System 2000 continuously heating zone 3

betterl8

Hello,

Wondering if anyone can help me with this..

My System 2000 has been continuously heating my family room zone 3; I've tested the thermostat and even changed it out with another to eliminate that being the problem.
I also had a tech look at the zone valves; he did not think they were the issue but was unfamiliar with the system 2000.
I have 4 zones; zone 3 is the problem (i think). I started running my own tests and ensured all other thermostats were off, apart from the one I was testing. When looking at the Energy manager i see the signal from the thermostat on the left side of zone 3 calling and after a few mins the burner starts, and a few more mins I see the right side light come on. The strange thing is that the Zone 1 light starts flashing (solid for 2 seconds then does two quick flickers). After i turn the thermostat off on zone 3, I see both lights go out on the energy manager for that zone, but the zone 1 light on the right side stays solid. My hunch is this is the energy manager board causing the issue but i thought i would ask as i'm no expert in this area.
Also the Zone 3 pipe is always warm to the touch although its turned off.

neilc

let's see your zone valve, and that pipe job around it that's always hot,
is the manual lever easy to swing, indicating the valve is open?
take a wire off terminal 1, or just switch off the boiler service switch, does the valve shut? the manual lever is harder to swing?
maybe the head is jammed open? can you remove the head?

betterl8

Here are the zone valves, the one in red is the problem. Do you mean to turn the lever up lear the pipes?

neilc

there's small levers under those actuator bodies,

when the thermostat calls for heat, the levers will swing freely,
with the thermostat off, the lever would be resistant as you swing the lever to manually open the valve,

HVACNUT

@betterl8, it's doubtful that the Manager is the issue. 
Zone 3 is somehow getting a signal to call for heat. The left side T3 light indicates that. Once the burner starts and reaches 140°, the Z3 light will illuminate and the Zone 3 zone valve will open. When the Zone 3 signal (or any zone) is interrupted, Zone 1 seems to be programmed for "Zone Purge", which dumps BTU's into the space rather than it getting wasted out the chimney or through jacket loss.
So the sequence seems perfectly normal. What's not normal is that the sequence is happening when it's no supposed to.
What type of thermostat? Smart? 
Check the wiring between the A1/ Z3 terminals and the thermostat. Any splices? It seems like an intermittent short, or a power robber thermostat. 
When you swapped it with another thermostat, did you swap the sub base as well?

betterl8

i swapped my smart thermostat (nest learning) with a basic battery powered one. It's a 2 wire system. Thanks for letting me know all seems normal with the board. I will keep the standard thermostat in zone 3 for a few days and keep an eye on it. Also is it normal for the circulator to be on all the time, the Inducer light flashes now and again too.

HVACNUT

betterl8 said:

i swapped my smart thermostat (nest learning) with a basic battery powered one. It's a 2 wire system. Thanks for letting me know all seems normal with the board. I will keep the standard thermostat in zone 3 for a few days and keep an eye on it. Also is it normal for the circulator to be on all the time, the Inducer light flashes now and again too.

Ok, I'm not saying it's Nest related (wink wink, nod nod) but it might be something to look into. Especially if there's no Common.I don't know the ohm rating needed, but...

rick in Alaska

Unless I am mistaken, when a zone call ends, that zone stays on for the purge, and not another one. So zone one should not be coming on. And the circulator should stop when the zone call is done purging. I am going for a defective board myself. Roger from System 2000 will probably check in tomorrow to verify.
Also, You need to have someone check you system pressure right away as the gauge looks like it is showing about 40 psi, which is dangerously way too high. My guess is a bad gauge, which is common, but you need to check it out immediately.
Rick

betterl8

Thanks guys, i will try to get it looked at this week, I had a guy out yesterday to do a cleaning and he didn't mention the pressure but was also not an expert with the system 2000's.

szwedj

Probably the two most common reasons for a zone to start over heating is either a bad zone valve which is letting hot water pass by even when it is closed or a power stealing thermostat, especially Nest's that have been installed. Basically when that Nest is "stealing" power to charge, it creates what is known as a ghost call to the manager. A ghost call is typically not enough of a call to start a heat demand to the system manager but is enough to trick it into thinking it was the last zone calling and cause it post purge to that zone.

Roger

@betterl8 , to me it sounds like you describe two issues going on.
One is that the pipe on zone 3 is hot all the time. This is most likely a bypassing zone valve (stuck open, debris, malfunctioning and won't close).
Two is that zone 1 comes on briefly and then turns off repeatedly. This is a typical charging thermostat ghost call (it draws enough power to look like the thermostat is on); this can sometimes happen with a thermostat with a dead battery, not just WiFi thermostats; check the battery and/or address the WiFi power stealing as we show here. Here's the reasoning: Because that zone looks like the thermostat is calling, at the end of any thermostat call the thermal purge will swing over to zone 1 because it's the last zone to call. The other evidence is that you said that it takes a few minutes for the burner to start. There is a burner restart delay, so zone 1 thermostat on and off repeatedly will cause a delay in the burner start time for any zone that calls. The burner will start with a continuous thermostat call from any zone, but it may be delayed if zone 1 just appeared to turn off. This prevents odd things from happening with a chattering thermostat.
Here are some other diagnostics to test a bypassing zone:
Run hot water without any heating zones active. Carefully feel the pipe/tubing after the zone valve to see if it gets hot, which would indicate the zone valve is bleeding through (you described this). This can happen if there is a problem with the zone valve or if a Wi-Fi thermostat is charging and creating a ghost call. If the zone valve is powered open, the lever on the zone valve will swing freely. If it is not powered on, it will be much more difficult to move the lever. If the zone valve is bypassing and it is not just some debris that can be cleared, replace the zone valve.
Roger

betterl8

Thanks @Roger, I removed both nests and let the system rest, then did your water test, the zone 3 pipe started heating up, i could not open the valve, I had a tech out on Saturday who took it apart, so I'm assuming the valve is the issue and will order another. I also think as you mentioned the Nests could be causing an issue as they both have been complaining about low battery recently. So I also ordered the 588 resistors that are recommended here: https://energykinetics.com/wp-content/documents/display-manager/nest-power-sharing-wiring.pdf. Can you tell me from the pictures i provided that the wiring is correct... From the description in this link, all red wires should go to A1, and all white wires to the relative zones. My manager has all colored (spliced to red, as shown in the other picture), going to the relative zones. I'm assuming i will switch this when i get the resistors? Also It was mentioned that my system gauge of 40 psi is too high so i probably need to get that checked too

.

szwedj

@better18 Let me try and explain the wiring assuming that this is heat only (not heat and AC) and you only have two wires available going to each thermostat. Now regardless of the actual colors of the wires being used, at the system manager you have terminals A1, A2 and Tx (ie T1, T2, T3, T4), at the Nest thermostat you will use Rh and W. You want the wire (regardless of color) connected to the Rh terminal at the Nest to be connected to the A1 terminal at the Manager. And you want the wire (regardless of color) connected to the W terminal at the Nest to be connect to the thermostat input being used for that zone, T1, T2, etc at the Manager. Now for the resistor, the resistor has two leads, one end gets connected to the thermostat input being used at the manager, T1, T2, etc. and the other end of the resistors connect to the A2 terminal at the Manager. As mentioned, don't get hung up on the wire colors, just make sure whatever color the wire used is, it is connected to the correct terminals as described. Hope this helps. Feel free to email me directly at jszwed@energykinetics.com