EK2 headloss numbers?

Nathan_6

I'm tearing into a cobbled together EK2 boiler that is over-sized and has major piping and zoning issues. I'm going to demob the ek2 tomorrow and start laying out the new components  and zones.  The big question is there is no boiler manual on site and Energy kinetics's has been so kind as to not have one available for download on their website.  I need to know what the boilers head-loss is so that I can properly size the circulator.  If anyone has a manual and could look that up for me that would be great or if you know were I can download a PDF of the service and install manual that would be helpful as well.



Thanks,

Steamhead

Try calling Energy Kinetics

I've heard good things about their tech support people, though I haven't had to use them myself.



With that said, I doubt the HX will have that much back-pressure. What type of system is your EK-2 installed in- for example baseboard, radiators, converted gravity etc?

Nathan_6

on my todo list this morning

Calling Energy Kinetics this morning is on my to do list I was hoping thta some night olw last night would have the answer so it would be waiting for me when I got up. :-)   The system is a oil with a poorly installed monoflo system and some some kick space heaters are gettiing added.

Robert O'Brien

EK-2

Uses a 0010,so if not using a Taco,use a pump with a comparable curve

SWEI

how big is this boiler?

EK-2s come in several sizes.  You're right to do the math -- I wouldn't trust any factory-provided pump size.

Jim Hankinson

EK-2 headloss

EK-2 is the boiler size but it has several firing rates.

The factory installed circulator is the 0010, as Bob mentioned, so why wouldn't you trust a factory provided pump size? The circs are sized not for what's needed for correct flow through the heating system, but for what's needed through the boiler. If there's significant head loss in the heating system, pipe it as primary/secondary, then you can use what ever turns you on for the loop circ.

SWEI

Boilers with factory-provided circulators

By "wouldn't trust" I certainly don't mean to imply that a factory-provided circulator will not work or will not be safe.  I do believe, based on experience, that it will almost certainly not be the optimum circulator for a particular application.  While I'm not opposed to locating a circulator inside a boiler casing, I have changed more than a few of them out in the field in order to achieve optimal delta-T (in both primary-secondary and direct-pumped systems.)



Using the the same circulator for boilers of several firing rates pretty much guarantees this will be the case, since the manufacturer can't permit their largest firing rate to be underpumped in any possible piping configuration.



In my world, the 0010 currently sees duty on primary loops of 399k boilers.

Jim Hankinson

EK-2 headloss

In over 30 years of doing it this way, it has yet to be disproved. As I mentioned yesterday, the circ is sized to the flow requirements of the boiler not the heating system. In a primary/secondary situation such as Nathan has, the circ on the boiler has very little head to overcome, just that of the boiler itself, and the injection loop.

If you use zone circs off the main loop they can be individually sized to the characteristics of the individual zones without changing the flow through the boiler.

SWEI

low-head primary loop

I'm using 0010s to move ~24 GPM through short primary loops.

SWEI

just re-read the original post

And wonder if you ever got a number for head loss?



As to the oversizing, perhaps a buffer tank with mixdown and ODR might be in order?

EddieG

ODR

EK boilers have there own manager control. Not the type of boiler you use ODR on.

SWEI

OK, so no ODR

Not sure what kind of algorithm their Energy Manager uses, but what to do about the oversizing?  Is downfiring an option?  Is even their 1.20 GPM rate too much for the load? 

EddieG

Kinda like an on demand boiler....

It is a low mass boiler. There control takes a demand from the t-stat (24V) and energizes the burner, circulator, and opens a zone valve. They make 3 sizes of HX that can take multiple nozzles to adjust firing rate. Each boiler comes with a circ. Or you can pipe the in primary/ secondary. They are set up to drop right in on a high temp. job with minimal piping. They have a factory piped in bypass, by the way.

Jim Hankinson

EK-2 head loss

Each size boiler is fitted with the correctly sized circulator for the range of firing rates. Likewise the plate heat exchangers are sized to the output of the boiler. There are 3 or 4 firing rates for each boiler with the lowest firing rate recommended for power venting only so as to avoid flue gas condensation.



In this case with an EK-2 installed where an EK-1 supposedly would have sufficed overall efficiency is only reduced by a few (2-3) per cent due to the fact that the boiler purges the usable heat out to the last active zone when the thermostat is satisfied. There is no standby loss when the system is not active.



The manager does not use algorithms in its operation since it does not have and does not need ODR. Outputs to burner and zones are based on return water temperature.



Manuals and system drawings are not available on line in order to insure that techs or installers get what they really need, not what they think they need for a particular job, also to be sure they get the most up to date information. Sometimes several drawings have to be merged for a complete job for the different aspects of it. A simple phone call with information about what's there and what needs to be done is all that's necessary.



As far as O/I manuals go, every system leaves the factory with complete installation and service manuals. Code requires that those materials be left at the site in plain view. If those materials happen to be missing a simple call to EK will get the correct info sent out, either by snail mail or e-mail.

SWEI

interesting, but I'm curious

How does the system handle minimal demand?  Say the load at design temp is 150k, so we specify an EK2 @ 175k NG.  What happens in a shoulder season when the load is 20k?

Robert O'Brien

What happens?

What happens with any non-modulating boiler? Same thing,except the residual heat is purged from boiler to house

Paul48

SWEI

It monitors return temps, and adjusts burn times accordingly.It can keep the boiler condensing at a much higher percentage of time than with ODR( they claim).

SWEI

burn times

Sounds like they're effectively doing some kind of long PWM modulation on the flame.  In a conventional boiler this would be considered short cycling, but apparently they've designed for that.  Clever.  In the example I gave above, duty cycle would be about 8 minutes per hour, though there are several ways of getting there without actually turning the boiler off.



It appears they are non-condensing.

Paul48

I'd

like to understand better what they are doing, but the info doesn't seem to be easily accessed. They claim a lot if things, but I'd like to look at it and see if it makes sense to me. One of their biggest claims is that they purge the boiler of all available heat, but I can't see that increasing efficiency as much as they claim.

chapchap70

EK2 is non-condensing

Zones are shut down when return temps get too low until the burner can bring the temperature back up like a conventional boiler. 



The pre heat from cold start, post purge and low mass (EK2 water content is 4 gallons) is what saves fuel because the boiler starts and ends cooler.  Even if the boiler runs at 180 under a load and the load is small, the boiler ends up at 140 or less when done.  The boiler temp could be at 100 or so by the time the next call a couple of hours later during the shoulder seasons.  In the summer, it only fires for a hot water call.