Energy Kinetics System 2000 EK1 problem

flannel

I have an Energy Kinetics System 2000 EK1 boiler since I bought my house in early 2010. It's an oil-fired unit and plumbed as a single zone plus hot water. I love this unit and it's been extremely energy efficient and trouble-free for my old house.

Recently, however, I noticed it's misbehaving where the zone #2 thermostat will call for heat (manager light turns on), the burner and circulator both kick on (both lights on), the burner runs for a while and boiler heats up, but the zone valve lights never kick on or open the zone valves. Eventually, the high limit aquastat triggers (I tested voltage and confirmed) and the burner shuts off. When this happens, the manager burner light and circulator lights stay on. After 15 seconds, the burner fires again but only lasts for ~1 minute, and then this cycle repeats.

Now, if I open the zone valve manually and leave it open, the burner fires continuously and the house gets warm until the thermostat no longer calls for heat.

This issue also doesn't occur when the hot water tank calls to heat domestic water. It runs exactly as it should with no issues. The left and right side lights come on as expected until the water is heated.

As a test of the manager, I shifted the zone #2 input and output wires down to zone #3 (with disconnected power, of course). Unfortunately, this didn't resolve the heating issue.

In addition to the aquastats is there another sensor wired into the manager that would prevent the zone valve from triggering? Are there any Energy Kinetics gurus that can suggest troubleshooting tips to isolate the zone #2 problem?

Thank you!

EBEBRATT-Ed

Not all that familiar with EK but how do you know it isn't just a bad zone valve?

Find a spot to pick up 24 volt power and run it directly to the zone valve with no controls to interrupt the power and drive the valve open and closed

flannel

Thanks. I disconnected everything and attached 24V to the zone valve and it fully opened as expected until power was removed and then it fully closed.

Regarding the system manager, the image below is what it looks like. The left LEDs light when a zone or hot water (zone 1) thermostat calls for heat. The right LEDs light when the zone or hot water circuit is active.

Hot water is always the priority so only if zone 1 is not calling for hot water do other zones get attention even if the thermostat is calling for heat. My hot water zone works fine and with left and right LEDs lighting properly. After these turn off, and the left hand zone 2 (or zone 3 when swapped) is lit, the burner fires as expected, but the right zone 2 LEDs don't ever light up and therefore the zone valve doesn't ever open.

I think what happens then is the boiler circuit hits the upper temperature limit without the flow and the burner cuts off.

Everything I've read suggests that these System Manager boards are pretty robust and not prone to failure. Anything is possible but I still suspect some input (e.g. sensor, aquastat, etc) to the board may be the root cause. Could the main circulator not be running properly? I can feel a vibration so I think it's running fine.

SuperTech

It might be time to call your service provider. I'm sure that you have had a service provider perform annual maintenance, replace the oil filters and burner nozzles, set combustion to the manufacturer specifications?

The zone valves don't open until the boiler circulates water through the bypass for about 90 seconds. Once the boiler is hot the zone valves open. Perhaps you might have a plugged up or restricted bypass? Has your service provider recommended anything so far?

HVACNUT

@flannel , the pic shows the Classic Manager. Is that what you have?

How did you apply 24 volts to the zone valve? Did you use the transformer on the Manager? If the transformer is good, then check for a loose splice or connection.

The water heater cycle runs normally because its all line volt (120 vac) controlled. The heating zones are 24 volt controlled. So we know the zone valve opens when 24 volts is applied. And I'm assuming the 24 volts came from the system transformer. So that leaves the wiring.

flannel

@HVACNUT Thanks. Yes, I have the Classic Manager. For testing the zone valve, yes, I pulled the 24 volts from the manager transformer (with the manager lines disconnected). Multimeter reads ~24V AC from the transformer.

Robertw

@flannel

Good morning.

Do you have a wire connected to P terminal on the left side of the manager? If so, shut off the power and disconnect it. Cap the wire safely and try the heat zone again. This wire puts the manager in hot water priority. Safe to run with it disconnected as most often priority is not needed.

Any questions Dm Me.

flannel

@Robertw Perfect. Both hot water and heating on zone 2 are behaving properly again. Thank you so much! You Energy Kinetics guys are awesome.

That line is fed from a Honeywell L4081A dual aquastat. Does it suggest a bad aquastat or low limit adjustment may be needed (currently set to 160F)?

Robertw

That's correct. Try the adjustment and replace if needed.

Glad to help.