Hydro Seperators

MikeyB

Is it advisable to install a Hydraulic Separator (LLH) on a small Mod-Con such as  Knight wall hung WB-080 or a Munchkin T80, any advice is much appreciated, thanks guys

Robert O'Brien

It's

either that or P/S, so take your pick.The LLH is easier to make look good and some other benefits.

CMadatMe

Low Loss Header

How have you been Bob. Hope all is well. I agree with you on the LLH. I would rather that than pri/sec piping. With my experience with the LLH with Viessmann the LLH promotes better condesing in the boiler than the pri/sec.

MikeyB

LLH

Thanks for your responses guys, another question in regards to the PONPC where is the best spot to place it on a LLH, on the primary side of the LLH (on the inlet of the boiler loop circ pumping into the mod con), or on the system side of the LLH ( with the system pump or pumps pumping away from the PONPC, I have seen it done both ways and was curious if there is a preferred way, I believe Siggy's books it has it connected to the boiler pump, thanks again guys 

PaulR

Expansion Tank Location

When using a hydroseparator, I prefer locating the expansion tank on the source side (boiler loop).  As the Caleffi Hydroseparator comes with a drain for the lower tap, I would leave that clear to purge small amounts of sediment that could accumulate.  Pipe in another tee and you will be good to go.



Paul

Jean-David Beyer

Primary-Secondary vs. Low Loss Header

I do not see any fundamental difference between these. They seem identical from the point-of-view of isolation of flows through the boiler from those through the heating circuits.



There seem to be some practical differences however.



1.) You do not have to fabricate the two closely-spaced-Ts if you use a LLH. This saves some labor cost -- but it does not seem to be much (10 minutes?).

1a.) An LLH can look neater.



These may depend on what kind of LLH you have in mind:

2.) It is easy to put an automatic vent valve at the top of an LLH if you want one. But since you probably want something more effective than one of those, it seems redundant to me.

2a.) It seems easy to drain dirt from an LLH.

MikeyB

LLH

Great Pic Paul, thanks, good point about the separate T connection, I have seen pics of jobs that connect the make up line into the bottom of the LLH

MikeyB

LLH

Thanks for your reply JD, I see your point, I have seen some pics on the wall where some guys updated the supplied air vent that comes with the LLH with one of better quality, maybe a isolation valve before the air vent is a good idea as well, for maint on the vent if dirt were to hang up the float,I think the drain on a LLH is a nice feature as well, and the looks of the LLH have advantages

Jean-David Beyer

That's not quite what I meant.

A little automatic vent valve at the top of an LLH is fine. What I meant by more effective was something like the 4900 series by Taco (the small ones) or a Spirovent. These remove microbubbles and dissolved air as well as the big bubbles.



The LLHs I have looked at (on the web; I do not have one) may be more effective than an air-scoop type -- I am not sure -- but I meant you might want one more effective, like those I mentioned.

MikeyB

Air Vent

Spirovent's used them, love them, great products

hot_rod

look for a separator with all

the right stuff. Dimensions are critical, barrel diameter to length, etc. A mesh, or means to collect the bubbles increases the efficiency of the air removal. Some models have extended bottom portions to provide more dirt separation ability.



The key to air removal is more than just the "device." Proper piping, sizing of the piping for velocity, location of the device, pump and expansion tank location, etc.



A quality separator, properly sized and installed will do a fine job of hydraulic separation, air elimination and some dirt separation. They are designed to be a multi purpose device, they do have limitations.



Many mod cons have air removal means included on the heat exchanger. Some are automatic float style, some manual, these also compliment the hydro separators to keep the boiler side of the piping air free.



In some cases an additional air removal device aids air removal on the distribution side. certainly air vents on manifolds and radiators at the high points in the building should be included.



A good high pressure power purge of individual zones and radiant loops goes a long way towards eliminating air problems, at initial fill.



hr

MikeyB

LLH

Great advice as always HR, thanks for your input

CMadatMe

LLH

Mikey maybe this PDF file can help you out.

MikeyB

LLH

Thanks RW, looks like good literature

Unknown

You may also want to consider.....

I some cases the Alberta Injection Tee (replaces tow closely spaced tees with 1/2 the joints)  is a better choice over a higher priced Low Loss Header from Caleffi or B&G or even Viessmann. BUt there is more to also consider, like cycle timing.



Depending on the load, zoning and boiler size, you may also want to consider a buffer tank that would act as a air separator, dirt separator, buffer tank and hydraulic separator.



I do not personally sell this brand but I really liked the piece of literature!



wheels

MikeyB

LLH

Thanks Steve, I will price out the differences between a LLH and a P/S connection and way out the labor end, the budget is a little tight, Also would like to check out the new Taco LLH, there seems to be alot of these out on the market to choose from. The system will contain 4 baseboard heating zones w/ a total of approx 53,000 btu/hr heat loss, and an indirect as well, would like to go with one of the mod cons I had mentioned in my first post, also would like to use the Grundfos Alfa w/4 zone valves. I might even want to look at a buffer tank, like a 30 gallon Boiler Buddy. Not sure what they cost but they are probably a bit more than a hydro separator

D107

If this could also serve as an indirect.......

is that possible? I know (HO here) reverse indirects can serve as buffer tanks, but could this unit be adapted? Then it would be an amazing combo unit.

dynamic

How to size a seperator

HR, how would I properly size a hydro seperator ?  I have a mod con boiler that has 1" supply and return tappings. It has a Taco 0013 as a primary pump that is factory installed. I have 180,000 btu's of load on the load side, split amongst 5 circulators.



Would I size the seperator based on a flow rate of 18gpm ? That would be a 1-1/2 seperator ?

CMadatMe

Seperator Sizing

Here is a piece of reading that should help you out.

NRT_Rob

air sep plus vent?

when we use a microbubble air separator in a system, we almost never use additional air removal vents. It shouldn't be necessary.



Can any current hydro separators reduce the oxygen saturation level of the water to the point where it absorbs air from other parts of the system? or are they just good vents?

hot_rod

to size

use this table.



I think the Boiler Buddy is another good choice that offers some "bufferance" and separation. I think the TurboMax reverse indirect also comes with 4 connections now?



hr

Jean-David Beyer

absorbs air from other parts of the system

I read that they can. See John Siegenthaler's book, second edition, pages 480 to 482.

NRT_Rob

that's what we use

I'm asking if any resorbers are built into hydro separators, or whether the air removal devices in hydro separators are simply air vents.



I don't know all the physics behind their usage though, so basically I'm just asking if any of the hydo-separators out there have air removal devices that are as good as spirovents. It may be that with simpler construction they are just as effective due to the velocity/pressure situation in the hydroseparator.. I don't know.



But If not, the vent on on the hydro sep is not serving the same function as a spirovent, and I couldn't offset the cost of the sep by dropping the spirovent.

Piper

not a munchkin

fer the love of pete...

don't know much about the knights, but i have installed a good deal of munchkins. too many service calls. in the middle of winter in the dead of night. i don't have any idea why everybody likes them so much. service contracts maybe??

triangle tube is all i install these days.