My Varm project...

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Minister of Fire
Sep 15, 2011
Nova Scotia
I thought I would do this when it was done, but decided to get it going now. I'll see if I can stumble my way through all the pic posting and try to keep things in order & noted right. Pics are cell phone mostly, so some not the best quality.

I didn't take all the pics I should have. First big thing done was buying & bringing my tanks home. Meant to snap a pic of the pile I picked out of at the scrapyard, but this is the first one I have of them. Brought them home mid-May, wire wheeled & painted them, then took to welder to get fittings welded on. This is after that, patiently awaiting a few welding touch ups:

My Varm project...

Lesson: Try to make sure you dont get cast fittings.

Next big event was the day the boiler arrived:

My Varm project...

Lesson: Watch the exchange rates. I was doing that but had no choice than to buy when I did. Just happened to be when our dollar was at its lowest point in the past year. Soon as I decided to pull the trigger, down they want like a rock. Now they're back up. Uggh - likely cost me around $500.

Before shot of the boiler area. I should have taken a pic before I cleaned out under & around the steps. It was ugly, 17 years worth of ugly:

My Varm project...

Kijiji find - electric boiler for backup & circulator:

My Varm project...

First fitting splurge. Turned out to be a drop in the bucket:

My Varm project...

Lesson: Multiply fitting estimates by at least 4.

New 80 gallon electric hot water heater:

My Varm project...

Lesson: Should have got off the oil long ago. And these things are heavy.

Insulate the stair wall, 1.5" of foam board over 3.5" of fiberglass. Fiberglass was left over from the house build 17 years ago:

My Varm project...

Getting into things:

My Varm project...

Decided to try one of these mickey mouse crimpers:

My Varm project...

They actually don't work too bad once you get the hang of them & the vice grips set right. I'd get real ones though if I was going to be using them anything more than infrequently.

Expansion tank experiment:

My Varm project...

Have yet to see how good it will work. Sure as heck is cheaper than real ones.

Got tanks stacked. Man was it hot this day:

My Varm project...

And in they go:

My Varm project...

Lesson: when you ask your kid to help you, and he says soon as we're done swimming, just go ahead & do it yourself.

New boiler unpacking day:

My Varm project...

'Just put that thing on that stand'. Sure sounds easy enough - turned out to be kind of tricky.

But it got up there. And in it goes:

My Varm project...

I won't post the lesson there, I'll see if someone spots it. But I can't believe I did that - what a dummy.

Big week this week from skipping out on work a couple hours here and there. Filled the storage tanks with water - not one drip or leak (yes!), except for when I ran them over for just a few seconds. Got the oil tank pumped out (only got two jugs out of it - we were running on fumes) and old boiler all unhooked & up on a pallet & moved out of place, oil line cut & hole in floor patched & floor painted over, chimney swept for I hope the last time ever. Now all ready to go full bore on the assembly & moving the new boiler in place after another trip to supply store:

My Varm project...

Lesson: everything associated with this project is heavy. Thank god for levers, shims, dollies & pallet jacks.

That's where I am now - can't wait to get things together and light this puppy. Still have a ton of other things to do after that like insulating & covering the tanks in, then I suppose I should be getting my wood inside before it really starts getting cold. Darned good thing I started this way back in May. Will be more to come...
Awesome work Maple!

Definitely keep the pics/posts coming! Very excited to see how the rest of the install goes.

And I dont think your expansion tank is a fake one at all! They will work that way without a bladder, just try to make sure you have a way to add pressure in there if you need to....

And yeah, its NOT easy to get the boiler up on the stand. That was a real PITA for me.
Awesome work Maple!

Definitely keep the pics/posts coming! Very excited to see how the rest of the install goes.

And I dont think your expansion tank is a fake one at all! They will work that way without a bladder, just try to make sure you have a way to add pressure in there if you need to....

And yeah, its NOT easy to get the boiler up on the stand. That was a real PITA for me.

Plan A was to lift it by fittings screwed into the centre top hole. I got all ready to do that, then realized it was a 1" hole & I only had 1-1/4 fittings then. Crap. I managed to slip the forks in under the boiler, lift it off the pallet, let it down on the stand on some shims, then pry & wiggle those out. Wasn't much room to come & go on. I also took the ceramics out to lighten things up a bit.

You didn't spot the big 'aw crap' thing yet? It's stand related - still shaking my head about it...
Alright, I give up.
What is the aw crap moment?
Great pictures.
Fell like i'm watching an episode of this old house.
All I can say is :

Awesome pictures. Lots of work in them. Looks like lots more work to follow.
Keep the pics & progress reports coming :)
OH MAN..... now I hafta turn........ I mean......Awwwww Crap!

Close enough. In all the rushing around when I had the boiler teetering around in the air, I put the stand under it backwards. Never noticed until I had it wheeled inside & came back later to re-assess fittings. Wasn't going through that again so just dug out a small wire feed welder & welded a couple more pieces of angle iron to hold the ash pan, on the other end. Looks like it came that way now with some new paint in the right places. Didn't turn out to be a big deal but it wasted a couple hours.
So when do you think you will be able to have the first fire?

I would suggest bringing your wood in first and THEN insulate everything. I would want to get it all good and hot to see if any new leaks show up. Im hoping not, but you never know what will happen when things expand and contract some. Much easier if you dont have to pull wet insulation out of the way, or if its all sealed up and you cant see it. Plus any wood thats in your basement near those tanks gets to dry out a little bit more :)

I also put a five gallon bucket under the pressure relief for the first few firings until I get the loading based on the weather forecast down. The 22 PSI (or so) rating combined with not knowing how much wood it took to heat the tanks left a big puddle for me to clean up a few times. Plus I think I had overfilled the system to start, so it was the best way to make sure things got purged out. I still need to add a few more air vents to my piping.
Yes, wood first is my plan. It should have been in a month ago, it was a real dry summer now it's been raining a lot the past couple weeks. Have some inside left over from last year, tonights chore will be rearrange that & other stuff before I move my boiler into place. Will do insulation the very last - at least then I'll have lots of heat if I still have some things left to tie up on the distribution side.

22psi - that's not real high, I hadn't done the metric conversion on the valve rating. I had planned on the bucket, will make sure on that now. It will likely stay there too. I'm hoping now for first fire next weekend. With a big maybe.
Yeah, I think the Varms (mine at least) is rated to something like 1.5 bar that equates to 22 or 23 PSI. I have a LOT of expansion tank, and even with that I had some weeping the first few times I pushed my storage up over 190 from top to bottom. Since then I have purged some air (and water to go with it), so my pressures are way down to start the season. I may just fire the boiler up with my punky stuff to get some heat in the tanks and see where the pressures go before I add any more back into the system.
What was your cold start PSI? And are you heating one story or two?

I think I was aiming for 10 psi, but then I realized the gage was broken on the oil boiler, which is what I was using. Heating two stories.

Plus I filled my system from the bottom of the tanks via a hose bib to help with air purging. So the autofill valve didnt help.

I would say dial your fill back to the minimum (10 psi usually) to start and see if your circs are ok with it that low.
The lower the psi in the system, the better to use "pumping away" piping scheme. Install all circulators on the supply and keep all piping on the big side to avoid cavitation.

Taylor is right. the lower PSI can be bad for pumps and air entrapment in the piping. Im currently not set up that way (used the previous pumping scheme that was in the house) and I was OK this past year, I think. But if I had it to start from scratch, I would definitely put my circs on the supply side, and the expansion tank before the pumps. Right now Im the opposite of both of those things :(
I just plumbed in my load circ, and it's on the return down low. I do have the expansion tank just upstream of the circ - just finished airing it up to 10 PSI for now, hope there's no leaks as there was quite a bit of jigging around getting the new piping lined up with the expansion piping which has been sitting there since July. Had to take a bit apart in a real tight space & put a shorter nipple in to finally get it lined up right. My back is starting to flare up after all that.

Actually, isn't the loading valve (laddomat) unit & circ also mounted on the return side and low? Actually in every picture or diagram I see I think? So isn't that contrary to 'circ on supply' thinking?
This is the worst way to do it Maple. Go to heating help and search for "pumping away" and you'll see why. If the expansion tank is upstream of the circ. the circ's head pressure compresses the air in the exp tank lowering the system pressure even more before the circ making flash boiling more likely in a lower pressure situation like a 10psi start up.
Think about it this way, if the circulator is pushing water into the boiler, it is also pushing water into the expansion tank. Now the pressure is lower in the piping after the expansion tank connection in the piping, and that lower pressure is all that is relied upon to bring water bask to the circulator.
Now move the circulator to the supply after the expansion tank connection, and it's head pressure is pushing the water through the heating circuit, adding to the static pressure of the system. Water can't be pulled by anything ever! It is only pushed be the pressure in the system to the circulator's inlet volute.
That pressure feeding the circulator what is left after going through the whole heating circuit and after the expansion tank, or from the large low loss boiler and the expansion tank is just absorbing the difference in water volume from the heat.
I hope that made sense to someone other than me.

Best way:

Boiler, expansion tank, at least 5 feet of pipe, circulator, check valve, heating circuit, (alternate check valve location), back to boiler. Pumping away = pump head pressure+ system static pressure.

Worst way:

Boiler, check valve, heating circuit, circulator, expansion tank, back to boiler. Sytem static pressure - head loss of heating circuit.

The old adage of the circulator lasting longer due to being cooler is no longer true, it was back in the day of mechanical seals in circulators. With cartridge circulators with wet rotors, there is no longer a seal to fail from heat, and the motor is made for 240F+ fluid temps.

Too late in the day for me to think more about this - I'll try to do some tomorrow.

But when I say the expansion is upstream of the circ, that means it pulls from the expansion tank when it pushes into the boiler. (And also pulls through the zones from the top of the boiler?). Simply put, following the flow backwards (upstream) from the bottom of the boiler, it goes boiler, circ, then a T to expansion one way and the zones the other way back around to the top of the boiler.

I don't know - that's the way my current system was hooked up for 17 years (circ on the return of the boiler) and it ran like a top - just that the boiler was, umm, a less than desirable performer.
Taylor has described the pumping away concept pretty well. But you are OK for the most part since your expansion tanks are before your circs. Im set up the worst way on my oil boiler, circs ahead of boiler, expansion after.

You are right as far as the storage goes, that the laddomat is on the return side, but if you just look at the little mini loop between wood boiler and storage, there isnt really a good place of no pressure change to add expansion. I just have my expansion tied to my storage and called it a day.
I don't know - that's the way my current system was hooked up for 17 years (circ on the return of the boiler) and it ran like a top - just that the boiler was, umm, a less than desirable performer.

Old air-tight wood boilers worked too, but gassifiers work better.
It worked, but now your dealing with wood, storage, higher temps, higher flows, than the old oil boiler, and a lower system pressure, all adding up to more of a need to pump away. Don't get me wrong you can do what you want, it's a free country.....and your in Canada....... Anyhow, pumping away on the supply of a wood boiler just reduces the risk of flash boiling water in the pump volute, and cavatation or micro-cavatation causing pump impeller degradation, it also and makes air elimination better, and makes the best use of the pump's wattage. Just what I've been told by those who are in the know on these things, and if one thinks about it, it makes a lot of sense.

The old boiler is wood & oil both, so I've been burning wood and the system has been dealing with wood heat since the house was built 17 years ago. I do realize that a gasifier will put out more heat that my old one (darned well better after all this), but I've also got all that storage now and a fancy laddomat thing to move the heat to it - so the distribution sytem itself shouldn't be seeing higher temps or flows than before since it will be drawing though storage. I had some fairly hot events with the old one over the years - waking up to rumbles in the basement because the draft door hung up for some weird reason is kind of un-nerving. System pressure on it was about 12 cold, and I don't think it ever went over 20 - that's kind of what I'm hoping to see with this setup too.

I also made sure to plumb the expansion so that it comes in on the suction side of the load circulator - which is what I meant when I said up stream from the pump.

I will definitely keep the pumping away in mind if things turn out to not work quite the best - at this point I'll be trying what I have hooked up first, then if changes are needed I'll make them. I'm sure there will be some wrinkles along the way. Or I should say more wrinkles.
A guy at work told me the same thing about pumping away, though my 7 year old oil system was plumbed the same as maple's. I guess there's a lot of inertia among installers.

Also, I think maple is replacing a working wood/oil boiler
Ok, I see what you mean now Maple, your not in the worst way if the expansion is on the suction side, thats all that really matters in the whole concept.....
I guess there's a lot of inertia among installers.

You wouldn't believe how many people still think that leaving a car battery on the floor somehow ruins it or discharges it. When I was a mechanic, customers would sass me all the time for setting their battery on the concrete shop floor while I was working on their car.........