Used Woodmaster 4400 Questions

[Dragsterracer]

I need to educate myself for a possible purchase. I saw a used WM 4400 locally for sale. I have not called and asked questions yet, and that is part of what I want to find out here. What do I ask?
I have heated to some extent my house with our higher efficiency fireplace since we owned the house, but we cannot sustain a night-long fire, and it uses wood inefficiently. I have considered an outdoor boiler for some time. Our house is 3000 sq ft plus the basement. We did put regular pex in the floor of the basement and garage when we built the house....but not the oxygen barrier type.
Ideally, I would start with a heat exchanger, and work my way into perhaps using the floor heat pex and even getting some hot water as well.
What do I look for? What do I ask. Any pitfalls? It appears to be in excellent condition from the outside. I was not able to look inside the box as it was locked.
They are at $3500 obo, which seems high for any used outdoor boiler to me considering the possible expense of replacing parts that may not be in good shape at this point. But there is the "obo".
Also, what are the pro's and con's of this brand and model?
Thanks in advance for any help. I need it!

 

[Dragsterracer]

Don't be shy! I don't know much so even bad advice will be appreciated.....as I don't know any better.

 

[hobbyheater]

The biggest problem that I have experienced with wood boilers, although none outside boilers . The problem is trying to match the heating load to the continuous output of any wood boiler be it indoor or outside .
I believe as the technology of wood burning exists today , the best way to equalize the load to output problem is to use heat storage . Sizing a wood boiler to burn a full charge of wood at full output and have the fire burn out at the same time that the heat storage tank achieves full temperature or close to it .
I have operated a none gasification boiler connected to our 1,000 gallon storage it burned 10 cords per year .This same boiler burned 16 cords per year without storage!
Our gasification boiler ( 30 + year old Jetstream) connected to the same 1,000 gallon storage , with the same load only burns 4 1/2 cords per year .
I have never seen a Hardy but what I have drawn from this forum on the longevity of outside wood boilers , as rule their life span is not much more than 10 years .The nature of a fire in a firebox surrounded by water is that the fire cannot burn very hot and with this same cool water jacket becoming caked in creosote , the moisture between creosote and the steel being corrosive and in turn eating through the steel .

 

[Dragsterracer]

I have an idea bouncing in my head about storage....or buffering. We don't use our basement much, and we have no heat to it. It stays cool but not terribly uncomfortable. But we have pex in the floor of the basement. If we did minor heating to the basement with priority to the furnace heat exchanger, that would actually be adding btu's to the house slowly at a metered rate, and may reduce our load during peak usage loads....when we want it warmer in the house. It would even out the usage enough that idle times should be at a minimum. Now, if it can still keep producing until I get home after work.

 

[hobbyheater]

I forgot to welcome you to "Hearth" in my last post ,so welcome
On the OWB make sure that it is allowed by the local authorities in your area , in many places even phase II outdoor units are disallowed
Myself I believe that most boilers can benefit by adding storage.
The heat loss from storage in your basement may or may not contribute to a noticeable amount of heat loss into your basement it all depends on how well your storage is insulated . Our boiler with a well insulated storage are in a separate insulated below grade room in the basement . In the summer we can go as much as 20 days between firings when just drawing DHW ,at the end of the 20 days that room will be around 55 degrees .

 

[Dragsterracer]

No problems with regulations here. Plus, it's a big property away from prying eyes.
I found out that the unit is 8 years old. Very well maintained. I spoke with him about his maintenance and he was pretty particular about it. Box looks great. He is taking a shift job that won't allow him to tend to a wood deal.
I found out he won't take less than $4k for it. That number is a little uncomfortable to me with the risk involved in an 8 year old unit. I don't know...

 

[maple1]

Personally, I would not touch a used OWB of any kind - 8 years is really getting up there for some of them. And when they do go seriously wrong, there is no simple replacement of parts to fix them - they are scrap.

Exactly what 'maintenance' did he do? And what is he replacing it with?

 

[hobbyheater]

(broken link removed to http://www.newhorizonstore.com/Category/101-special-deal-overstock-items.aspx)

 

[Dragsterracer]

I agree with the concern over 8 years.
Yearly he would scrape or brush the creosote from the inside. Every spring he would flush the water and replace with fresh softened water with conditioner. It has an ash auger. He would completely remove the ash at the end of the season and always had the cap on when not running it.
He switched to a propane boiler for heat.
I am amazed looking at it that it is as old as it is. But I also recognize the risk involved with an 8 year old owb. So the price needs to reflect the risk. He is asking more than half of new cost. That doesn't properly reflect the risk in my opinion.

 

[maple1]

I have to admit - I have no experience with outdoor boilers.

But replacing with fresh water each year would also introduce a bunch of fresh oxygen. Maybe the conditioner has the covered, but if he didn't get it right there could have been internal corrosion slowly going on all those 8 years that won't be evident until it is too late.

A friend of mine had to replace his Wood Doctor after only 4 years, it turned into a pile of leaky scrap. Not all are equal, but I hate seeing things like that happen to people.

Definitely doesn't reflect the risk.

 

[700renegade]

non-barrier pex in your slab isn't an issue with a non-pressurized OWB. It will require a heat exchanger if you run a pressurized unit.

If you thought your high efficiency fireplace churned thru wood, wait till you get an OWB! I'm sure my fireplace insert can heat my house on less wood per year than my gasser. OWB is going to compare very poorly.