New MPO installation - FINALLY!

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  #161  
Old 12-30-12, 07:34 PM
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Always better to have a high class POS.

This has been a great thread to read. It's amazing the sh*t we get involved in.....in the name of science.
 
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  #162  
Old 01-15-13, 03:47 PM
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Trying to find your by past post with your test...

I know you did a boiler by pass and tested with a system bypass.... but, I would have to ask,,,,why did you not do P/S piping from the beggining?

Or then again, what is the best way?

boiler/system by pass ,
three or 4 way arrangement,
or primary secondary pumping (with a bypass) This is the #1 prefeered I assumed...
or ESBE.
 
  #163  
Old 01-15-13, 04:30 PM
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That 'experiment' with the bypasses was in somebody else's thread... I don't remember where either.

Here's what I have PIPED, can be seen by looking back at the pics, but save the trouble, I'll describe:

All the piping from boilers to manifold in 1" copper.

There is a full size boiler bypass with globe valves.

The 'test' that I did was with a WASHING MACHINE HOSE, from the drain on the supply manifold to the drain on the return manifold. The I.D. on washing machine hoses isn't even as big as 1/2" copper.

Here's what I feel is the problem with B.B. on MY system.

Because for the great majority of the heating season I can heat the home with 150 or LESS water temps, running the boiler bypass results in much cooler return temps than I would like to see because boiler bypass works by slowing flow through the boiler and making the SUPPLY HOTTER. The RETURN is what it is.

With the BB in operation, my return temps are RARELY over 120, and MOST of the time, well below that. (If for example the SUPPLY temp is only 140, and the BB gets me a 30 delta T)

It just isn't giving me that "warm, fuzzy" feeling.

Enter the SYSTEM BYPASS test.

With the wash machine hose hooked up and valves open, a typical heat call might run to 140 SUPPLY temp. Even with this small hose, my RETURN was running at 130. Even if the heat call is satisfied with 130 SUPPLY, I'm still looking at 120 returns. (I am seeing a 10 delta with the small hose bypass)

I feel MUCH better about this, and I can not notice any difference in the responsiveness of the heat in the home. After all, that hose just looks like a third zone opening on the system, and the 15-58 G'fos is more than capable of running 3 zones.

It seems (my observations, no measurements) that the boiler heats FASTER with the system bypass and that the ENTIRE boiler is heating a bit more.

What would be ideal for MY system? Or, what would I prefer best?

Probably an ESBE at 115 on the return side. With the thermostatic valve in place, EVERY HEAT CALL would warm the boiler above the condensing point. Remember that oil dew point is said to be 115, and this is the temperature that the ESBE STARTS to open. I believe it is 'all in' at about 130 or so. Therefore, a heat call from the thermostat can not end early.

Yes, I may burn a little more fuel... but save the boiler. I think I want to save the boiler at the cost of the fuel.

I didn't do P/S because I didn't want the extra pump and controls. KIASAP.
 
  #164  
Old 01-15-13, 04:34 PM
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Caleffi makes a nice looking thermo bypass valve too!

http://www.caleffi.us/en_US/Technica...1223/01223.pdf

Haven't really found a source for them yet. They are a bit pricier than the ESBE.

I like the fact that there are union connections and would be much easier to 'cut in' to an existing install, unlike the ESBE FNPT connections only.

Both have easily replaceable elements.

And check out the neat little 'thermometer wells' on the valve! How thoughtful of them! (they just want to sell you the optional thermometer!) But still, great idea!
 
  #165  
Old 01-15-13, 04:36 PM
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The other option if you like electronics...

Taco iSeries valves. A 2 way model in the bypass line set up in the 'setpoint' mode. (almost $300)
 
  #166  
Old 01-19-13, 08:41 PM
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What are you worried about return temps for? The MPO can handle 100f and not condense. I actually found the first MPO condense. It was running radiant with 100f out and 70 f back. It stopped condensing when the return got to about 90f.
I have mentioned many times here that the return temp is not as important as the volume of cool water. It is the ratio of cool water compared to the water capacity of the boiler. The flow is more important that he temp thus the need at times for boiler bypasses. Many boilers the flow is too great. Every boiler has a min & max flow rate. Do the math to determine flow rate. The MPOIQ-84 should be between 4 & 8 GPM.
Also remember that a boiler bypass means the flow rate in the system is higher thus higher output from the radiation. Speed up flow equals more heat less flow equals less heat.
 
  #167  
Old 01-19-13, 09:06 PM
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I dunno rbeck, call me a cynical skeptic I guess!

I haven't opened the door lately to look, but I DID see signs of condensation earlier in the season when I opened it for a peek.

I guess I need to take another look-see inside.

I can tell you this much though, it RAINS inside the chimney... whenever it runs.

The baffles are removed.

The temp at breech runs around 380 at the end of typical heat call, which usually ends with supply temp between 140 and 145.

By the time the flue gas gets to the chimney base, the temp is NEVER above 200F ... I know that it's WELL below 115 by the time it exits at the top. The bottom of the tee at the bottom is ALWAYS full of condensate.

This is of course a different issue than condensation INSIDE the boiler... and I've got plans to take some steps in the spring to rectify this as much as possible. ( the 5" SS insulated liner, etc...)

Back to condensation in the boiler:

OFTEN the heat call ends at 120... and naturally, the return temps are BARELY breaking that 100 mark. I'm SURE there are times the boiler is 'put up wet'. It's these periods during the shoulder seasons that I am not comfortable with.

I can't think of a reason NOT to use a system bypass on my setup...

I don't really see a 'down side' to it on MY system.

I measure the delta T on the two heating loops with the makeshift washing machine system bypass CLOSED and come up with very close to 20F.

I open the makeshift system bypass and the DT on the loops is STILL very close to 20F.

So, I'm not losing flow in the system. The small bypass just looks like another zone to the circ pump... it can handle the two 3/4" loops AND the bypass just fine...

I can't see it being less economical... I'm not 'losing' any heat just because the return temps are a little higher...

Like I said, just skeptical is all... exploring all things.
 
  #168  
Old 01-20-13, 06:09 AM
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Is the delta tee in the boiler 20 f?
If so the reason for a boiler bypass is to control the delta t in the boiler using flow not return temp. Remember the system efficiency is the $$$$ saver. A boiler bypass will allow you to slow the boiler flow thus getting the boiler temp a little higher. The point of boiler bypass is flow and average water temperature not entering water temperature. Enter water @ 100f with a 20f delta exit at 120f. Average temp 110f. Enter at 100f slow flow to a 30f exit @ 130f average is 115f. System temp does not change so system efficiency is still high and heating less gallons. What are your ODR numbers?
If you notice in the MPO manual there should be a chart that shows minimum flows for lower water temps.
 
  #169  
Old 09-27-13, 03:58 PM
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I'm going to add a bit onto my thread in regard to the chimney liner I installed, just to 'close the loop' a bit.

To recap, my 6" double wall manufactured chimney was literally 'raining' inside every time the boiler ran. I had to keep a bucket under the tee fitting at the bottom of the chimney to catch the condensate before it ran all over the floor.

The new boiler has a 5" outlet, and I ran 5" to the base of the chimney and adapted to 6" at that point.

I had to add a NPP (Neutral Pressure Point) plate to the flue pipe to keep the draft at the boiler breech within spec.

It was deduced that the reason for the rain was because the flue outlet temp was already lower being a high efficiency 3-pass boiler. It was around 340 or so. By the time the gases got past the barometric damper, which was open quite wide because of the 'extra' air it needed to pull in order to 'fill' the 6" pipe, the temperature 6' further up the flue as it entered the chimney was under 200F. By the time these already diluted and cooled flue gases got to the top of the chimney, they were cooled well under 100 I'm sure.

I was going to install an insulated, solid, 5" rigid stainless liner... but after discussing with technical help at Chimney Liner Depot - Buy Flue Liner and Save Big, DIY Chimney Repair and rbeck it was decided that a FOUR INCH Flex-King Pro liner would be the way to go.

Four inch was decided on for a several reasons...

1. It's big enough to carry the volume of flue gas.

1a. NFPA allows one pipe size reduction.
1b. My local code enforcement inspectors allowed it.
1c. My Burnham 'go to guy' said it was OK.

2. Smaller liner allowed 0.5" insulation blanket vs. the 0.25" I would have had to use for the 5" liner to fit inside the 6".

3. Smaller liner would require less air into the flue via the barometric damper, thus would dilute and cool the gas less.

4. The VELOCITY of the flue gas in the 4" would be much faster than in the 5" and thus less time for the gas to cool before it reached the top of the chimney.

The liner was installed last month. It was pretty easy...

I re-installed the 3rd pass baffles that I had removed last winter to boost the flue gas temp.

Initial testing showed that re-installing the baffles dropped the FG exit temp about 30 or so, and yet the temperature at the base of the chimney went UP about 50 due to less dilution air from the baro damper.

The DRAFT at the boiler breech is UNCHANGED. Remember that I had added a NPP adapter to control breech draft... and first testing had the NPP REMOVED. I had to RE-INSTALL the NPP because the draft at the boiler breech was still too much. Putting the NPP back in brought the breech draft back to where it was previously when feeding the 6" chimney without the liner.

So far, with the weather still warm, the baro damper remains closed when the boiler is firing. I expect that as it gets colder out, it will have to open a bit... that remains to be seen.

I sure hope that this cures the rainstorm in my chimney!

I wish that I had thought to install a thermocouple in the pipe LAST YEAR so I could measure the temp at the top of the chimney and compare to this year... and that I had installed one THIS year too... but I didn't... so I will have to go by the amount of rainfall in my 'bucket under the tee rain gauge' I guess.

That is all for now! Perhaps more as the weather gets colder... Happy Heating!
 
  #170  
Old 09-27-13, 06:39 PM
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I wish that I had thought to install a thermocouple in the pipe LAST YEAR so I could measure the temp at the top of the chimney
That would be very nice, for sure. I don't have a high-efficiency boiler. I just go by the appearance of the plume at the exit of the chimney on a cold day, after the chimney has had time to warm up. If the flue gas is visible immediately at the exit point of the chimney, it is less that 212 deg - not good. If it is invisible for the first few inches above the chimney exit, before mixing with cold air, it is above 212 deg - good.

Watch the exhaust plumes from autos on a cold day. Initially, they will be totally saturated with water vapor and display a completely visible plume. After driving a few blocks, the initial plume from the tail pipe will be invisible, only appearing a distance from the end of the tail pipe after mixing with cold air.
 
  #171  
Old 09-27-13, 07:17 PM
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Last years plume from the chimney was INTENSE! It was always 'overcast' in my yard. It would rise up and form CLOUDS! (ok, I'm exaggerating... a little! ) There was absolutely ZERO distance from the top of the chimney to the start of the plume. I've convinced that the plume started down inside the chimney, probably 5 or 6 feet down at least.

That's also why every other year we had to put a new exhaust system on Grandma's Nova... she never drove more than 3 miles and all that condensate trapped in the exhaust system rotted it out!
 
  #172  
Old 09-28-13, 10:19 PM
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That MPO looks great!

Very nice work Troop! That MPO found a great home and owner. ;-)
 
  #173  
Old 09-29-13, 05:59 AM
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WHO! My goodness it's been a long time! Drop me a PM and tell me what yer up to!

Thanks for the kudos... it was fun... and a long learning experience! How long had I talked about doing this before I pulled the trigger?
 
  #174  
Old 12-27-13, 04:32 PM
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That is all for now! Perhaps more as the weather gets colder... Happy Heating!
So far, so good with the new liner installed. No signs of any condensation at all.

New boiler will probably pass the 1000 hour mark tonight. Looked at the meter about an hour ago and it was at 998.9 hours... That's about 600 gallons of oil for last year, and so far this year. Jeeze... to think that I used to get about HALFway through ONE heating season on that much!
 
  #175  
Old 12-27-13, 05:21 PM
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That's about 600 gallons of oil for last year, and so far this year. Jeeze... to think that I used to get about HALFway through ONE heating season on that much!
Are you saying that you bought 600 gallons last year and are still using it?
 
  #176  
Old 12-27-13, 05:51 PM
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Are you saying that you bought 600 gallons last year and are still using it?
Probably droo... You know troop keeps his t stats at 55f............... Pinch a penny when you can....
 
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Old 12-27-13, 05:55 PM
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I do 600 gall/year on my 20 year old Ultimate w/tankless coil heating just under 2000 sq ft.
 
  #178  
Old 12-27-13, 06:07 PM
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Are you saying that you bought 600 gallons last year and are still using it?
No... I've got a 275 gallon tank!

That's just what I've burned, multiple deliveries.

Firing rate is 0.6 GPH X 1000 hrs.

Thermostat is on "HOLD" at 70 I can squeeze a $5 bill so hard I make Lincoln cry, but I'm nice and warm while doing it!

When the treasurer gets chilly, I bump it to 71

I'm also just under 2000 SF Tom, and when I moved here in '84 I used to burn 1000-1100 per year! LOTS of changes to 'This Old Box' in the past 30 years!
 
  #179  
Old 12-27-13, 06:16 PM
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Thermostat is on "HOLD" at 70 I can squeeze a $5 bill so hard I make Lincoln cry, but I'm nice and warm while doing it!

When the treasurer gets chilly, I bump it to 71
So funny. Both mine are on hold at 70F...

The only difference is when the admiral gets cold I have to raise to 72f... If I let the admiral raise it it would go to 85f or so, her thinking higher temp will get house warmer faster......
 
  #180  
Old 12-27-13, 06:30 PM
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her thinking higher temp will get house warmer faster
Ya know what's funny though?

With the "BOOST" function of the ODR, it just MIGHT get the house warmer faster! If it gets pushed to 85, after ten minutes of running and not satisfying the heat call, the ODR would bump the setpoint up 10... another 10 minutes, another 10... of course by this time the house would be around 74.

But I ain't gonna tell the boss about the boost... her eyes would glaze over and she would go catatonic when she realized I was talking about boilers again anyway... but you know, some things lodge in their subconcious...
 
  #181  
Old 12-27-13, 06:36 PM
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I have to tellya something else ...

Ya know that clear plastic overlay that comes on LCD displays when you buy new stuff? Like calculators and such? A couple years ago I too a piece of that plastic and a permanent marker, and very carefully printed 72 on it and stuck it on the front of the thermostat display... all winter long it was really hard not to bust out laughing when I saw her look at the t'stat and say "Gee, it feels awful chilly in here for 72!" and then go put on a fleece...
 
  #182  
Old 12-27-13, 06:50 PM
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Troop,
For a small fee, I won't tell her. I'd be willing to wager she'd put knots on your head faster than you could rub them off. :No Beer 4U:
 
  #183  
Old 12-28-13, 09:02 AM
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I'd be willing to wager she'd put knots on your head faster than you could rub them off.
You got that right! The bald headed end of her broom and my noggin have spent considerable time together over the years!

Although, I have to say that I did eventually have to 'fess up... so she already knows! She actually laughed... and called me some words in Italian that I can't even pronounce!
 
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Old 12-28-13, 03:06 PM
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At least she only uses a broom. Mine uses a baseball bat, or at least threatens to.
 
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Old 12-29-13, 11:16 AM
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I tried the boost feature and didn't like it very much. It still takes forever to recover from a setback. I just keep it at 70 all the time. Feels way more comfortable that way too.
 
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