Trane classroom unit ventilator problem

[chillwater]

I am troubleshooting a DX cool/ Hot water heat system with a ZN510 Board.
The service call is no heat. The fan runs continously and will not shut off using the built in timer. I can shut the fan off and on using the on/off switch on the stat. I can cycle the unit between occupied and unoccupied mode on the stat. All Functions work when the test button on the board is used. Any ideas. Do I need to access the programing on the board. If so not being an owner of rover software and never using it ,is it worth purchasing. I can from Trane. Does it require training to use.

[jdcoolj]

There have been quite a few miswiring issues from the factory on these units. before you purchase rover check the wiring from the timer to the zn. Also sometimes the the wires on the timer contacts have to be switched from N/O to N/C or vise versa. if you turn the timer to on=occupied does the unit turn off? Give about 30 seconds. If it turns off just switch the wires.

[chillwater]

Checked today with no results. Any other thoughts. Thanks

[jdcoolj]

Now I would suggest purchasing Rover Service Tool or bringing in Trane to check out your problem.

[chillwater]

Thanks JD. That seems to be the general consensus.

[nytrane]

Are you sure its a zn510 and not a zn520. The 520 runs the fan cont when occupied

[chillwater]

Its a 520.