Help with OWB, is my pump right?

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Can you verify the owb guage is reading right? With an IR gun, you can usually get a reading on the fitting it's screwed into. Might have to spray a spot of paint first. But we also don't know if your IR gun is accurate.

If the OWB guage (which is in the upper part of the boiler) is right, and you only have 142 water at the bottom, that means you do not have enough flow through the boiler. Even if the aquastat is out somehow, playing with the aquastat won't make the water at the bottom get much hotter. It needs flow through the boiler to make that happen. I would not mess around any more with the aquastat until you get temps at the bottom closer to what they are at the top. The aquastat could be in a hotter part of the boiler than the guage.

I am leaning to plugged HX, but we still don't know what you did when you 'bypassed' it.
 
I never bypassed it.
Could thru boiler drains i suppose with a washing machine hose.
 
What kind of water temp do you get when the oil burner is running?
 
I never bypassed it.
Could thru boiler drains i suppose with a washing machine hose.

I could swear I read you say that you tried bypassing the HX, but don't see it now.

But if you didn't, and you can - then you should. Bypass it, and see what that does do your bottom of boiler temp & temp of water leaving the boiler. Need to make sure there is no flow through the oil side of the hx while doing it though. Not sure when you want to do that - you will be without any heat from the OWB while trying. But if the oil is free to kick in, no biggie.
 
I really want to backflush the heat exchanger with a hose. Have to cool it tho as not to shock it correct?
I can play with all this tommorow am.
Dont really feel like interupting heat at night.
 
If the HX is plugged, you will need to flush it with more than water. Some have used CLR OK, but you will need to recirculate it for quite a while. Some found CLR didn't work, and used an acid, and even then had to recirc for a while, or let it soak for a while. Forget exactly what right now - I want to say muriatic, but that might not be right. There are other threads around about it.

After a bit more of bouncing this around in my head, you just simply may not be able to flow enough water around your loop to meet the design flow (8gpm) through the boiler, with the undersized pipe. But you may be able to flow enough to heat your house, if the supply was hot enough. I think someone else suggested adding another pump (could maybe use your old 0010) and a bypass loop, that would recirc through the boiler. Pump from top, into bottom. Failing upsizing your underground, it may come to that. If you have extra ports on the boiler, or can T into other ones. One spot might be the boiler drain on the bottom, not sure about up top. Then you would get hotter water at the bottom for your loop pump to draw from and your boiler wouldn't idle as much.
 
I plumbed extra ports on the back of the boiler in case i decided to add the garage. Could use this as a loop circuit if needed.
Today the wind was howling and the heat was doing something, the apartment went up to 58, the house stayed at 56.
I feel as though cranking the aquastat put the water temp up hot enough that the house could pull it down.
Feel thats why the heat is stalling in the house. Its not hot enough to have enough differential to go higher then 56. It doesnt go lower, so its not.lack of btus. If i was lacking btus, it would surely be going colder at 4 degrees with a 20mph wind.
But it doesnt. It maintains perfectly.
Rather without high temps, it cannot reach the target thermostat setting.

I have snow on the ground and no melting above the pipes, so i feel confident that the pipes not bleeding off heat.
 
No snow melt is no guarantee. Measuring of temps at each end of each underground tells that tale. But we seem to be having temp measuring issues.
 
So it's struggling to reach temp and it maintains perfectly. That's 2 opposite things. And high winds will be more likely to overheat the boiler. Did you say that you had seasoned wood? I can't remember.
 
Struggling to reach the target thermostat setting of 60 is the issue. But it will maintain 56 all day and night. Lacking btus would pull the house colder as the temp went down and the wind picked up would it not?
Wheras water that is too cold will maintain a certain temp, but never get any higher.
I raised the aquastat today and the house got warmer.

Im not stupid, im highly inteligent with ADD. I will try everything i can think of while trying to find the problem.
You guys are saying flow, i just increased the flow 4-5 times(0010-0013) and i have the same issue.
Im saying temps and you guys tell me.my.data is wrong.
Ive measured everything 10 ways to sunday and yet im still not giving you enough data.
The teacup data is the same thermometer at every point i can give you.
The fact that the data says the temp.is.low means the dam temp is low.
Im also pointing the finger at the aquastat because it doesnt maintain the proper range. It has a wheel in the back, i can change the temp spread from 35-5 degrees. So if 185 setting, furnace should run 150-185. Thats where it was last week 35. Ran 150-170 on front gauge. Turned the rear dial to 5. Should now keep boiler 180-185 and fire very often to do so. It doesnt. Been running 160-170 front gauge. Firing once per hour.
Turning the aquastat up to 190 forced the boiler to run all day and i never saw better then 170. But the junk gauges read 80 at one point, highest theyve ever read. Ran 74out 70c in most of the day.
The dam plumber told me the pump was going the right way. Funny, i reversed it and got 130 on the oil furnace gauge, 10 hotter then it ever read before.
Actions speak louder then words.
At this point if i thought the 2400-45 would fix the problem, i would buy it. But i dont see it fixing it.
Theres something wrong.
May just crank that dam aquastat to 200 tommorow just to prove a point.
Theres a 200 degree high limit aquastat right next to it...and i havent hit that yet. Makes me think this one is junk.
None of you have ever seen a aquastat fail??
 
Yes stats can fail. Watching what the draft damper or draft fan (whichever yours has) does and when will tell if there is a stat problem. Don't think we've heard about that. And, putting a more capable pump on does not mean your flow increased much if your hx is plugged or your pipe is too small or if there is air trapped.

But you have also said, I think, more or less, that the boiler is hot on the top and cold at the bottom. That means there is not enough flow through the boiler, plain & simple. And the supply draws from the bottom, whereas the stat is up where the hot stuff is. Maybe you could call the boiler manufacturer & see what they have to say about everything.

But wood quality is also something we know nothing about, and also plays a part in how much heat you get.
 
Wood is all over the place. Burning seasoned oak with a few green sticks on top for the night shift, seasoned pine and dry lumber in the am mixed with some oak, then added some apple this afternoon. I tend to save my.good stuff for night or crazy cold. I actually get the hottest temps from lumber, mostly because its such a hot fire it takes longer to bank and then cool.
Telling me i should do a raging lumber load in the am???
 
Oh yes. Turning up the main aquastat on a open loop boiler with a high limit switch set to 200 and 142 degree water. Roll eyes.
You have no idea who your talking to and what i do. This boiler doesnt scare me in the least.
I could weld up my own boiler if wanted to.
Done it all, heavy equipment, sawmills, electricity, plumbing. Even commercial firework shoots. Bet they dont let you play with 6" mortars at work.

So question. You guys all concerned with your flow, want me to time filling a 5 gallon bucket. I havent done this because i dont think it will measure the pumps flow correctly. In order to do that right, i would need a shutoff on the owb return and a boiler drain before it.
If i try to fill a bucket in the basement gravity is going to help the pump, guess we could do it on the out side of heatx and see if theres restriction.
Thoughts? Still not right, only half the pex to flow through.
I get what your saying about flow and mixing. But the pump didnt really make ANY difference. Barely even knew i changed pumps besides being able to feel current inside the pipe. Didnt affect the boiler temps. If it was flow, going 5x what i had should have stirred up the boiler.
UNLESS the heatx is fouled.
What if i time 5 gal bucket fills on the in vs out side of the heat x on wood side.
I dont think the oil side will have a issue, it was always wet, but the wood side very well may have boiled dry when she heated a whole winter with no pump or boiler connected outside. And that would leave a heck of a deposit with this towns water.
 
So how long should i bypass heat x for tommorow to see if it makes a difference? 15 min, longer?
I will conduct some more tests in the am. Maybe do 5 gal bucket draw down first thing while shes cool(140ish by front gauge)add some water
Then let it recover...then bypass for a bit, see what temps do....for a bypass scenario, im thinking oil side pump off, valve closed,
And a washer hose from boilerdrai nto boilerdrain helping the flow out, should see a diiference if it was plugged, possibly hear a difference in pump.

Whats really weird is, guy on hearth site has a 0013 on 300'loop of 1 pex and his pump is noisy as hell cavitating...mine just humms along.
Wonder if theres a crazy voltage drop on 125' of 12/3?
Shouldnt be, line voltage is crazy high on this road, but it was a thought.
 
Actually, on second thought, i should teacup test the water first thing at the pump on owb and see what it is when the front gauge says 140 and the firebox is no more then coals. Be interesting to see if its 140 or 110.
 
If you want to do some kind of timed bucket fill, you should fill the bucket from the boiler return line just before it enters the OWB. Then you will be catching flow from the whole loop.

I don't think you are taking fully into account how much that design flow through the boiler is needed. The boiler manual I read, spec'd minimum 8gpm. That is needed, to move the hot upper water, to the bottom where the supply line can move it out from - since the boiler supply line is on the bottom. I suspect the old OWB had the supply line at the top. A huge difference in boiler design. It might have been heating the house OK under the same loop flow conditions, with less flow through the boiler. You actually have 2 design flows here to get right - flow through the boiler to get the water mixed & hot enough water to the bottom of the boiler, and the flow through the loop which determines how much heat goes to the house. So, if you are developing your flow with just the one pump and the whole thing is one loop, that pump might be capable of pumping enough GPM to your HX, but not enough flow to get the boiler water mixed. The pipe size and length might not be capable of flowing that 8gpm with that pump - in which case you might need to add a boiler bypass loop with a second smaller pump. And if the HX is dirty, it won't matter how big a loop pump you put on there. You need to rule individual things out, one thing at a time. First is the HX. 15 minutes should tell - but your boiler should be up to a stable burning temp first.

If you are getting tired of our input, I would seriously advise calling Heatmor.
 
Actually maple, quite the opposite. I respect your advice and that of Oxford.
until he started being all whiny and saying i wasnt going to do things.
So between my aggrevation with a problem that shouldnt be this hard and his antics, i went off a bit.
I get what your saying about flow and loops.
 
This morning, nothing but coals, front gauge said 110, got 110 degree water from the back
 

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