system 2000

todd s

I have to look at an ek2 tomorrow thats been overheating in a couple zones. The boiler appears to have been piped as per instructions with one noticeable differance. The main pump is a 0011 rather than an 007. The zones that overheat are the first two on the manifold. I was thinking that the pump has been pushing through these two zones(v8043) as the path of least resistance. I'm questioning this because I was told that the plate hx for the domestic acts as a bypass and wouldn't allow this to happen. What does this sound like? a partially plugged hx? customer claims to have plenty of hw. How do you test the hx to see if it is plugged? Or could this be too much pump wearing away at the springs on the zone valve and allowing flow past?

Glenn_3

Might also want to make sure anticipator on stat(if they have one) is set correctly

Constantin

Someone mentioned TRV's being overpowered before...

...I guess the only way to be sure is to hook up a set of pressure gauges to see if that HX is acting as a differential bypass or not. I don't have the piping diagram in front of me, but the extant "differential bypass" sounds suspect.

Based on the size of the pump and the head it is capable of creating, I share your suspicion that it's forcing the first two manifold valves open. Is a 011 really necessary in this application, or was it merely installed to "prevent" callbacks?

Mitigating the excessive head pressures (if that's what the problem is) could be as simple as replacing the 011 with a VS model that senses the pressure and adjusts its speed accordingly. Very little additional work and a happy TRV system (if the excessive head pressures are what are causing the problem).

As for testing the HX, pressure gauges at inlet and outlet should tell the story. If there is a huge differential, then the HX is plugged and needs to be cleaned. Vinegar will get the calcium out. However, the heating side of the HX should be clean - it's supposed to be dead water.

Steve Eayrs

The 0011 is the proper pump for the EK-2

The smaller EK-1 uses the 007.
The bypass through the heat exchanger is the bypass on this boiler, and if its not bypassing, either the heat exchanger is plugged, or the ball alve is closed.

We install drains, after this ball valve, but before the heat exchanger, so you can backflush the heat exchanger by closing the ball valve, and opening the drain. This of course will tell you if the heat exchanger is plugged or not, since it will of course not flow too well if plugged. If they have bad water it very possibly could be plugged.


Do not put a smaller pump on the boiler. IF none of the above is the problem, than you have a couple of bad zone valves, maybe a thermostat anticipator problem like already mentioned. You may also have a problem if you use slow acting zone valves, like taco, on these boilers. They need fast acting vlvs like honeywell or erie to cycle the boiler right.


If installed right these are great little boilers. Have installed around 250 or so of them in the last 15 or so years with very little problems.


Might also add that we have ran into a number of these heat exchangers being plugged, that are hooked up to some sort of non-barrier tube radiant floor system. These are never a dead water system, but eat away at the steel heat exchangers, and plug things like heat exchangers, on the boiler side.


Steve

todd s

EK2

This is a standard baseboard sytem with the zone valves on the supply manifold at the boiler. They are Honeywell v8043e and they are definitley bypassing, the t-stat wires were even disconnected over the summer to test it. I'm thinking that the HX is getting plugged, but it doesn't seem like it should on the boiler side. I could see the domestic side getting plugged but I don't see why the "dead" water in the boiler would plug it. The system is all copper with fin tube except for a small staple up bathroom(that's a whole other issue - "when injection pumping goes bad") I think its watts tubing there but I'll verify that today. I suppose we could swap the zone valve heads that are bypassing with two new ones, or maybe we could see the springs slightly flexing when the pump is cycled. Thanks for the suggestions I'll post back later. Todd

Steve Eayrs

Todd

ON these boilers the pump will always be running, whenever there is any kind of call for heat.

Maybe its not the heat exchanger. Are you sure the ball valve is open on the bypass piping? If he heat exchanger is plugged you will not get very much dhw. Try running the dhw out and when it calls for heat, the inlet side of the ss exchanger should be real hot and if it not plugged, the outlet should be a lot cooler.


Steve

todd s

Ek2 Follow up

After an hour of poking around with the HO and tracing pipes I decided where to start. First, while we were talking and looking around I noticed that the burner was on and off several short cycles the circ(an 0010 actually) was running non stop. I decided to call Energy Kinetics to go through the system manager check. I was able to go through the test procedure with their techline,it checked out. I turned everything back on and other than tightening the resistor on the dhw nothing appeared out of the ordinary. Well that seems to have stopped the burner cycling and circ running all the time. Next was to check the zone valve, rather than to scratch my head wondering if the ball was ok or the springs weak, I changed the whole unit. Did I mention nothing but the zone valve covers were labeled and there were no isolation valves? I fired the unit back up and purged everything and it appears to have stopped the overheating zone. At this point it seems like problem #1 was a combination of a loose connection causing the erratic manager behavior and possibly a weak zone valve allowing enough leakage to overheat the zone. We'll see in a few days. Thanks to your posts for keeping my train of thought inthe right direction and to Charlie at EK for spending the time on the phone. If this does the trick the next task will be straitening out the injection pumping system for the radiant bath.

Nron_9

Bypass

flat plate heat ex have a restriction in them and with the 011 pump changeing the zone valves will work for a while till the springs weaken , then same problem , if the pump runs all the time add a pressure bypass valve they keep excess pressure from weareing out zone valves

Steve Eayrs

The pump does not run all the time.

Just when there is a call for heat, dhw or other. The pump is actually a 0010 not 0011. The units work fine as designed, without adding a second bypass other than the existing ss heat exchanger. To do so would create a possible problem when the system calls for dhw and can't keep up, because of the reduced flow thru the heat exchanger.

Steve

john_55

bypass

ek2 can have the plate ex on its own zonevalve and a full 34 bypass loop instald. This does 2 things the plate ex wont block up as quick and will ease up pressure on the other zones. If you have room for another zone on manager

Todd_9

It's happening again

I spoke to the customer today and he said that one zone was overheating today, this was a differant zone. I stopped by and the burner light and the circ light were both on and the boiler was up to 220°. I shut off power and the system seemed to reset itself. I went through the manager test last week and it semmed ok. What could be causing this?