FX-PCV1620 question

[DST-Tech]

We are currently commissioning a job that has 16 VAV's with reheat using the FX-PCV controllers. We also have an FX16 controller running the AHU. We are supposed to be using a Warmup-Cooldown mode upon initial startup of the system. The FX16 is setup properly to do this, but we are having issues getting the VAV boxes to open wide up when the FX16 calls for either mode. I can see that the FX-PCV has Warmup-Cooldown settings, but we cannot seem to link this to the FX16 command. Is there a point that we are missing in the FX-PCV that I can link to my FX16 Warmup-Cooldown that will tell the boxes to go wide open. I do not want to override the dampers open. I would rather do it the "right" way. We are not too experienced with the PCV and I cannot find any technical literature on this particular feature. Any insight? Thanks.

[The Reaper]

There is a point named WC-C which should be able to be written to. It has the states Warmup, Cooldown, Coast and Normal. You can see the point in commissioning mode under Network Inputs. FYI, I haven't done this personally but I think it will work. Good luck.

[DST-Tech]

I think we tried writing to that point as it shows up as a Boolean Writable, but it went into Fault until we removed our command. There's got to be a way to do it; we will keep trying until it works. Thanks.

[ControlY0urMind]

There should be a WC point that is an enum.

Are these tied into a JACE?

Are you getting an "Access Denied" Fault message on the point?

If so, to get rid of the fault when writing to points, you can go into the properties of the point in Facility Explorer and change it from "Present Value" to "3113" (manually type it in) and it will accept it.

[The Reaper]

There should be a WC point that is an enum.

Are these tied into a JACE?

Are you getting an "Access Denied" Fault message on the point?

If so, to get rid of the fault when writing to points, you can go into the properties of the point in Facility Explorer and change it from "Present Value" to "3113" (manually type it in) and it will accept it.

ControlYourMind is 100% correct. Bring the point in as an enum writable. The 3113 is a known issue with PC Series controllers and Jaces.

[DST-Tech]

Working on one now. I deleted and brought the point back as Writable and it takes the command. I did not get the Write error on this box. I told it to go into Cooldown Mode and the box states that it is. I still need to verify all the data. I am going to get one working 100%, then hopefully drop the points in the other ones. We are connected locally to an FX60, the through the building's house network to an FX Server. Thanks for the help.

[Norriski Tech]

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[Norriski Tech]

Sorry fat fingered the enter key there!! So I take it that your air-handler has heat?? As stated proxy the point in as 3113 instead of present value, that I had to learn the hard way. I'm in the middle of a 4 story building retro-fit, with 77 PCV-1620 controllers. I also used system-mode and wrote to the purge mode for building purge. It works good, my AHU doesn't have heat so the warmup command to the vav's is basically occ-mode.

[DST-Tech]

The AHU does have heating and cooling, typical mixed air AHU with enthalpy economizer. Seems that we also have another issue with the PCV. Three of the sixteen control Fin Tube Radiation zones. They are setup as two position valves, which should open first, then the reheat will open if the zone is not satisfied. We can get the BO's to pull in and open the valves, but they don't want to release. We even connected with the laptop in commissioning mode and can override the valve open. When we go to close it, the software indicates that the BO is off, but it stays latched on.

[The Reaper]

The AHU does have heating and cooling, typical mixed air AHU with enthalpy economizer. Seems that we also have another issue with the PCV. Three of the sixteen control Fin Tube Radiation zones. They are setup as two position valves, which should open first, then the reheat will open if the zone is not satisfied. We can get the BO's to pull in and open the valves, but they don't want to release. We even connected with the laptop in commissioning mode and can override the valve open. When we go to close it, the software indicates that the BO is off, but it stays latched on.

Those outputs are triacs. Try using an isolation relay. We use isolation relays on all triac outputs because of this issue.

[Norriski Tech]

Yes what reaper said.

[DST-Tech]

We are using relays. It has been a habit ever since DXs came out with all Triacs on their DOs. We are also driving multiple valves from each box, so relays were a must. I will be on site myself in a couple of days, so I can make sure it isn't user error.

[sycontrol]

We are currently commissioning a job that has 16 VAV's with reheat using the FX-PCV controllers. We also have an FX16 controller running the AHU. We are supposed to be using a Warmup-Cooldown mode upon initial startup of the system. The FX16 is setup properly to do this, but we are having issues getting the VAV boxes to open wide up when the FX16 calls for either mode. I can see that the FX-PCV has Warmup-Cooldown settings, but we cannot seem to link this to the FX16 command. Is there a point that we are missing in the FX-PCV that I can link to my FX16 Warmup-Cooldown that will tell the boxes to go wide open. I do not want to override the dampers open. I would rather do it the "right" way. We are not too experienced with the PCV and I cannot find any technical literature on this particular feature. Any insight? Thanks.

From JCI doc on what it takes to make the PCV go into WC-C of warm up:
WarmupCooldown Determination
This module determines the effective WarmupCooldown status for single duct VAV applications by evaluating the
Network Input and the automatic Warmup mode based on the supply air temperature. The module issues a warmup
status ANY TIME the SA-T (Supply Air Temperature)meets the requirements necessary for warmup (that is, both
SA-T and ZN-T are reliable and SA-T > [ZN-T+Differential]). If both SA-T and ZN-T are reliable and the SA-T is not
warm enough to trigger warmup, the WC-C (WarmupCooldown) network input is not allowed to force warmup
(remains in Normal). The module state output is the effective WarmupCooldown mode for the application.

The differential is a point too that you can set.

You can find this in JCI LIT-12011147 page 678