughts? Sometimes it takes 1-2hrs for the switch to activate, even though the stove is completely up to temp.

Automatic air flow: I am talking about when you push the lever to the left to set the trip feature. Supposedly, when you refill the stove, especially in the morning when it the firebox has coals but is cooled down, you should push the lever all the way to the left to open the airflow, load the stove, then move it to the desired burn setting (for me all the way to the right), and the airflow will stay open until the stove comes up to temp. I have never seemed to get this to work. The airflow seems to not stay open as I set the burn setting low, all the way to the right.

Fan Motor Speed: The manual says to not put the fan on "high" when you have the burn setting on "low" - lever all the way to the right. I put one of the magnetic stack temp gauges (rutland made mine) to the front of the stove where the air exits. I am getting 300F air exit temp mid-burn for several hours on a full load with the lever to the right and fan on high. Putting the fan on low has no affect on the air exit temp. If there was a difference in the exit air temp, then I could see the fan speed having an effect. More of the same 300F temp air is more heat output from the stove and into my house, so I am running the fan on high. It is also interesting to note that I am not getting much difference in exit air temp if I put the lever midpoint or full open... Maybe 325F with the blower on high. Not much more heat, but the burn time is greatly reduced. Of course this all could be a function of the wood quality I have, which I bought this first year (and was told was "seasoned" - which I believe is true as it doesn't hiss or steam when burning). I also ran the fan on low with the burn setting on "low" a few times and it has no effect on burn time vs. having the fan on high. So the only reason I think I would ever put the fan speed on low is if it got too hot in the room (not a problem with my open floorplan) or if I wanted a quieter environment...


I'm on season 3, burning 6-8 cord per year on the merrimack. It has replaced my two propane furnances as the primary heat source for my 3000+ sqft house, so barring the fan noise I really like this unit. I have ripped this thing appart a couple of times, and on the automatic air flow it's a pretty basic setup, so something might be wrong if it isn't staying engaged. The top front of the stove lifts off pretty easily, so viewing the mechanism isn't too tough. When I first got mine the lever didn't seem to work either, and I found that the little cable that pulls the flap up wasn't connected. I also recently found that the little auto air box wasn't seated uniformly to the top of the stove, so even when fully closed some air was sneaking by. A couple of screws and a little bendable tab hold it in place, so 5 minutes later I had a slower burning fire.

I also run mine almost exclusively in the fully closed and full fan position, and last year only had creosote buildup on the chimney cap, essentially nothing in the steel liner. I don't think these blowers age well since I'm on my third, and after time all of them have become quieter in the high setting than anything lower. They are really cheaply designed, so I think things are wearing internally that causes the fans to wobble at low levels and make the surrounding metal vibrate.
 
I'm on season 3, burning 6-8 cord per year on the merrimack. It has replaced my two propane furnances as the primary heat source for my 3000+ sqft house, so barring the fan noise I really like this unit. I have ripped this thing appart a couple of times, and on the automatic air flow it's a pretty basic setup, so something might be wrong if it isn't staying engaged. The top front of the stove lifts off pretty easily, so viewing the mechanism isn't too tough. When I first got mine the lever didn't seem to work either, and I found that the little cable that pulls the flap up wasn't connected. I also recently found that the little auto air box wasn't seated uniformly to the top of the stove, so even when fully closed some air was sneaking by. A couple of screws and a little bendable tab hold it in place, so 5 minutes later I had a slower burning fire.

I also run mine almost exclusively in the fully closed and full fan position, and last year only had creosote buildup on the chimney cap, essentially nothing in the steel liner. I don't think these blowers age well since I'm on my third, and after time all of them have become quieter in the high setting than anything lower. They are really cheaply designed, so I think things are wearing internally that causes the fans to wobble at low levels and make the surrounding metal vibrate.

Now I am curious, I've lifted up that lid on top and looked at that little box and the cable is connected to it. The little flange on top seems to want to lay down all the time. Is that the low air position or the open air position. How is it supposed to behave. When the stove heats up is it supposed to stand up and cut down the air flow?

Has any one tried using the Ash Dragon on the Merrimack? I've been struggling with getting to much ash, and shutting the system down completely, letting it cool then emptying the ash. They claim with this Ash Dragon and mated screen device you can separate the ash from the hot coals and then scoop out the ash leaving the hot coals behind, allowing 24hr operation. I'm thinking seriously of paying the C note to try it. It's also supposed to reduce the amount of ash that gets free in the house....my wife would love it if it did.
 
Now I am curious, I've lifted up that lid on top and looked at that little box and the cable is connected to it. The little flange on top seems to want to lay down all the time. Is that the low air position or the open air position. How is it supposed to behave. When the stove heats up is it supposed to stand up and cut down the air flow?

Has any one tried using the Ash Dragon on the Merrimack? I've been struggling with getting to much ash, and shutting the system down completely, letting it cool then emptying the ash. They claim with this Ash Dragon and mated screen device you can separate the ash from the hot coals and then scoop out the ash leaving the hot coals behind, allowing 24hr operation. I'm thinking seriously of paying the C note to try it. It's also supposed to reduce the amount of ash that gets free in the house....my wife would love it if it did.

Mine only moves toward the flat position as the cable is lifting the air flap. Once the flap is up, the flange you are referring too goes back to its resting position since its now engaged. Only comparison I can think of now is like the part of a mousetrap where you stick the bait. Once the spring inside the box gets to temp, it moves the flange a little bit, releasing the catch on the air flap. Makes a very noticeable clicking noise as the draft quickly sucks it down and metal hits metal.

You'd know if its stuck open since it makes a noticeable sucking sound, and the fire will rage regardless of lever position. The hole is about an inch big, an a direct feed to the firebox, so a much less restrictive path than the normal primary air path.
 
Couple of things....

Put a watt meter on the fan outlet. The fans draw 150-155 Watts at full speed.

Here's some pictures of the primary air top, bottom and autosetback air.

View from top after removing auto-setback control:
MerrimackAutomaticSetback.png


View of lower air intake after removing refractory brick. These inlets are not adjustable:
MerrimackLowerPrimary.png


Primary air top inlets with glass wash deflector removed:
MerrimackPrimaryAirClosed.png

View of top Primary air inlets in open position:
MerrimackPrimaryAirOpen.png
 
Great pictures, thank you. There is a lot of information with them. I just had a Merrimack installed last night. I'm almost done with the preliminary burns and will posts pictures when I'm doing full burns.
 
Now I am curious, I've lifted up that lid on top and looked at that little box and the cable is connected to it. The little flange on top seems to want to lay down all the time. Is that the low air position or the open air position. How is it supposed to behave. When the stove heats up is it supposed to stand up and cut down the air flow?

Has any one tried using the Ash Dragon on the Merrimack? I've been struggling with getting to much ash, and shutting the system down completely, letting it cool then emptying the ash. They claim with this Ash Dragon and mated screen device you can separate the ash from the hot coals and then scoop out the ash leaving the hot coals behind, allowing 24hr operation. I'm thinking seriously of paying the C note to try it. It's also supposed to reduce the amount of ash that gets free in the house....my wife would love it if it did.

I just push the coals to one side and scoop the ash out with a shovel into an ash can, then do the same for the opposite side, I do this when its time to reload, no need to let the stove get cold to clean ashes, wear gloves and be careful with the ash pan, its get hot.
 
Didn't think this was worth a whole new thread, but probably worth mentioning in the this VC merrimack repository or information. After three years and multiple blowers almost always making anoying noise something happened over the last week or so that has me wondering. The fan noise has stopped. The only difference has been that for the first time we have started running a whole house humidifier, and the space where the stove resides now hovers in the 30% range, where before the gauge was bottomed out. I'm not familiar with what in the blower if anything would be impacted by the humidity level, but this thing has suddenly gone from a rattling mess to a smooth sounding fan.

Probably just a fortunate coincidence, but I can honestly think of no other changes I've made, nor have I done any blower cleaning in the time between noisy to pleasant.
 
Thanks you everyone. My automatic setback air control box was not fully seated down against the top of the stove. I had about a 1/8-1/4 gap and you could hear the "whistle" even with the setback device flapper closed. I would say this is a very important "feature" for every stove owner to inspect - I am looking forward to the difference in burntime and blower exit air temp with the air leak now corrected.
Dan
 
Hi Dan,
How did you check to see if the gap in the automatic setback air control was seated properly? It sounds like a good thing to check.
Thanks for the heads up, Mike
 
I found it, it was easy to see when the door was open! It is seated properly but did not stay open when I checked it when the stove was cool and I pulled the automatic setback control to the left. I'm pretty sure it should stay open when cool, until the stove is up to operating temperature, right?
 
I found it, it was easy to see when the door was open! It is seated properly but did not stay open when I checked it when the stove was cool and I pulled the automatic setback control to the left. I'm pretty sure it should stay open when cool, until the stove is up to operating temperature, right?

I thought the idea was to keep the lever to the left until you have established a strongly burning fire, one that will sustain itself on much less air flow, then set the lever to the right and get the longest slowest burn possible to get the absolute maximum BTU's out of the wood and least amount wasted by going up the chimney...I could be wrong, if so, someone please correct me.
 
I just push the coals to one side and scoop the ash out with a shovel into an ash can, then do the same for the opposite side, I do this when its time to reload, no need to let the stove get cold to clean ashes, wear gloves and be careful with the ash pan, its get hot.

Thanks, I found a tool that really makes the easy and consequently severely reduces the amount of soot I put into the air. The Ash Dragon is a simple box with a handle and a lid that can enclose the soot once separated from the coals and transfer it outdoors without leaving any indoors on the furniture or in the air. So far it's working very well. It also provides a tool that is useful for separating the soot from the coals. No more kindling needed, the fire is now running continuously. Thanks for the advice, I'm following it exactly and using the Ash Dragon to capture and remove the soot and smaller coals. Works great. I also bought a metal trash 30 gallon trash can (on a patio stone) to store the hot soot and coals in while they cool down.
 
I thought the idea was to keep the lever to the left until you have established a strongly burning fire, one that will sustain itself on much less air flow, then set the lever to the right and get the longest slowest burn possible to get the absolute maximum BTU's out of the wood and least amount wasted by going up the chimney...I could be wrong, if so, someone please correct me.
Your right on the primary air control (it is to be set towards the right, most set it about and inch from full right) but to turn on the automatic setback control it is a push all the way to the left then you can set the primary air to the right, this is what the stove will go to when the stove gets up to operating temperature. Talking to my dealer we figured out what the problem is, the automatic setback flap is hitting the bottom of the catch and needs to be adjusted. It is the first time they have seen this problem with the automatic setback on this type of stove. They really went above and beyond to get this information from VC.
Thanks for the feedback; I should have been more clear on what I was trying to convey.
Mike