My first Outdoor Hydronic Furnace build....OHF

[brenndatomu]

Totally off topic, but quick question for those familiar with Polar...a coworker is looking to install a OWB and found a 2YO G2 for $8k, it sounds like the owner figured out that "free heat" still means some work, so going a different way for heating.
This seems like a pretty good deal to me...anything to watch out for on those?
Too big for heating a 2000 ft ranch (both main floor, and basement apartment) and a 3 car garage/shop?

 

[cumminstinkerer]

Totally off topic, but quick question for those familiar with Polar...a coworker is looking to install a OWB and found a 2YO G2 for $8k, it sounds like the owner figured out that "free heat" still means some work, so going a different way for heating.
This seems like a pretty good deal to me...anything to watch out for on those?
Too big for heating a 2000 ft ranch (both main floor, and basement apartment) and a 3 car garage/shop?

no sir that boiler would be good for that, and the price is good, check the turbulators to see if they are stuck, not a huge deal breaker though, check the door ceramic on the reaction chamber, it is a wear item, I'd make sure the fan functions as it should as well as the actuators for incoming air on the intake manifolds

 

[brenndatomu]

no sir that boiler would be good for that, and the price is good, check the turbulators to see if they are stuck, not a huge deal breaker though, check the door ceramic on the reaction chamber, it is a wear item, I'd make sure the fan functions as it should as well as the actuators for incoming air on the intake manifolds

Thank you sir!

 

[cumminstinkerer]

my house is around 1300 sq feet, basement is the same and also heated, not the best wall insulation but the attic is good now, I run a G2+ but I also do DHW and have the 1500 insulated storage too but I have no issues

 

[sloeffle]

I did note that most gassers I've paid notice too, pull off the top and return on the bottom. I always figured it was because the hottest burn is at the bottom of the stove. Pulling from the top and returning to the bottom theoretically should mix the temps very well.

G4000 pulls from the bottom and returns at the top. Not sure where the piping goes inside of the boiler. My guess is the supply pipe inside of the boiler pulls from the bottom of the boiler via piping inside the boiler. Both pumps run 24x7. Pump on the left is a shunt pump to help mix the water as @brenndatomu posted about.

This is a picture of the back of my boiler before I insulated the piping. Used 1" heater hose between the underground piping and the fittings so the boiler can move independently if there's frost heaving under the pad. Don't skimp out on underground piping. You should lose very little heat between the boiler and the building(s) its heating.

 

[Tonty]

My firebox is towards the top of the storage, and my supply pulls from right above the firebox on the top front of the boiler. With the way the flue gas pipes pass through the water storage, I think that makes the most sense on mine. The return is on the bottom in the back. I run a pump 24/7 because I don't want my storage to stratify when not burning. If I'm going to be gone for a couple of days, I will turn the circulation pump off since in that scenario I do want it to stratify.

 

[all night moe]

G4000 pulls from the bottom and returns at the top. Not sure where the piping goes inside of the boiler. My guess is the supply pipe inside of the boiler pulls from the bottom of the boiler via piping inside the boiler. Both pumps run 24x7. Pump on the left is a shunt pump to help mix the water as @brenndatomu posted about.

This is a picture of the back of my boiler before I insulated the piping. Used 1" heater hose between the underground piping and the fittings so the boiler can move independently if there's frost heaving under the pad. Don't skimp out on underground piping. You should lose very little heat between the boiler and the building(s) its heating.

View attachment 346195

Interesting that your supply and return ports are somewhat close together. Like you said though, piping inside may be a different story entirely. I love the fact you used heater hose for final connections. Not only do you have flexibility for movement, It must of saved you a deal of hassel with connections.

 

[salecker]

I dunno about Polar, but I know Heatmaster G series has a small pump mixing the water in the boiler 24/7

I have the near boiler pump for boiler protection, but once the temp is satisfied it no longer is in play. I can't see any advantage to have it run any longer , but always open to new ideas.

 

[all night moe]

I plan to run my circulator pump 24/7. Going to go with a big 3spd Grundfos.

Don't skimp out on underground piping.

Oh, no worries. I've done my research. There's a Logstor dealer 35mins from here. There's a Thermo-pex dealer little over an hours drive.
A friend has the Logstor and said it's metric sized, which is a pain since no local suppliers carry any metric fittings. He can just replace anything faulty without traveling. I'm hoping Thermo-pex is SAE.

Along with that big pump, the insulated lines will be 1 1.4''. I remember reading several hints to bigger is generally better here.
My run is 170-180'. It's also going up a small grade to the house. I have a good plan for my interior plumbing but, I'll save that for later.
I will note, once inside I'll have a second pump zoned for the second floor. 1'' PEX into the attic and run a 3 pipe loop, supply and return. I will drop down into the rooms for cast iron rads. All plumbed with thermo-valves.

Boiler pump will be on it's own closed loop, feeding an 90 or 90 FPHE with the same size ports on the boiler side. The boiler should see good circulation.

 

[sloeffle]

I plan to run my circulator pump 24/7. Going to go with a big 3spd Grundfos.

Via head pressure calculation I could have gone with a smaller pump and ran it on high. Spoke to a couple people and they said the Grundfos 26-99 is a tried true pump for OWB applications. I run my pump on medium speed, and I have around a 15-degree delta T across the HX in my furnace. I've ran it on high and low haven't noticed any kind of difference in heat delivered to the house. The 26-99 Alpha's are very nice pumps too, but they are about double the price of standard 26-99. I can buy a lot of electric in my area for $300.

Long sweep 90's are your friend too.

 

[all night moe]

Via head pressure calculation I could have gone with a smaller pump and ran it on high. Spoke to a couple people and they said the Grundfos 26-99 is a tried true pump for OWB applications. I run my pump on medium speed, and I have around a 15-degree delta T across the HX in my furnace. I've ran it on high and low haven't noticed any kind of difference in heat delivered to the house. The 26-99 Alpha's are very nice pumps too, but they are about double the price of standard 26-99. I can buy a lot of electric in my area for $300.

Long sweep 90's are your friend too.

All noted, and thank you.
All lessons learned here are beneficial in savings. I don't want to plumb stuff twice. Tis why I'm doing the DIY boiler. So my initial investments can go into the plumbing system.

Reading on the Logstor, I may just go with it. Making comparisons to Rehau and Thermo-pex now.

 

[salecker]

I ran 4 runs of 1" Rehau as the 1 1/4 was very expensive and had to be ordered in to the Yukon
I asked for 6" of foam around the lines.
My first foam guy dissapeared and had to find another at the last minute. my timing was for good weather but when the 1st guy ghosted me all plans went out the window

 

[cumminstinkerer]

Y'all will flame me for this but all my lines are 1 HDPE black water line, rated at 160 so the thick wall stuff! been in service for the better part of 10 years and no issues that wasn't me dinging one with something, only the ones in the garage are exposed, the underground is wrapped with R14 fiberglass glass bat, one full wrap around one pipe the another around both, taped about every 6 feet, then inside a 4 sch 40 pvc that is all glue jointed, it was way cheaper and has no measurable temp drop, it is about 75 feet total each way from the garage exit point to house entry and I cannot get any temp monitoring device to register any drop from one building to the other!

 

[sloeffle]

The key to homemade lines is keeping the water out. Once you have water intrusion, you are screwed.

 

[cumminstinkerer]

The key to homemade lines is keeping the water out. Once you have water intrusion, you are screwed.

YES SIR! fighting trying to prove that to my father now, I will get get proven though, good insulation helps a lot but water is terrible, even on top of hill with clay a foot down where we both are you will still get water! I did field tiling and dirt work as a full time job for 8 years, so I know water has its own mind to a degree