Help with Lochinvar Efficiency+ 300 MBH

Dave_61

We have a Lochinvar Efficiency+ 300 MBH boiler installed since our house was built 4 years ago.
The installer at the time had never installed one before, and we have had problems with noise and short cycling.
The boiler is an EBN 300.
We have approx 6000 sf of living space.
This is heated with 3 separate hydro air units, Phase III TR-60 indirect unit, and a radiant loop under master bath floor (about 20x20 space).
If we have someone come out and repipe this thing in the correct primary/secondary configuration, will we get rid of these problems?
The Lochinvar rep that came out last week recommended replacing our 4 year old boiler with two 150,000 MBH units.
The other option was a buffer tank because he says the main boiler circuit has so little water (about 5 gallons) that that is the reason it is short-cycling. However, he quoted us a price of $3000 for a buffer tank.
From this site, I have seen that people are using hot water heaters. Would I really need a 200 gallon tank, as Lochinvar specifies for my boiler?
Our main circuit is 2" pipe (as the original installer said it was needed to prevent the noise from low flow), and we have glycol in the system. Is 2" overkill? I haven't seen any hot water heaters with 2" connections.
Our problem is that no one around here has much experience with these boilers, and they all scratch their heads when looking at it.
I have didgtal pictures of the primary piping setup if that would help.
Thanks so much.
Dave

hr

A very common problem

when boilers are oversized. Compounded by the low mass low water content of that boiler. Copper tube boilers heat up very quickly, if you do not have the load they will cycle as you indicate.

The buffer is one option, a properly sized condensing modulating boiler would be anothe. possibly you could trade out the current one towards the price of a modulating condensor.

You can size that buffer exactly to your job with the HDS software available at www.hydronicpros.com

Sounds like your installer could use a copy

This shows a 240,000 output boiler with a 100 gallon tank. 140-180 delta t, one 50,000 zone calling. Gives you a minimun, in my opinion, 10 minute burner cycle.

hot rod

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Dave_61

what do you think?

The options I have are to put in a buffer tank or to change out to a Weil-McLain modulating boiler, which I know by the supplier is about $4000.
I guess I could get a 150 gallon tank, but I want to make sure this is what I should be doing, as opposed to spending the big bucks on a new boiler. The Lochinvar rep will help me with the purchase of new Lochinvar products only.
My original installer insists there is nothing wrong with the short cycling and says the boiler is designed to do that.
Is it possible to buy a 150 gallon tank/water heater to use as a buffer tank? What would be a brand I should look for and ballpark price?
Thanks.
Dave

hr

Personally

I think the cost to replace the boiler or add a large enough buffer PROPERLY installed would be a wash possibly.

Quite a bit of potential piping to get the buffer installed so that the boiler is still protected from long cold periods, that the loads pull from the buffer without flow through the unfired boiler, etc, etc.

So the 4K for a new possibly simple boiler change out, balanced against a major repipe??? If it were me I'd like the new more efficient heat source.

That Loch would make a great snowmelt or large DHW with indirect. Got to be a buyer out there for a used 300.

Price both options, but, be sure the buffer is installed correctly. You could make the current install worse.

Time the short cycle length. Send the data to Lochinvar and see if they are comfortable with the run cycles as documanted.

Regardless of the installers opinion, short cycling presents a lot of wear on all the electro- mechanical components of that boiler. Lots of expensive parts under the hood of that unit.

Usually fuel efficiency is in the toilet with multiple short cycles like that. How's yours?

You would be well advised to get a good hydronic designer to draw up a good, workable buffer drawing

Good luck.

hot rod

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hr

An excellent

seminar was presented on this topic a few years back. You might contact Siggy at www.hydronicpros.com for some info. He is very generous with his material. Possibly hire him to draw up the best approch, then bid it out.

A heatloss calc would be nice to get all your ducks in a row before you start chopping

hot rod

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GREG LAUER

BUFFER TANK

EVEN IF YOU INSTALL A NEW BOILER YOU NEED TO LOOK AT THE WHOLE SYSTEM.IF THE RADIANT LOOP FOR THE BATHROOM IS A SEPERATE CIRCUIT AND IT IS THE ONLY ZONE CALLING YOU WILL STILL SHORT CYCLE YOUR NEW PROPERLY SIZED BOILER.INSTALLING A BUFFER TANK WILL ELIMINATE THIS PROBLEM.

GREG LAUER

QUESTION

WHY WAS GLYCOL INSTALLED?

Dave_61

Glycol was installed because 2 of the air handlers are in unheated spaces (in attic).
I was told by someone that if we replaced the individual pumps to the air handlers with zone valves and left the valves open all the time, it would alleviate all the problems with short cycling and noise as water would circulate constantly in the coils thus increasing the amount of water cycling even when just the radiant is calling.
Does this make sense?
I am including a picture of my setup to just give an idea of what we have. What follows is a short explanation of the picture....
You can see the main boiler loop which is 2" cast iron with the pump in the loop. There are 5 zones (3 air handlers, the indirect water heater, and the radiant floor).
This first picture is a general overview of the setup.The supply pipe is that first vertical 1 1/2" pipe just to the right of the pipe hanger in the center of the picture. It goes up to supply all the secondary pumps to the different zones. Then you can see all the returns coming back down with the hose bibs and attaching to the primary boiler circuit just past the supply pipe (to the right of the shiny metal BX cable). Both the supply and return pipes are dead-ended, as you can see the automatic air bleeder on the end of the return pipe (just to the right of the logo that says "Phase III"). Also, note the position of the bypass in the picture. The 2" pipe in the primary loop tends to zig-zag back and forth on itself.

Dave_61

picture

GREG LAUER

need more

please post a better picture of how pumps are piped i see alot of problems and i dont see a true primary secondary system yet.

Dave_61

re: need more

I will post some more pictures tonight when I get home.
Which pumps are you referring to? The smaller zone pumps?

GREG LAUER

yes the zone pumps really any pictures that show better overall view of system

Dave_61

closeup of main boiler pump

Here is a closeup of the boiler primary pump where you can also see the tees for the supply manifold (with vertical 1.5" pipe) and return manifold right next to it. Note that the tees for the manifolds are connected together in the picture, although each amnifold is dead-ended in the first picture.
I will send more pictures of zone pumps this evening.
Thanks.
Dave

Dave_61

picture of pumps

Here is a picture of the zone pumps on the supply manifold.
The manifold is a dead end with an automatic air vent on the end, which can be seen at the upper left of the picture under the foil buctwork.
The return manifold is also a dead end with an air vent on the end (which can be seen in the middle of the picture next to the green relay box).
Both the supply manifold and return manifold come off the primary 2" boiler loop via tees that are right next to each other on the boiler loop. The tees are thus connected together. This can be seen in the second picture (the supply manifold is the black vertical pipe just to the left of the BX cable, and the return manifold where it enters the boiler loop is the 90 degree elbow just to the right of the BX cable). Note that these tees are connected together into the main loop.
Email me or post if you have any other questions.
Thanks again.
Dave

GREG LAUER

check ohttp://www.pmmag.com/CDA/ArticleInformation/features/BNP__Features__Item/0,2379,21599,00.htmlut this explains alittle about p/s/piping and common mistakes
first glance 90's right out of pumps is bad and causes noise.way to many 90's used. primary loop looks like a theme park roller coaster.you have a secondary on top of a seconday not really sure about that never saw it tried before.i cant belive a lockinvar rep looked at this and couldn't see problems.ill look at it harder later and see what else is wrong. why did they use black pipe?

Dave_61

they used black pipe...

They used black pipe becuase the original plumber said that copper was causing noise becaue it was restricting flow. Now it seems like the head loss is so low with the black pipe we are having problems with the 0012 pump burning out.
What are you referring to when you mention 90's? Are these the flow checks?
I have a new plumber coming who is familiar with these Lochinvars and will just pay him to repipe properly.
Should I try to recoup my costs from original heating contractor/ He says the piping is fine the way it is.

GREG LAUER

primary pump has elbows on either side to close to pump and with out checking flow specs a o12 is probable over kill hopefully the new plumber knows more about p/s than the last i dont think repair is going to be to bad and for those who have said boiler was oversized don't forget glycol reduces compacity.look at the artical i mentioned or search primary secondary piping and you should see the extra loop i'm refering to you don't need it and you can probable go down a size or two on the pumps good luck with the new plumber.

Dave_61

Thanks

Thanks, Greg.
The new plumber seems to know what he's talking about, at least per our phone conversation.
What do you think about the primary piping....The boiler is 300 MBH. The 2 air handlers for the first and second floor EACH are 88 MBH. The air handler for the 3rd floor is 60 MBH. Plus we also have the 60 gallon indirect and the small radiant loop.
Wha do you think regarding pipe diameters for the primary loop as well as material. Should we stick with black pipe or go to copper? All the other smaller loops are 3/4" copper except the indirect water heater which is 1 1/4" copper.
The specs for the boiler require minimum 15 gpm flow through boiler (should really be about 25 gpm).

Dave Stroman

It is amazing to me how many "reps" can look at the piping on their boilers and "see no problems". Anyone who knows primary/secondary pumping can see that this boiler is not set up correctly. The big taco pump looks like a 0013 or 0014. That is more that enough for that boiler. The fact that there is a bypass in there shows me that the guy just did not get it. I do not think it matters if the piping is black or copper. Copper will be easier if you are going to redo it. Some of the noise may be coming from the fact that the flow of the boiler pump is added to the flow of the zone pumps. One of the key things of p/s pumping is that the pump should not induce flow in any loop other than it's own. If the boiler pump flows at 25 gpm, then it should never change regardless of how many zones pumps are runing. And the flow to the zones should never change regardless of wheather the boiler pump is running or not.

Dave in Denver

Dave_61

IN p/s does total flow become an issue?

In a true primary/secondary system, say the primary pump is circulating at 25 gpm, which is right within specs for my boiler.
Does it matter if the total flow of the secondary pumps exceeds that? (say they all (5) came on at the same time and the total flow from all of them was more than 25 gpm). Would that cause a problem?

Dave Stroman

The issue is not so much that you can over pump the boiler. The issue is that the way it is piped, the boiler pump can induce flow in the zone loops and the bypass is piped as a boiler bypass, not as a system bypass. What that means is when you open the bypass valve, some of the flow of water byassses the boiler which is exactly not what you want to do with a copper boiler. Close the bypass and some of the noise and short cycling may go away. Yes, a buffer tank might help but this system can be made to work just by piping it correctly. I have one job where I used an outdoor sensor to keep the high fire of this boiler from not even operating until the outdoor temp was below 35 degrees. Make that 1st stage work as much as possible before the high fire comes on. And make sure the high fire aquastat is set at least 30 to 40 degrees above the low fire. These aquastats are not the most acurate. Use the temp. gauge to get them dialed in.

Dave in Denver

Dave_61

Had a furnace guy come out and look at it today...

He recommends getting rid of the boiler and putting in a new one as he is not comfortable with Lochinvar.
He is going to give us a price for repiping and also for a new system.
What do you think, Dave? The noise happens whenever the boiler comes up above 160-170 degrees and really started when the antifreeze was added. We used to have this brown stuff (i believe it was called Herchem) and the new stuff is called NoBurst. I spoke with someone from Noble who makes NoBurst, and he said they have had problems with noise in copper heat exchangers with scale.
I just don't want to put a ton of money into repiping and find out we still have the noise issue.
Thanks again.
Dave

GREG LAUER

bottom line

bottom line your noise trouble are from bad piping design and probably some over sizing of pumps. I also see no insulation PLEASE find youself a MECHANICAL contractor that is willing to fix other peoples problems humbly. a new boiler won't help you. also please add a buffer tank to your primary loop. your entire system needs evaluated and though you can get some great imput here we arent there so many things could be missed. wish you luck and if anyone knows a honest contractor in this guys area hook him up

Dave_61

Thanks Greg

Thanks Greg. I live in the Hartford, CT area. If you guys know of anyone who would be able to help me, I'd really appreciate it. The problem is that most people do not want to touch someone else's mess, and they'd rather rip it all out and start new in order to give a guarantee.

Dave Stroman

Can you discribe the noise?

Dave in Denver

Dave_61

noise

Most of the time, it makes a kind of rumbling sound as the water/glycol starts to heat up, but as it gets to operating temp (180), sometimes you hear a shrieking/chattering.
I spoke with a tech from the Noble Company who makes the NoBurst antifreeze, and he said it may be from foaming.
When I opened the tap on the boiler, a fair amount of foam came out.
Could this be the cause of the noise? Since we hadn't had it before this type of glycol was put in.

Dave Stroman

You are never going to handle this problem until the piping get redone. Perhaps there is something I can not see from the photo, but the problem you discribe is a flow problem. The bypass is in the wrong place and is not even needed in a true p/s pump system. Antifreeze in the system changes the flow rates. There is simply not enough flow through the boiler. It is not a boiler problem, it is not a boiler, it is not a boiler problem. I can not say it enough.

Dave in Denver

GREG LAUER

opportunity

hey,dave (in denver)looks like the service market is ripe for the picking in conn.i would just feel bad selling every customer that got a bad install a new system!sounds like conjob 101 is taught before basics of hydronics.how sad

Dave Stroman

You know, there is nothing really wrong with his boiler. The installer just did not understand p/s pumping. And with the bypass valve open it robs even more of the flow to the boiler. He needs to close that valve to start with. (I hope he is listening) P/s pumping has been around for so long now that it is amazing that installers are not catching on. Just like pumping away. I had to explain to a friend of mine the other day, who is a plumbing and heating contractor, and was putting a new boiler in his own house, what pumping away was. I asked him how often he had to purge his old boiler. He said every couple of months. Well..... what can we do but keep trying to put the word out there.

Dave in Denver

Dave_61

Well, it's definitely going to be repiped

Well, it's definitely going to be repiped. I seem to have found a plumber who knows P/S piping. Now what should I do about the original contractor? He had a new plumber that he was paying come in and check out the system (I had refused to have the original plumber come back).
The "new" plumber came in and added the useless bypass. Now the heating contractor says that the way my system is piped is the way they pipe all of their high efficiency units, and they have had no other problems.
Do I save myself the aggravation and just pay someone to do a complete repiping, or do I somehow prove to this heating contractor that my system is piped wrong, and how would I do this?
Thanks again.
Dave

Dave_61

Well, it's definitely going to be repiped

Well, it's definitely going to be repiped. I seem to have found a plumber who knows P/S piping. Now what should I do about the original contractor? He had a new plumber that he was paying come in and check out the system (I had refused to have the original plumber come back).
The "new" plumber came in and added the useless bypass. Now the heating contractor says that the way my system is piped is the way they pipe all of their high efficiency units, and they have had no other problems.
Do I save myself the aggravation and just pay someone to do a complete repiping, or do I somehow prove to this heating contractor that my system is piped wrong, and how would I do this?
Thanks again.
Dave

Dave_61

Well, it's definitely going to be repiped

Well, it's definitely going to be repiped. I seem to have found a plumber who knows P/S piping. Now what should I do about the original contractor? He had a new plumber that he was paying come in and check out the system (I had refused to have the original plumber come back).
The "new" plumber came in and added the useless bypass. Now the heating contractor says that the way my system is piped is the way they pipe all of their high efficiency units, and they have had no other problems.
Do I save myself the aggravation and just pay someone to do a complete repiping, or do I somehow prove to this heating contractor that my system is piped wrong, and how would I do this?
Thanks again.
Dave

Dave_61

Well, it's definitely going to be repiped

Well, it's definitely going to be repiped. I seem to have found a plumber who knows P/S piping. Now what should I do about the original contractor? He had a new plumber that he was paying come in and check out the system (I had refused to have the original plumber come back).
The "new" plumber came in and added the useless bypass. Now the heating contractor says that the way my system is piped is the way they pipe all of their high efficiency units, and they have had no other problems.
Do I save myself the aggravation and just pay someone to do a complete repiping, or do I somehow prove to this heating contractor that my system is piped wrong, and how would I do this?
Thanks again.
Dave

Dave Stroman

I guess it depends on how much the cost is and whether it is worth the brain damage to go after him. Perhaps an exact drawing of the piping can be made along with photos. Then a drawing of the piping after it is redone, with photos. Wonder if a judge would ever know the difference. You may need expert witnesses. Or better yet, talk to the contractor and negotiate. If you can get it piped correctly and working good, then you have some leverage. Makes you wonder how his other systems are working. Hot water systems are so forgiving and I have seen them work sometimes when you'd think they should not. Unfortunately, yours was one of the unforgiven.

Dave in Denver

Dave_61

Is there anyone who can design me a schematic that I can give to

a new plumber?
With my Lochinvar Efficiency+ EBN 300 model boiler and the problems we have had with noise and shortcycling.
A rep from Lochinvar came to my house a couple weeks ago and recommended replacing the current 300 MBH boiler with 2 smaller units. I do not believe that that is the answer to our problem.The Lochinvar tech people seem to be very uninterested in giving me a specific diagram.
I have had a couple plumbers come to my house, and they understand the whole primary/secondary concept, but they are very wary about actually repiping the boiler without a schematic, as NO ONE around here seems to be familiar with Lochinvar, and they say they can't guarantee the problems would stop.
I have downloaded the primary/secondary piping diagrams from the Lochinvar website, but they do not seem to be as detailed as these plumbers would like to see.
I would pay someone to design me a piping diagram from the ground up. I could give them the specifics of my system and get a schematic showing each pump, valve, and connection for each zone along with piping materials and sizes.
Just for a little background....
There are 5 zones as follows:
Zone 1: Hydroair coil rated at about 88,000 BTU
Zone 2: Hydroair coil rated at about 88,000 BTU
Zone 3: Hydroair coil rated at about 60,000 BTU
Zone 4: Indirect Hot Water Heater (Phase III brand) TR-60 (60 gallons)
Zone 5: Radiant loop for master bathroom floor that is approximately 300 square feet of floor space.

All pumps are Taco 007's. If someone could come up with a diagram with the primary boiler loop with the correct diameter tubing and tubing type as well as correct sized pump, as well as where the connections should be for each secondary loop and how each should be connected, I would be so grateful.
My only other option at this point seems to be to get rid of the boiler and replace it with a standard cast iron unit that these guys feel comfortable piping.
I called John Siegenthaler, but he is away for awhile. Would he be the best person to discuss this with?

Thank you.
Dave Freitas
Please email me with any other questions or comments you may have.

Dave Stroman

I can help you with a basic drawing. But you and your plumber need to know that the piping on this boiler is not any different then any copper tube boiler. There is nothing magic or unusual about Lochinvar. Because it is a 300,000 Btu boiler, flow is more important. The other thing nice about this boiler is that it is 2 stage. It is almost like having 2 boilers in 1. Changing to 2 copper boilers will not make it any less complicated. And once you get the primary boiler loop set up, it is not any more complicated then any cast iron boiler. It is the nature of copper boilers to short cycle under light loads. There is a few things you can do to minimize this.

Why don't you contact me off the wall and I will see if we can get you pointed in the right direction.

davestroman@hotmail.com

Dave in Denver

Dave_61

Thanks Dave

Thanks Dave,
I truly appreciate it.
Dave Freitas