Test – tekmar 422 Universal Reset Module User Manual
Page 15

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© 2007
D 422 - 08/07
Test
Press and Hold 
for 3 seconds
Test
Press and Hold 
for 6 seconds
Max Heat
The control has a function called Max Heat. In this mode, 
the control turns on and operates the system up to the 
maximum set temperatures as long as there is a demand 
for heat. tN4 thermostats operate to meet the occupied 
setting +5°F (3°C). The control operates in this mode for 
up to 24 hours or until the Test button is pressed. Use this 
mode to run the circulators during system start-up to purge 
air from the piping.
• 
• The Mix 1, Mix 2 and Mix 3 Maximum settings are avail-
able in the Adjust Menu when in Max Heat.
HAZARD
Access to the Test button requires the removal of the 
front cover and exposes hazardous voltage while the 
control is powered. Only trained, qualified and competent 
personnel should operate the Test button.
To enable Max Heat:
Press and hold the Test button for more than 3 seconds 
and less than 6 seconds.
If there is a demand for heat, the ‘TEST’ and ‘MAX’ segments 
are displayed on screen and the control will turn on all 
outputs for up to 24 hours.
If there is no demand for heat, the ‘TEST’ and ‘MAX’ 
segments are still displayed but no outputs are turned on 
until there is a demand for heat present.
To Cancel Max Heat:
Press the Test button to cancel Max Heat manually or wait 
24 hours and the control will automatically leave the Max 
Heat mode.
Zone Test
In Zone Test mode, each tN4 device is individually turned 
on one at a time. The control tests each zone for up to 5 
minutes of no button activity. Use this feature to purge air 
out of each zone and assist in troubleshooting.
HAZARD
Access to the Test button requires the removal of the 
front cover and exposes hazardous voltage while the 
control is powered. Only trained, qualified and competent 
personnel should operate the Test button.
To enable Zone Test:
1.
Press and hold the Test button for more than 6 seconds. 
The control displays ZN TEST OFF.
2.
Press the Up button to change the display to ZN TEST 
ON. After 3 seconds, the boiler, all pumps, and the 
mixing valves are shut off.
3.
The control operates stage one of the tN4 device with the 
lowest address number. Device number one of the boiler 
bus (b:01) has the lowest address number and device 
24 of bus 3 (3:24) has the highest address number. All 
other tN4 zones are shut off.
4.
Pressing the Up button will turn off stage 1, and turn on 
stage 2 of the same device (if that device has a second 
stage) or turn on stage 1 of the device with the next 
lowest address. The Down button can be pressed to 
move to a device with a lower address number. The Up 
and Down buttons will only move through devices on 
the same bus.
5.
Press the Item button to switch busses. The Up and 
Down buttons can then be used to move through the 
devices and the heating stages of each device on the 
next bus.
6.
To cancel the Zone Test, press the Test button. Once 
the Zone Test ends or is cancelled, the control resumes 
normal operation.
Test
Wait
3
seconds
Test
Hold
for 6
seconds
