tekmar 365 Mixing Control - Manual (Page 5)

Copyright © D 365 - 06/00 5 of 16
The control accepts a zone input signal from a tekmar 10K Zone Control which monitors the
indoor temperature of all zones – as well as the outdoor and supply temperatures – and shifts the
Heating Curve (and the WWSD point) up or down to fine adjust the system supply water
temperature for whichever zone requires the hottest supply water. The Occupied and Unoccu-
pied dials are only functional if an external heat demand is given and the dial setting is higher than
the zone control desired temperature.
Sequence of Operation
When the Mixing Control 365 is powered-up, the "Power" light will come on and the control will turn on all
LEDs for five seconds. If no errors are detected, the control enters the operating mode.
Once in operating mode, the control determines whether to operate in Reset or Setpoint mode based on
the setting of the Reset/Setpoint DIP switch.
If the control is configured for Setpoint it will monitor:
• a Universal Sensor 071 to continually monitor the system supply water temperature.
•
Optionally, a Universal Sensor 071 to continually monitor the boiler return water temperature.
If the control is configured for Reset it will monitor:
• an Outdoor Sensor 070 to continually monitor the outdoor temperature.
• a Universal Sensor 071 to continually monitor the system supply water temperature.
•
Optionally, a Universal Sensor 071 to continually monitor the boiler return water temperature.
• Optionally, the indoor temperature can be monitored through the use of:
(a) - a tekmar 2K RTU or 10K Indoor Sensor 074 (DIP switch in "Indoor Sensor" position) or;
(b) - a tekmar 10K Zone Control (DIP switch in "Zone Control" position)
• While monitoring all of these temperatures, the control recognizes the following temperature conditions
and inputs and will respond as described. During operation, the lights of the control will indicate
operational status as illustrated.
2K RTU function Selector switch = Indoor Sensor
The control will monitor the indoor, outdoor and supply temperatures, and shift the Heating Curve
(and the WWSD point) up or down to fine adjust the system supply water temperature whenever
the room temperature is different than the setting of the RTU dial. The Occupied and Unoccupied
dials are not functional. A Setback RTU 308 must be used if Unoccupied schedules are desired.
tekmar Zone Control function Selector switch = Zone Control
Indoor Sensor 074 function Selector switch = Indoor Sensor
The control will monitor the indoor, outdoor and supply temperatures, and shift the Heating Curve
(and the WWSD point) up or down to fine adjust the system supply water temperature whenever
the room temperature is different than the setting of the Occupied dial. When switched into
Unoccupied mode, the "UnOcc. Switch" light will come on, and the control will operate at the
temperature of the Unoccupied dial setting.
90
70
50
30
10
Power WWSD
UnOcc.
Switch
Min.
Return
Boiler
Heat
Demand
Max. or
Setpoint
Pump
% of full
output
Test
Setpoint
Reset
1 2 3 4
?
Selector Switch = Reset
Reset Permanent Heat Demand
Indoor Sensor
Boiler on when 10% open
1 2 3 4
Reset Permanent Heat Demand
Indoor Sensor 1 2 3 4
Boiler on when 10% open
Reset Permanent Heat Demand
Indoor Sensor 1 2 3 4
Boiler on when 10% open
Zone Control
Boiler on when 25% open
External Heat Demand
Setpoint
1 2 3 4
Heating Operation (Reset Mode)
When the control is in the reset mode, its main function is to reset the supply water
temperature based on the changing outdoor temperature.
External Heat Demand signal
A heat demand signal is caused by either 24 or 120Vac applied to terminals
Heat Dem — Heat Dem (1 and 2).
AND/OR
Dem Dem
Heat
1 2
Zone Control
Boiler on when 25% open
External Heat Demand Setpoint
1 2 3 4
Selector Switch = External Heat Demand
An active (calling for heat) 10 K Zone Control connected
to terminals
Com Sen — 10K Sen (14 and 15).
Permanent Heat Demand signal
A heat demand signal is continuously present unless a10K Zone Control is connected to terminals
Com Sen — 10K Sen (14 and 15). (If a10K Zone Control is connected, there will only be a heat demand
present when it calls for heat)
Selector Switch = Permanent Heat Demand
Zone Control
Boiler on when 25% open
External Heat Demand
Setpoint
1 2 3 4
12 13
2K
RTU
Com
Sen
16
Sup
Sen
17
Out
Sen
18 19
Com
–
Ret
Sen
11 10
+
4-20 UnO
Sw
14
Com
Sen
10K
Sen
15
Reset Permanent Heat Demand
Indoor Sensor
Boiler on when 10% open
1 2 3 4
Occupied/Unoccupied dial function
With no indoor air temperature feedback, the control will monitor the outdoor and supply
temperatures. The Occupied and Unoccupied dial settings become the WWSD points.
When in Occupied mode and the outdoor temperature is warmer than the setting of the
Occupied dial, the control enters WWSD. When switched into Unoccupied mode – Connect
(short circuit) terminals
UnO Sw — Com Sen (13 and 14) together by a switch or isolated timer
relay contacts (tekmar Timer 030) – the "UnOcc. Switch" light will come on, the Occupied dial
will become inactive and the Unoccupied dial will become active as the control starts to
operate at the temperature of the Unoccupied dial setting.
12
10K
Sen
2K
RTU
Com
Sen
16
Sup
Sen
17
Out
Sen
18 19
Com
–
Ret
Sen
11 10
+
4-20
15 13 14
UnO
Sw
Com
Sen