Four questions for Munchkin install

Mike T., Swampeast MO

Of course I don't deny, but it's not years--it's decades.

You know what though? Gone are the days when it was acceptable to waste even 10% of your <I>seasonal</I> energy up the flue. The finest boilers require combustion analysis only for verification upon installation.

Please explain your perspective.

Robert_22

Four questions for Munchkin install

Wall:
I learned a lot by reading through the material presented to me at this site, when I asked questions a couple of weeks ago. I have 4 more questions.

1) Why do we need the pumps to pump away from the expansion tank
2) What is involved in balancing the system? (i.e., How is it done.)
3) What are the basic principles behind properly setting the curves.
4) What are the basic principle behind performing the combustion analysis

Appreciate your responses and pointers to url reading material.

Thanks,
and Happy New Year,
Robert

Southside

Starting with number 4 a UEI manual has a little bit on combustion:

http://www.ueitest.com/images/Product Manuals/C50-C75 Web Manual.pdf

I ask about combustion trim in a previous post and got little useful info. Someone did throw out the standard line about only trained "professionals" should adjust a gas valve. I guess maybe they don't get their shoes wet when they cross a river or something but there are only two valves to adjust. It's not rocket surgery or brain science. As near as I can tell they are just attempting to protect their earnings since safety is not an issue for any half-way competent (read: someone who can install their own boiler) individual.

Moving to number one, there seems to be some reference to Don or Dan or someone as some sort of authority who sez pumping away is good. From a practical stand point a pump increases pressure or head so you want a pump to add pressure or head from a constant pressure point. The other side of that is that you really don't want to force a pump to suck. Pumps have ratings called net positive suction head and that is all they can handle for drawing fluid. It's much better to have a pump pushing fluid around rather than trying to force it to suck fluid around. In other words can you spit water further than you can suck it up a straw? Of course you can.

Well that's enough stirring the pot for now. Let the flames begin...

hot_rod

tough questions

to answer without seeing your system.

You don't have to pump away from the expansion tank, but generally it works better for air elimination and provides the best working condition for the circ(s)

Did you pipe P/S or with any type of hydro separator? Pump into the boiler is the best method for high pressure drop HX boilers. All the installation manuals show the boiler circ pumping into the boiler.

By balance do you mean flow through the boiler, or the various loops of a radiant system? If you have a radiant system with un-equal lopps, then a flow meter on every loop is one method to balance. temperature delta t is another, or use your hand to balance by feel.

As for primary loop flows or flow through hydro separators, there are formulas to determine the flow rates under various conditions.

The Bacharach site has some excellent info on combustion anaylsis. It is a fairly complex subject takes some practice and experience with an analyzer to understand how to adjust correctly. Your question, on this subject is a lot like asking someone how to fly a plane

Proper flow through the boiler AND proper flame adjustment are critical to that appliance, that is why many of the tradespeople her suggest you get a trained pro to help, it's not that a HO can't do it, but without training....

I'd guess 90% of the problems that come by here with high efficiency boilers such as lockouts, excessive fuel usage, moaning or other noises, vent freeze up, etc, have to do with installation and setup mistakes.

Just some thoughts without knowing your skill level of course.

hot rod

Robert_22

I posted pictures on this site a couple of weeks ago, because my installer didn't follow the munchkin manual. One of the people that rsponded indicated that my system has 4 pumps and only 2 flow control valves. (My pumps are not IFCs either.) The responder said that when it gets cold and my system starts kicking it up, I will have wild flow isues and my domstic water will get very hot. He also asked whether the installer balanced the system. I'd like someone to spread a little more light on this for me. I'd like to point out to you readers on the Wall that when the temp got cold (i.e. 8 -20 degrees), my family noticed that the domestic water (indirect superstor) did get very hot. When it got to the 8 degree level, our water was scolding hot, so the guy Wall Reader was correct. Our house is not comfortable either. We have to keep our thermostats at 74, yet it doesn't warm up uniformly. What is going on with my system? One last question: are the flow control valves used to balance the system?

I need information, so I can get smart just enough to convince him to correct his deficiencies.
-Robert

Mike T., Swampeast MO

Oh! It's that system...

All I can say is that the installer was utterly clueless with regards to converted gravity systems and beyond that I doubt that he ever read--much less studied--the instructions that came with the boiler.

If you have a decent relationship, have him come back to make corrections at HIS learning expense. Both of you will benefit from the experience.

Mark Hunt_3

I remember your system


The flow checks I spoke of are required whenever you have multiple circulators. They prevent flow in any zone that is not running.

Your domestic tank is getting flow through it even when the tank temperature is satisfied and the circulator for that zone is not running. This is what is causing the water to get scalding hot.

Without the flow checks, you would also be pulling water through the heating zones that are not calling. That can cause issues with balancing the distribution of heat throughout the house. There is no control over where the water/heat goes.

HTP also clearly states in their instructions that the burner must be checked with digital combustion testing equipment. It is the only way to assure proper and most importantly SAFE combustion.

Combustion testing IS rocket science in a sense. NASA engineers don't just fill the space shuttle with gas and let her rip. If you do not understand the how and why of combustion, you will not know what the readings from a combustion analyzer mean. If you don't understand the combustion numbers, you will not know if the unit is firing correctly.

Ask your contractor to pipe the boiler according to the instructions. Ask him to install flow checks on all the zones. Ask him if he can perform a combustion analysis. That is something he may not be able to do. Sadly, there are many contractors that still do not own digital combustion testing equipment. Some who do, do not know how to use them. You may have to find someone else to do the testing.

Hope this helps.

Mark H

Southside

Mark, combustion is far from rocket science. For years we all adjusted the combustion based on gas flow and flame color. Don't get confused just because we have sensors now that let us put numbers on the description.

Mike T., Swampeast MO

May I ask how you adjust "by eye" in a sealed combustion chamber where the flame in not visible?

And yes! when a properly adjusted fuel/air mix can result in sustained flue temps below supply temp it IS freaking rocket science!

Mark Hunt_3

I'm not confused


and I am not going to argue with you.

For years people thought the earth was flat too.

We know better now.

Mark H

Southside

Sure you can ask. I'll ask that you keep things in perspective. For years we had open combustion and didn't do much more than check flow and color. Do you deny that?

Sealed combustion is different but it is far from a situation where we can only rely on a few remote observations and an inability to stop the operation.

Keep it in perspective.

Southside

If you are comparing combustion analysis to prehistoric and early historic astronomical observation and belief systems then you are confused - severely.

Do try to keep it all in perspective...

Southside

MAQ Crook

Munchkin Don't buy headache

When it comes to a munchkin Don't buy as I have been hassling with them for 2 plus years and their support is even worse as they would not get back to me. They did finally take back the unit only on the distributers demand but they would not sell me an alternative. I had to tear the system apart three times and still it did not work right. It would have paid 3 times over to have another system put in by someone else.

tom_49

Maqcrook,

Most times these boilers get bad mouthed is because of poor installations. We re-pipe these all too often,because the original installer had no clue. Are you the installer or HO? Why did you have to "tear it apart"?

I have installed about 25 of these ( exactly as per man. specs. ) and have had VERY few problems. HTP support in great. Sure, they may get busy this time of year, and you can have trouble getting through,but they always get back to you. Sadly, I think their tech. lines are tied up talking to guys that cant read the instuctions (or follow the drawings), or care to learn.

tom_49

Another Know-it-all.

People come here for help w/their systems and to learn.

When you stop listening, you stop learning.

Happy New Year.

Tom

hot_rod

I used to tune my truck my turning

the distributor till the engine would ping, then back it off a tad bit. Try tuning a new truck by ear these days. You may not even have a distributer to turn.

I agree the proper analyzer and the knowledge to read and interpet is a must with modern high efficiency equipment.

Tune by "eye" and you may get a lot of F09 callbacks

hot rod

GW

wow

either all of the best heating pros who know their elbow from their eye socket started drinking a bit too early, or some non heating pro took a few too many smart pills.

Pumping away... what in the world does that have to do with a Munchkin install? Most pros who know better keep the system(s) on their own pump(s), and the boiler on its own pump. Oh yeah, it's in the manual too.

Please don’t touch the gas valve without a combustion analyzer!

If Jim Davis catches wind of this, you're toast!!

Happy New Year to all,

Gary




To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Southside

Well Mike it's easy. I referred to a common practice and you went to an extreme. Your example was out of context and accusative. It still is. When you settle down a bit and accept facts perhaps you'll understand that the perspective is that combustion trim is a simple matter of flow and mixture.

Southside

I don't claim to know it all Tommy but I can keep things in perspective. Combustion trim is nowhere near rocket science. It's a fairly simple matter of mixture and flow rates. A few controlled observations it's fairly easy to get the desired results.

[Deleted User]

I beg to differ...

and I am qualified to differ.

I have been trained and certified to test, adjust and correct improperly fired gas appliances. You, I do not know who you are or what your credentials are, but you are spouting mistruths. Although it may not be ROCKET science, it is nonetheless a science. If you feel good about eyeballing burner set ups, so be it. When you have a wrongful death lawsuit staring you in the face, you will wish you hadn't depended upon your simple eye. Trust me. It can not be done, and you shouldn't be saying so.

If you and I end up in court against each other over a carbon monoxide case, you will lose.

Quit trying to make it sound so insignificant and simple to do. One wrong turn of a screw driver can and will kill people. Especially in the hands of an untrained, unskilled person spouting mis-truths.

You are picking flack in all the wrong places. Be smart and stop it before someone gets hurt.

Mark Eatherton

tom_49

OK, maybe not rocket science, but if someone living in a building that you "eyeballed" the flame gets injured. You are dead if you have to go to court.

I was on a job recently where 3 other guys couldnt figure out why the CO detectors in the house were going off (fire dept. included). I walk in with my comb. analyser, stick it in the flue, 2500+ppm in the flue. You cant detect this "by eye". This unit was a gas FHA, Im not even gonna get into trying to "eyeball" oil . I'm not tooting my own horn, its just scares me the amount of people running around fixing heaters that dont ever re-educate or try to learn better practices on things.

I bought my analyser ( 3 yrs ago)after reading countless posts here on the subject, Ive been to Jim Davis' class which I strongly recommend to anyone who wants to know about CA and keeping their customers safe. Gotta cover your butt these days.

Steve Ebels_3

If you don't test...........

You don't know, indeed, you can't know.

In older equipment, oil and/or gas, you could make it run "by eye". Was it always the best it could be? ....... See the opening statement.

It worked because of factors like lower efficiency, wide flue ways, gobs of excess air, drafty houses, and chimney's that will suck like a Hoover. In modern equipment that modulates the air fuel mix is much more critical with very little, if any margin for error. Now add condensation to the mix and ANY residue from less than perfect combustion becomes a severe heat exchanger blockage.

The simple fact is that the new high efficiency equipment is definitely not adjustable "by eye". Many times there isn't even an inspection port to observe the flame. So how could you adjust it visually? How does one check the CO content of the flue gas by seeing the flame?

Inquiring minds want to know and I'm always looking for new and better ways to do things. If you can tell me how to correctly set up a burner in a Munchkin/Viessmann/Weil McClain or whatever, without an analyzer I will gladly forgo the expense of buying an analyzer and maintaining it. It would be an extra $2K in my pocket.

Southside

Mark - chill out and read my posts. At no time did I advocate setting up a burner without analysis. Can you admit that?

What I did say is that combustion analysis is no big deal. Obviously one has to pay attention to what they are doing and not leave a system producing CO outside of specs.

Based on your reading and comprehension skills I do have to ask if you can pay attention. Can you?