# Installed this boiler last week



## heaterman (Oct 6, 2012)

This is the WP pellet boiler that Marc Caluwe is manufacturing here in the States. The model you are looking at is the 135 with the XL pellet hopper which holds about 350# of pellets. It's a nice basic unit sold without a lot of bells and whistles.

We have it set up to simply run on the boiler temp setpoint (fully adjustable) and circulate heat to the 6,000 sq ft pole barn/machinery shop it is heating. The system inside is set up very nicely for this being 5 zones of radiant slab controlled Wirsbo room temp sensors and a Tekmar 356 injection mixing control. If I had my choice I would have liked to install it with an enable/disable control based on indoor temp but there is no option to run a control wire in the existing undergound conduit/piping. (Always run extra conduits in your underground people)

The boiler itself sits on a slab that used to have an OWB on it and the owner elected to build a little boiler shed to house it and have room for a pallet of pellets. The control on the boiler allows you to set your firing rate in 5 increments of roughly 20% so you can run this particular model at 20,40,60,80 or 100% of 135,000btu. It has a built in boiler protection aquastat that kills circulation if the water temp drops too low. I really like this feature because it makes piping and installation much less difficult than having to install a mixing device like a Termovar or equivalent.We have it set to start the boiler circ at about 145 and turn it off if the water temp hits 135*. This gives plenty of leeway to avoid condensation issues from excessively low water temps. (The Testo showed a dew point of 115-118* in the flue gas)

We have no storage connected to the boiler and I doubt very much if any will be needed in this particular case for a couple reasons. The first being that the boiler is capable of 5 different firing rates so its output can be matched to the outside conditions. The second being the nature of the system and load it is connected to. (variable demand due to proportional control of the load). This will allow the owner to basically set the boiler at level 2 (40%) until probably mid to late December and then step it up to 60% and maybe 80% during the January-February time frame.

The water temp setpoint is on at about 163 and off at 177 the way we have it set right now which gives us plenty of "headroom" before reaching emergency dump temperature setting of 210*. I purposely ran the boiler to about 170 at max firing rate and then killed the power to see what would happen. The water temp crept up to about 195 before stabilizing and then heading back down. This is a notable difference when compared to a cordwood fired boiler which can continue to make heat long after things are shut off due to a circ failure or power outage. There is only about a pound of fuel maximum in the firepot at one time so there is little residual heat rise. Makes it a lot less problematic from a dump zone standpoint.


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## kopeck (Oct 6, 2012)

Looks good to me.

I know there's tons of variables but how often do you think he will have to fill the hopper in the dead of winter?

K


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## heaterman (Oct 6, 2012)

Well let's see..........

Building load at design temps with all areas heated came out to a couple tenths above 17btu's per square foot. So 6,000 x 17 = 102,000 btu's at a 24 hour avg temp of -6*F for this area.
There are approximately 330,000 btu's in a 40 pound bag so one bag would run him for a little over 3 hours or almost 8 bags per day during peak load. (5% of the winter)

At a more normal 24 hour average temp of 18* the load drops to about 65,000 btu's per hour, again with the entire structure heated to the same temp. That would equal a little less than 5 bgs per day.

Given that he keeps about 2000 sq ft of the shop at 45* I'm guessing he'll see a winter average of a little less than 3 bags (120#'s of pellets) per day usage. Not bad for 6,000 sq ft with a 16' ceiling in half of it.


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## BoilerMan (Oct 7, 2012)

I like the ball valve on the expansion tank for fast changing/ pressure setting.  Always pumping away!  Looks great!

TS


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## Eric Johnson (Oct 7, 2012)

Taylor Sutherland said:


> I like the ball valve on the expansion tank for fast changing/ pressure setting.


 
That's the kind of thing you (read: me) learn the hard way.


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## BoilerMan (Oct 7, 2012)

Same goes with automatic air purgers.

TS


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## heaterman (Oct 7, 2012)

I'll get some pictures of the indoor piping when I get up there again later this week. It's an excellent illustration of P/S piping and if he ever decides to go with LP the gas boiler will install just like the pellet boiler did.


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## kopeck (Oct 7, 2012)

Seen these Taylor?

http://www.pexsupply.com/Webstone-4...Brass-Ball-Valve-w-Hi-Flow-Hose-Drain-600-WOG

Pretty slick...

K


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## Karl_northwind (Oct 8, 2012)

Looks nice. I have the literature and talked to marc extensively about them, and have been looking for applications. Could you use an ODR controller like a tekmar 256 to adjust the high temp automatically? A buffer tank would be necessary for most applications, but this one is really slick. Gotta love having high mass emitters.

am I missing something?  why are there 2 PRV's?

karl


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## DaveBP (Oct 8, 2012)

There is a certain beauty in simple design and a clean layout. At least to a certain type of person. I am one of those types.

I wonder though if it wouldn't look even more beautiful to the home owner's insurance agent with $10 worth of fire-rated drywall behind it in the corner. But I don't think it would add anything to the safety of the setup.


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## Gasifier (Oct 8, 2012)

Nice Heaterman. Nice. Thanks for sharing the pics.


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## Morgan (Oct 8, 2012)

Nice install, the only thing I would like to point out is pipe with 1" pipe you are limiting yourself to about 90K BTU heat transfer, 1.25" would have allowed about 160K BTU, on the coldest days of the year you could be looking at 45K BTU's that are not being able to be delivered to the slab without over pumping the 1" pipe which would lead to system noise.  Also why two relief valves?  And your blue dope, is that rectorseal?  Just started using it myself, I was a big leaklock fan but it has been letting be down lately.....mostly with coldstart systems, been getting drips, especially on my copper/brass threaded connections, rectorseal's non-hardening claims made me give it a try.


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## BoilerMan (Oct 8, 2012)

kopeck said:


> Seen these Taylor?
> 
> http://www.pexsupply.com/Webstone-4...Brass-Ball-Valve-w-Hi-Flow-Hose-Drain-600-WOG
> 
> ...


 
Hey for 16 bucks I'd buy one!  Webstone makes some cool stuff for the hydronic world.

TS


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## heaterman (Oct 17, 2012)

Morgan said:


> Nice install, the only thing I would like to point out is pipe with 1" pipe you are limiting yourself to about 90K BTU heat transfer, 1.25" would have allowed about 160K BTU, on the coldest days of the year you could be looking at 45K BTU's that are not being able to be delivered to the slab without over pumping the 1" pipe which would lead to system noise. Also why two relief valves? And your blue dope, is that rectorseal? Just started using it myself, I was a big leaklock fan but it has been letting be down lately.....mostly with coldstart systems, been getting drips, especially on my copper/brass threaded connections, rectorseal's non-hardening claims made me give it a try.


 

Good questions. As to the 1" copper and pex..........The Wirsbo Heat-Pex was existing to the job from the previous OWB that was installed there. It is buried and runs under about 15' of cement outside plus 30' of shop floor. No option to change it. That being said, even if I would have had that option I would not have recommended it in this case. It's simply not needed because the system inside the building can generate huge temperature drops. Along the lines of 30-40* so GPM required to move XX number of btu's is cut in half. You make an excellent point however that is very true in a lot of cases. 

The relief vavles are two different types for two different purposes. One is a standard 30PSI pressure relief, the other is a commercial grade T&P valve as you would find on a water heater. It is integrated into the system to be the emergency "dump zone" and it opens at 210* water temp. The boiler is connected to an automatic boiler feed valve so if the T&P valve ever opens, cold water is dumped into the system and the boiler is cooled off almost immediately.

The sealant used was Whitlams Blue Magic along with Loctite thread cord. Leak Lock is designed for refrigeration system which typically run all the time with little expansion/contraction. It's alcohol based and dries hard with little to no "give" for temperature swings. I have not had good luck with it either when used on boiler lines. Gas lines or under flare nuts, yes but not hot water.


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## Tennman (Oct 18, 2012)

HM, Pretty impressive. For my education, when I assembled my system all the published schematics showed the circ pump on the return near the boiler. There's been some discussions here lately about circ pump locations relative to the expansion tank. Is that the circ pump that's downstream of the separator (I'm assuming the standard exit at the top) and the boiler return line is hidden behind the boiler? BTW, the unit looks pretty elegant, but I'm surprised by the rather small lines. Small output boiler?


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## heaterman (Oct 18, 2012)

Tennman said:


> HM, Pretty impressive. For my education, when I assembled my system all the published schematics showed the circ pump on the return near the boiler. There's been some discussions here lately about circ pump locations relative to the expansion tank. Is that the circ pump that's downstream of the separator (I'm assuming the standard exit at the top) and the boiler return line is hidden behind the boiler? BTW, the unit looks pretty elegant, but I'm surprised by the rather small lines. Small output boiler?


 
The boiler circ is pumping away from the expansion tank and yes the return is just a short loop out of the floor and into the back of the boiler. There is also an air scoop/expansion tank on the primary loop inside the building.  The boiler will produce 135,000 at maximum firing rate but with a 30-40* drop being generated by 6,000 sq ft of radiant slab we only need to move 6-8GPM from the boiler to the primary loop. We have encountered no issues with overheating even when the demand from the building goes completely off. The boiler setpoint is about 176* and the highest I have seen it "coast" to is 190*. It shuts down very quickly.


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## heaterman (Oct 18, 2012)

DaveBP said:


> There is a certain beauty in simple design and a clean layout. At least to a certain type of person. I am one of those types.
> 
> I wonder though if it wouldn't look even more beautiful to the home owner's insurance agent with $10 worth of fire-rated drywall behind it in the corner. But I don't think it would add anything to the safety of the setup.


 
I agree on the drywall Dave but I was not in that decision loop, it's a good precaution. That being said , specified clearance to the back and sides is only 12" and we are past that all the way around.


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## heaterman (Oct 18, 2012)

I'm adding some more pictures to this thread of the indoor piping because it's a pretty good example of a Primary loop with secondary mixing done by variable speed injection.

This was done by someone else who is obviously pretty well versed in his trade. (Most definitely NOT the OWB sales guy that this customer had so much trouble with.)

Briefly; you'll see a picture of the Primary loop which is the 1-1/4" copper that runs vertically. To the left of that are the 3/4" copper lines that take 170-180* water from the primary and measure it into the radiant floor zones. (this is the injection loop and it is driven by the 15-58 with the motor mounted toward the wall)  The next progression if you will is the radiant floor main manifold. (3 Grundfos 26-64's) 

The little white box is a Tekmar 356 injection mixing control which looks at radiant manifold temp and outdoor temp, then calculates how much heat needs to be dumped into it to satisfy the heating requirements of the building. There is no actual building feedback other than room temp thermostats kicking the pumps on/off via the Taco circ control panel.

On the lower left of the primary loop you can see where we dump the boiler BTU's into the indoor system. There was a plate HX mounted there which isolated the previous boiler from the indoor piping. You can still see the outline of it on the plywood wall. As the new boiler is pressurized there was no need for a heat exchanger any more.

Fire away if you have any questions.

More pictures tomorrow of a really simple primary loop setup working with a gas boiler, an OWB and water heater we are doing right now.


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## heaterman (Oct 18, 2012)

Karl_northwind said:


> Looks nice. I have the literature and talked to marc extensively about them, and have been looking for applications. Could you use an ODR controller like a tekmar 256 to adjust the high temp automatically? A buffer tank would be necessary for most applications, but this one is really slick. Gotta love having high mass emitters.
> 
> am I missing something? why are there 2 PRV's?
> 
> karl


 

Karl.....I think I responded to your question about the 2 PRV's in the wrong thread..... Doh~

The relief valves are two different types for two different purposes. One is a standard 30PSI pressure relief, the other is a commercial grade T&P valve as you would find on a water heater. It is integrated into the system to be the emergency "dump zone" and it opens at 210* water temp.
The boiler is connected to an automatic boiler feed valve so if the T&P valve ever opens, cold water is dumped into the system and the boiler is cooled off almost immediately. The standard pressure relief is the one piped down to the floor, the T&P relief is piped out through the wall for obvious reasons.


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