Boiler Installation Questions

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Old 07-31-08, 04:17 PM
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Boiler Installation Questions

Hello,

I'm about to replace a 30 year old boiler in my house with a new Munchkin 140M and am excited to find your site. I have limited experience with hydronic heating but the Munchkin installation manual is detailed and I plan to follow it to the letter. I'm hopeful someone might be able to answer some basic questions:

#1 My old system circulated a weak glycol solution. Do I need to run a cleaner through all the piping or will a good flush with water suffice? Everything I'm not replacing is copper --pipes and registers.

#2 Munchkin recommends a primary/secondary hydronic loop and I'm going to zone with 4 valves and install 2 circulators. Their piping schematic is confusing me. The return line from each zone looks like it tees into 2 places --it tees back into the line where it began and again into the suction line returning to the boiler. Page 19 of the installation manual (drawing 2a)

http://www.gasappliancesales.com/fil...nual_Rev_2.pdf

Am I misreading the drawing or is this the correct way to do it?

Many thanks for all the help.

Tom
 
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Old 07-31-08, 07:38 PM
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First, how did you arrive at 140 as the proper size? That's a honking big boiler for most residential applications.

#1. A fresh water flush should be fine. If you need to still run glycol for freeze protection, there are wye fittings, etc. that you should add to the system to make the addition of glycol simple.

#2. That link didn't open for me (pdf shows as damaged and won't open), so I'm looking at 2A here:

http://www.htproducts.com/literature/lp-61.pdf

It seems like you are misreading the diagram, but the diagram could also be better. There should be a "jump over" symbol in the returns to indicate that they do not actually tee back into the supply AND the return. They just go into the return. Same with the makeup water connection. It only ties in above the expansion tank, not into to the supply header....

Definitely pipe in the differential bypass valve at the ends of the supply and return headers.

That's a very nice installation diagram. Follow it, and the instructions for sizing the boiler loop pump, and you should be good. One mod I would make is to tie the makeup water and expansion tank into the system at the bottom of the air eliminator. Most have a tapping for just this purpose.

Make sure to have a pro tune the system, and get your local authorities to sign off on the gas piping, venting, etc. The life you save may be your own.....

And definitely revisit the need for such a large boiler. An 80 is probably plenty for a "typical" house. Maybe even a 50 if you are not doing an indirect water heater.
 
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Old 08-03-08, 09:27 PM
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Xiphias,

Thanks for the reply. Regarding the boiler size: The boiler I'm replacing is a 30 year old Slantfin 125K BTU input and 100K output. During an annual tune-up last fall an HVAC technican recommended I replace the boiler and gave me a quote on a 100K direct vent boiler --he recommended a Smith GT100. The 140 Munchkin is spec'd at 46K BTUH to 140K input. I live in a good sized house in Minnesota (approx. 2600 SQFT) where 10 below F temperatures aren't uncommon. The four heating zones in my house each run between 75 and 100 feet from the boiler to the end of the line before returning. The technican doing the tuneup last winter noted the boiler was set to run the water up to 195 degrees which he found noteworthy and thought it might be because the system was straining to keep up with demand. Do you still think I'm oversized? I'm not doing residential hot water with this boiler.

Thanks for the help.

Tom

Good advice on having a pro tune the system and of course the home inspection is a necessity.
 
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Old 08-04-08, 06:07 AM
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Originally Posted by thomas17 View Post
Do you still think I'm oversized?
Did you do a heatloss? If not you really should. You can download one from Slantfin, called Heatloss Explorer 2.
 
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Old 08-04-08, 07:13 AM
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The only way to size the boiler is to do a heatloss. As johny says, grab a free copy of the slantfin software.

www.slantfin.com

It will get you in the ballgame, and is often an overestimate of the heat loss by 15-30%. But the slantfin-ware does a "by the book" Manual J heat loss, so you're going by the book. The book just happens to have a lot of fudge factor in it.

You can get outdoor design temperatures from

http://www.crownboiler.com/educate/heatloss.asp

MINNESOTA
Bemidji -26
Duluth -16
International Falls -25
Mankato -12
Minneapolis -12
Rochester -12
St. Cloud -11


Some really crude guesses:

1) 2600 sf at -10F might have a heat loss in the 30 BTU/hr/sf range, which would be 78,000 BTU/hr, or a bit more than half of the Munchkin 140s output. So yeah, in this case, you'd be hugely oversized. IF (a huge if until you do the heat loss) that's in the ballpark, you could go with a Munchkin 80. Save yourself a ton of money on the initial cost of the unit and long-term fuel savings (the 80 has a much better modulation range than the 140).

2) If the water temp was cranked up to 195, it could also be that rather than the boiler being too small, you don't have enough radiation in the living space. What kind of heat emitters do you have? Radiators, fin-tube baseboard, other? Once you do the heat loss, you can also do a quick calculation of the heat output of the emitters using 195F supply water and see whether they are putting out enough heat to offset the heat loss in your rooms. You could have a nuke plant in your basement and the house would still be cold if you don't have enough heat emitters....
 
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Old 08-04-08, 07:37 AM
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FYI - I would be willing to bet that if in fact the water temp was set at 195*, the reason would be because of the glycol in the system. You will lose BTU's with glycol and maybe that was the tech's way of compensating for that.
 

Last edited by plumbingods; 08-04-08 at 08:18 AM.
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Old 08-04-08, 06:44 PM
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Thanks for all the help everyone; I can't tell you how much I appreciate it! Per a couple of suggestions I downloaded the Slantfin Heat Loss program and measured and input all the dimensions from my house. At an outdoor temperature of -10 my heat loss came in at just over 50K BTU/hr. Yikes! I have 2x4 framing with an abundance of 30 year old windows. Additionally I have an unheated garage beneath and adjacent to several rooms. If I do the math correctly my total BTU load is 130/hr. I guess the 140 Munchkin isn't too far off.

And the theory about the boiler being stoked up to 195 degrees because of the glycol is a good one I think. I did pull the cover off the control panel and saw the 195 setting for myself. The heat emitters are the baseboard fin type and every room in the house seems to have at least a couple of them. As an example my 21x16 living room has a total baseboard register length of 17 feet. I don't think I'm suffering from a loss of heat emitters.
 
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Old 08-04-08, 08:15 PM
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Tom, I don't understand what you mean...

At an outdoor temperature of -10 my heat loss came in at just over 50K BTU/hr. Yikes!
This part I understand I think, and the YIKES! is because it's a lot lower than you expected ?

If I do the math correctly my total BTU load is 130/hr. I guess the 140 Munchkin isn't too far off.
What math ? and what is 130/hr ? In the previous quote, you said 50K ...

Do you mean 130K ? and is that the amount of baseboard that you have installed ? If so, that has nothing to do with the size of the boiler at all. The boiler should be sized for the heat loss, and not the amount of baseboard you have.

If your loss is 50K, the 140 is way too big...

Make sure that you set all the 'factors' for the type of wall, cold partitions, etc when you run the program.

Down at the bottom of the screen, it will tell you how many feet of baseboard you need in each room ... compare that to what you have. If the program tells you that you don't have enough baseboard, that could account for the higher temp setting.

You can experiment too... change the water temp in the program around and see what you get... (hint: click on JOBS, then EDIT. Plug in your new temperatures and the program will recalculate)
 

Last edited by NJT; 08-04-08 at 08:50 PM.
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Old 08-04-08, 08:28 PM
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Me neither. 50k sounds too low, but 130k sounds a bit high. Maybe not.

And on the emitters, with baseboard it's an easy calc to do to see how the heat output compares to the heat loss. Figure 600-620 BTU/hr per foot of finned element at 195F as a ballpark.
 
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Old 08-05-08, 06:34 AM
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Hey guys,

I know his boiler is approx 30yrs old but if it still works do you think he should just bite the bullet and tighten up the house (windows, doors and insulation) first? If he installed that 140k boiler and then tightened up his house, his heatloss would drop drastically and wouldn't he just be wasting more money or is the mod-con more forgiving?

John
 
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Old 08-05-08, 07:41 AM
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Good point. In the ideal world, and also in the pre-modcon world, the preferred approach is to tighten the envelope then size the boiler to the new heat loss.

Obviously this was really important in the pre-modcon era, as there's no way to change the fixed firing rate of a traditional boiler (leaving aside that many boilers can be safely downfired up to 20% if you do it according to manufacturer instructions).

You could also size the boiler to the heat loss expected from your future envelope tightening. Now there's an incentive plan to tighten the envelope.

Of the envelope improvements, insulation and air sealing have the shortest payback (typically months to a couple years). Windows tend to be long (10-15+ years) and are often done for reasons other than heat loss (e.g., the sills are rotting out; there's water damage; part of a remodel; etc.). So in most cases, new boiler (payback 4-8 years in many situations) beats new windows in payback terms.

Modcons as you point out are more forgiving because they modulate. However, you still want the high end of the modcon to approximate the heat loss so you can take advantage of the full modulation range. Presently, most of the modcons have a 4:1 or 5:1 turndown ratio, so the lower the high end, the lower the low end.

One thing that seems to be happening with the modcons in service is that they spend basically all year on the bottom of their modulation range. "Who" could speak to this, among others. Why? Probably the generous fudge in Manual J heat loss estimates, for starters.

Whether sitting on the bottom of the modulation range is good or bad for the boiler and/or gas valves, etc. over the long term remains to be seen. But given a choice, for example, between a bottom end input of 19k (Munchkin T80) and 46k (Munchkin 140M), I'd take the T80.

FWIW, if I had to buy a Munchkin, I'd take the T80 even if my Manual J heat loss was 120k on a design day. Here's why:

1) the heat loss is probably overstated by 30%, and

2) design conditions only occur a fraction of a percent of the heating season. Sure you can get a run of super-cold weather. Maybe the boiler can't keep up. Not likely. So the space temp drops a degree or two for a couple days. Put on a sweater. Throw another log on the woodstove. Have a party with a bunch of friends (ASHRAE says ~400 BTU/hr each!). Slow-cook something on the stove for a few hours.
 
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Old 08-05-08, 08:15 AM
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Sorry for the confusing message. I won't embarass myself any further trying to explain what I was doing. When all else fails read the manual --which I did and the Slantfin heat loss program told me my total heat loss is about 64,000 BTU/hour. I am going to return the Munchkin 140M and go with an 80. Please note that I am in the process of tightening up the house. I replaced a leaky entry door last weekend and next summer have intentions of updating two ancient sliding glass doors. And obviously adding more attic insulation is a cheap and easy way to gain some efficiency. Replacing all the old windows is a decent idea but the boiler has to be first. It's like a run down old car that's nickle and diming me to excess. Three service technicians from two different firms have told me that the most cost effective solution is to replace it entirely. The burners were the latest thing to go and rather than replace them I made the decision to cut my losses. The Munchkin 80 might be slightly oversized after all the tightening but I like the flexibility it affords --a house addition one day perhaps.

I haven't had a chance to run the heat emitters through the Slantfin program but will do that soon.

Thanks again for all the help. I'll post an update in a few weeks as my project progresses.
 
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Old 08-05-08, 08:48 AM
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Good luck! If you have a choice, get the T80 (wall hung) rather than the M80 (floor/stand). The T80 has a lower bottom end. (Note however that I don't know if there's any other differences that might make the M80 preferable. I'm just looking at the brochure.)

You don't need the slantfin program to do the heat output calc.

For example, the 17 ft of baseboard in the living room, at 195F supply, gives off ~610 BTU/hr/ft. That's a total output of ~10,300 BTU/hr (17 * 610 = 10,370). How does that compare to the slantfin-computed heat loss for that room at -10F outdoors?
 
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Old 08-05-08, 10:43 AM
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Heat loss in the living room at -10 F is 9,300 BTU/hr so it looks like I'm good in that room at least. The layout in my utility room isn't friendly for a wall mounted boiler so I'm going with the floor stand.
 
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Old 08-05-08, 11:36 AM
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And the wall hung unit called The Contender, is a lot cheaper according to the sales rep. A LOT CHEAPER.
 
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Old 08-05-08, 02:51 PM
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Does your rep also carry Triangle Tube? If so, size the 60 or 110 by peak domestic usage and you're set... ideally the 60. A great boiler! They also sell a great water tank. Smart 50 minimum though - don't go small and summer cycle.
 
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Old 08-24-08, 09:36 PM
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I'm hopeful you folks will entertain another question from me; this time on circulator sizing. When I initially bought the Munchkin 140M my supplier also recommended a pair of Grundfos 26-64F circulators. When I exchanged the 140M for an 80M he said the circulator size wouldn't change. I'm trying to determine the reason behind this opinion.

My longest heat run is 90 feet of 3/4 inch copper which translates into 5.4 feet of head. (90*1.5*.4). If I interpret the graph in my Munchkin 80M installation manual correctly this means I need a flow rate of roughly 7 gallons per minute. I've been on the Grundfos website a few times and it seems there's a number of circulators that would fit within this specification.

Any advice you folks can offer would be most appreciated.

Many thanks,

Tom
 
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Old 08-25-08, 05:01 AM
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He's wrong. Show him the directions.

http://www.htproducts.com/literature/lp-185.pdf

Page 18 describes the circulator sizing. Don't pump an 80 with the 26-64. Period. The manufacturer says so. End of discussion.

Let's assume you are following one of the piping diagrams (which, IMHO, Heat Transfer Products does better than almost every other manufacturer). Like Diagram 2C. The boiler loop needs a smaller Grundfos 15-58, on speed 2.

The 26-64 is a big circulator. It has a super-high head capacity. It draws 2-3 times the power of the 15-58. Tell the supply guy you'd be happy to keep these hugely oversized pumps if he pays the electricity difference and will also pay to replace the piping when it starts to erode from too much velocity.

If you have short baseboard runs, then your space heating loops can run 15-58s on speed 1, or maybe even smaller.

Velocity in a space heating loop is typically 2-4 ft/sec, or about 3.2-6 gpm in 3/4" copper. You do not want 7 gpm in the baseboard loops. Good essay on this by Taco:

http://www.taco-hvac.com/uploads/Fil...irculators.pdf
 
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Old 08-25-08, 06:43 AM
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I appreciate the advice. I'm actually following the 2A drawing on page 22 and zoning with Honeywell valves. Would a 15-58 work both both circulators?

Thanks,

Tom
 
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Old 08-25-08, 08:36 AM
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Yup. Perfect. Make sure you install the differential pressure bypass valve as shown in the diagram.
 
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Old 08-25-08, 03:50 PM
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Originally Posted by thomas17 View Post
My longest heat run is 90 feet of 3/4 inch copper which translates into 5.4 feet of head. (90*1.5*.4). If I interpret the graph in my Munchkin 80M installation manual correctly this means I need a flow rate of roughly 7 gallons per minute.
Tom, you don't want to pump 7 GPM through 3/4" ... the max you should try to run through a 3/4" loop is about 4 GPM. Any more than that, and you will start hearing the water flowing, and Xiphias mentioned 'erosion'.

90 Feet is a bit long for a 3/4" loop. 65' is considered the max length... I wouldn't worry about it as long as the rooms on the end of that loop are historically warm enough. After that hot water travels through that loop, by the time it gets to the end, it will have dropped in temp by 20-30 degrees, reducing the heat capacity of the units it is serving.
 
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Old 08-25-08, 06:15 PM
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90 ft is long? One of my zones has about 160 ft of total straight pipe (straight pipe plus baseboard length). That plus the various fittings still gives a very reasonable total equivalent length that is no problem for a 007 or 006 at 3.x gpm.

And then of course there's the super-long zone (that should really be two) that occasioned my finding this forum back when. It's got an outrageous length of straight pipe and elbows, fittings, etc. Still no problem for a 007 to do ~3.4 gpm.

Just some points of reference. 90 ft is nice, but even in an average home, you can go quite a bit longer without a huge penalty in head or temp drop.
 
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Old 08-25-08, 11:39 PM
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Yeah ... a little ! (I'm guilty too... 88 feet here ... thankfully the end room is over-radiated and warm enough, but the bath is downstream and that gets a tad chilly)

Let's say that 4 GPM is good for 3/4" pipe.

And that 1 GPM can move 10K BTU with a 20* DT.

So, with 4 GPM, you can move 40K BTU.

Fin-tube let's say is 600 BTU/FT.

40000 / 600 = 66 FT of fin-tube.

That is of course assuming that the entire length is fin-tube, if there's a lot of connecting pipe, you could go longer and still maintain the 20* DT. Pumping the long loop isn't the problem, it's the BTUs ... there's nothing wrong with a 30* DT per se, as long as the cooler water is taken into account and extra emitters are added to the rooms on the end of the loop.
 
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Old 08-26-08, 08:00 AM
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I'm really glad to have found this forum; you guys have provided some great advice and perspective.

Another question: I discovered that the 80M Munchkin I purchased came with something called the Vision 1 system. Essentially an outdoor air temperature sensor that wires into the modulation circuit. My supplier agreed the 26-64s were too large and he replaced them with two 15-58FC circulators as the Vision 1 package requires that the circulators have integral flow checks. I'm now working off drawing 3A in the installation manual: (page 29)

http://www.htproducts.com/literature/lp-185.pdf

3A is really not much different than 2A, however, it shows a high limit safety. I'm not sure what this is. It sounds like an electrical part but looks to be mounted on or in the space heating loop. Your thoughts are appreciated.

Thanks,

Tom
 
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Old 08-26-08, 09:13 AM
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Excellent. Vision 1 is their outdoor reset and DHW priority control package. You definitely want that. The sensor is likely a simple strap-on type. Place it in contact with the pipe, wrap some pipe insulation around it, and secure (firmly but gently) with a tie-wrap or two.

Looking at the NOTICE on the upper left of p. 16, it says

"The Munchkin Boiler control module uses
temperature sensors to provide both high limit
protection and modulating temperature control.
The control module also provides low water
protection by sensing the water pressure of the
heat exchanger. Some codes/jurisdictions may
require additional external controls for high
limit and/or low water cutoff protection."

It sounds like they are using the supply sensor as both a functional control for outdoor reset purposes, and a safety high limit. This approach is a little different than, say a tekmar outdoor reset control/supply sensor, which is explicitly not a high limit safety. In the tekmar case, the high limit safety is typically the boiler aquastat.

Bottom line is that the Vision 1 will use the provided sensor as both a means to modulate the supply temperature based on outdoor reset, and as a safety high limit to shut down the boiler in the event of a malfunction.

Install as directed and you should be good to go. But I would definitely confirm this with HTP, just in case the above is a misinterpretation. You should also check with your local authority to see if another type of high limit safety (or LWCO) is required. If so, ask HTP what they would recommend.
 
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Old 09-20-08, 07:54 PM
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Final update: My new Munchkin 80M is fully operational and is working as designed. I ended up hiring a plumber experienced with Mod/Con boilers to do the bulk of the installation. The piping is tied together and organized as only an experienced hand could manage. If I could figure out how to post a picture I would but there doesn't seem to be a way without using an external link. Thanks for all the advice and perspective. I really appreciate it.

Tom
 
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Old 09-20-08, 09:24 PM
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Tom, you can set up a free account at www.photobucket.com and upload the pics there. Provide a link here for us to view... I'd like to see the pics... I'm sure others would too.

Good luck with the new system!
 
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Old 09-21-08, 04:06 PM
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Great idea. Here's a couple of pictures:

http://i443.photobucket.com/albums/q...os/boiler2.jpg

http://i443.photobucket.com/albums/q...os/boiler1.jpg

There was an interesting experience at the initial startup. The Munchkin fired right up but stumbled after a minute, tried to restart several times and then went into a lockout condition. The control board flashed an F10 error code which meant a loss of flame signal. A few touches on the key pad led us to the problem: the rectifier probe was dirty and a few light strokes from some sandpaper was all that was needed to put everything right. I'm impressed with this boiler. It is unbelieveably quiet and I'm hopeful I'll get many years of service from it.

One question: the installation manual says to check and adjust the carbon dioxide and carbon monoxide levels. The HVAC guy I hired has installed a lot of Munchkin boilers and says combustion gas analysis isn't necessary. He's coming back to load the system with glycol in a couple of weeks. Should I have him do the analysis? He does have access to the necessary equipment.

Thanks,

Tom
 
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Old 09-21-08, 05:42 PM
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Looks good ...

If the manufacturer says to do it... so shall it be done.

I'd insist.

How are you dealing with the condensate ?
 
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Old 09-21-08, 06:33 PM
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Cool. Very nice piping job. Some observations.

1) The backflow preventer needs to be piped within 6" of the floor.

2) Just to be double-sure, I suggest checking the total length of venting. That's a lot of elbows and such.

http://www.htproducts.com/literature/lp-61.pdf

On page 16 there is a table and text that describe how to do it. The allowable total of the exhaust plus intake is 85 equivalent feet.

Looking at the boiler1 photo, I see 33 equivalent feet of elbows, and about 25 feet of straight pipe. That's 58 feet. You have ~27 equivalent feet left. Where does the rest of the intake and exhaust go, what type of termination, etc.

3) absolutely, this boiler needs a combustion analysis to make sure it's in spec.

4) condensate, indeed. where's it going and is it being treated? Condensate has a pH of about 4, and will EAT any cast iron piping in your septic/sewer. It may also kill the bacteria in your septic system, if you have one.

There are simple treatment gizmos you can make out of PVC and fill with marble chips.
 
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Old 09-21-08, 09:45 PM
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The venting goes through an outside wall just a few feet out of the picture --total equivalent length is well short of 85 feet. The exhaust terminates to the screened T fitting that came with the boiler. The intake has a 90 degree elbow on it.

That's a good point on condensate. My installer soldered up a copper line and tied it into the boiler's condensate trap but he switched to a plastic hose when I showed him the section in the manual that warned about pH. I didn't think about the affect on cast iron. The hose dumps into a floor drain and cast iron carries whatever all the way to the sewer. I'll build that gizmo you suggest. Where does a guy get marble chips?

I'll also pipe a line from the backflow preventor to 6 inches off the floor. You confirmed my thoughts on the combustion gas analysis. My installer told me that a Mod/Con boiler starts modulating it's gas flow immediately after it fires up --thus defying any accurate combusion gas testing. In looking through the manual I see a requirement to put the boiler in test mode when doing the testing. I'll have him do it.

Thanks again.

Tom
 

Last edited by thomas17; 09-21-08 at 09:46 PM. Reason: typo
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Old 09-22-08, 05:48 AM
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Marble chips can be had at a garden center, or a big-box store. Bigger chips are better than pellet-sized or gravel. The small sizes turn to mush.

I've got a simple neutralizer design around somewhere. Will post a link to photobucket image when/if it's found.

Have read stories about floor drains and associated cast iron piping being eaten in a matter of months. It's important.
 
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Old 09-22-08, 02:39 PM
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Now that I have this fancy Mod/Con boiler I find myself motivated to upgrade the four thermostats that drive it --once my bank account stabilizes a bit that is. I'd really like to control and program all four zones from a single panel. I'd also like the ability to check and control the system remotely via a standard phone line or internet browser. I spent some time recently searching this forum and other places for ideas but I haven't found anything that meets my needs. Does anyone have a recommendation?

My house is wired up pretty well. I have easy access to standard phone lines. I have a high speed cable internet connection and have CAT5 running in spots. I also have a high-end wireless router although I'd be reluctant to run the heating control wirelessly as it would seem to be a reliability concern.
 
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Old 09-22-08, 03:04 PM
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Here ya go. Knock yourself out.

http://tekmarcontrols.com/literature...at/p315web.pdf
 

Last edited by xiphias; 09-22-08 at 03:36 PM.
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Old 09-22-08, 03:32 PM
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Couldn't find the pic of the condensate neutralizer. Here's a description. It will be a lot cheaper than wiring your boiler and house up with tN4....

Everything PVC.

Two 3"x1" tees (that's 3" dia PVC pipe with a 1" tee coming off it)
One 3" end cap.
One 3" rubber cap

scrap 3" PVC pipe. Need about 8-10" total.

glue the tees together with a piece of scrap. It qualifies as "fancy" if you make the side tees oppose or at 90 degrees.

glue end cap on bottom with a piece of scrap. (this thing generally stands vertically -- will have to be strapped into place or otherwise provided a stable base. Nice if it is easily removed for cleaning/service.) The outlet should be lower than the condensate drain on the boiler. You can also lay the thing flat but you should probably use a waste plug instead of the rubber cap in that case.

get appropriate reducer/coupling to run your condensate hose into the bottom.

get appropriate tubing or reducer/coupling to run the output (at top) from the neutralizer to the floor drain.

fill with marble chips to the top of the outlet.

place rubber cap on top. friction fit.

Periodically inspect and replace chips. Watch out for sludge build up, and hose the thing out if so.

Consider finding a cheap pH test kit to see what the pH is going in, and coming out. Probably around 4 in, 7-8 out.
 
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Old 09-22-08, 09:00 PM
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Xiphias,

I noodled on possible designs for a condensate filter this morning and then picked up a few fittings on my way home from work tonight. Here's what I came up with:

http://i443.photobucket.com/albums/q...eutralizer.jpg

It's a little different than your the concept you posted this afternoon but still a workable solutioin I think. It's made of 2 inch PVC, necking down to inch and half and then to half inch pipe thread. I put a threaded joint in the middle so I can take it apart. I have enough marble chips to last the life of the boiler and then some.
 
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Old 09-22-08, 09:25 PM
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Tom, what are the pads the equipment is sitting on ?

Do test the PH to make sure the neutralizer is doing what it should.

Does there need to be 'contact time' in order for the marble to do it's job ? Tom's design looks like the condensate could run straight through, rather than bathing the chips for a period of time.
 
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Old 09-23-08, 04:57 AM
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Troop, those pads are thin concrete slabs. Around here used outdoors for siting A/C units, things like that. Great idea for boilers and water heaters!

Tom, time will tell if that setup works adequately. Get a test kit and check it periodically. Trooper is right about the need for some 'contact time' but I don't know how one would figure out how much contact time is needed. Your system may condense a lot (gallons/day) or a little, depending on how it runs, what the water temps are, etc. etc. So flow rate might be a trickle/day or something more. Is that enough contact time? I dunno.

I don't mean to make you paranoid, but you absolutely need to keep an eye on this and make sure what comes out is not corrosive. Cast iron floor drains and piping are exactly the thing that one reads about failing due to untreated condensate. It would obviously be a 'big deal' if you had to cut out a bunch of rotten cast iron piping under the floor....
 
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Old 09-23-08, 11:09 AM
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I'll keep an eye on it and get one of the test kits per your recommendation. Incidentally, Munchkin makes a similar device:

http://www.2hsc.com/pdfs/munchkin/co...eutralizer.pdf

I set the boiler and water heater on big concrete patio blocks picked up from a local home center. I wanted to get the boiler and water heater off the floor and was hoping to find something to close to what my outdoor AC compressor sits on but after several calls to HVAC contractors and suppliers I came up dry --all I could find was plastic. I didn't like the idea of a boiler/water heater sitting on plastic so I went with the patio block.
 
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Old 10-04-08, 09:55 PM
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Where is the zone valve?

I like the pictures you posted. I am in the middle of an installation myself. Looking at your picture, I can't quiet make it out. Where is the zone valves connected to? On the supply header or the return header? All the installation schematics I have reffered to suugests installing the zone valve on the supply side. However, the Honeywell zone valve install manual suggests installation on the return side. Does it really matter?

GV
 
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