18
Heat-Timer Corp.
059040-00 C
ModulatIng Mode
Normal, Parallel
Default: Normal
Button:
MENU/<System Startup>/..../Modulating Mode
• Some modulating boilers perform better as their modulation increases. For these units, it is
advantageous to run one unit at high modulation than several units at lower modulation. If
the units used are of this type, select Normal. This is the recommended setting for typical
steel and cast iron boilers or boilers with low turndown ratios.
- MODULATING MODE -
Normal
Parallel
BACK
▲
▼
SAVE
• There are many condensing boilers that run more efficiently at lower modulation. If it is more energy efficient to run several units
at lower modulation than one at high, select Parallel. This is typically used on water-tube boilers, low mass boilers, or burners with
high turndown ratios.
• For best Parallel performance, set the Modulation Start % to be equivalent to the lowest firing rate of the boiler multiplied by 2.
That is if the lowest firing of the boiler was 20%, set your Modulation Start% to 40%. See page xx.
• If Parallel is selected, it is always preferable to set the Lag Delay to 0. See page xx.
PROVE/DHW SHARING
Prove
DHW Priority
DHW No Priority
No Priority (Summer)
BACK
▲
▼
SAVE
prove/doMestIc Hot Water (dHW) prIorIty
Prove, DHW Priority, DHW No Priority, No Priority (Summer)
Default: Prove
Button:
MENU/<System Startup>/..../Prove-DHW Sharing
• This setting determines the functionality of Input Terminals 29 and 30.
• When Prove is selected, the Mini-MOD will not start any boiler stage unless Prove terminals
are connected. However, it will allow the System relay to function normally.
• Using those terminals to connect to an aquastat for a Domestic Hot Water call and selecting any of the DHW options will raise the
calculated water temperature to the DHW Set Point (See next setting).
• However, Domestic Hot Water Priority option de-energizes the SYS relay during domestic hot water calls for a period of one hour.
If after the priority period the DHW did not expire, the SYS relay will energize providing heat to the building and the temperature
target will remain at the DHW Set Point. After the DHW call expires, the set point will drop to satisfy the reset ratio or set point.
• Domestic Hot Water No Priority allows the SYS relay, mostly controlling a primary system pump, to remain energized during a
domestic hot water call (aquastat call on terminals 29 and 30). However, in Summer, Shutdown, No Tstat call for heat, or when
outdoor temperature is above Outdoor Cutoff, a DHW call will energize the SYS relay. After the DHW call terminates, the SYS
relay will continue to run for the Run-On period before turning off.
• Domestic Hot Water No Priority (Summer) behaves the same as the DHW No Priority. The only difference is that in Summer,
Shutdown, No Tstat call for heat, or when outdoor temperature is above Outdoor Cutoff, a DHW call WILL NOT energize the SYS
relay except for the Run-On delay after the DHW call ends.
doMestIc Hot Water set poInt
(availaBle wiTh any of The Dhw prioriTy opTions)
Adjustable from 140
º
F/ 60
º
C to 200
º
F/ 93
º
C
Default: 180
º
F/ 82
º
C
Button:
MENU/<System Startup>/..../DHW Set Point
• On a DHW call, the Mini-MOD will raise the target to the DHW Set Point until the DHW
call expires.
- DHW SETPOINT -
180
o
F
[
]
BACK
▲
▼
SAVE
- SETBCK/SHUTDOWN -
Shutdown/Disable
Tstat/Enable
Setback
BACK
▲
▼
SAVE
sHutdoWn/tstat/setback Mode
Shutdown Input, Tstate Input, Setback Input
Default: Shutdown Input
Button:
MENU/<System Startup>/..../Setback\Shutdown
• The Mini-MOD has two levels of heat, a Normal/Day and a Setback/Night. The Normal
is good for when buildings are occupied and people are active. The Setback/Night holds a
lower system temperature for night periods or when buildings are unoccupied.
• When Shutdown or Tstat are selected, the Day/Night Schedules (See "Day/Night Schedules" on page 25.) will be available in the
operating menu. Terminals 31 and 32 will function as a Shutdown (Turn off boilers when shorted) or as a Tstat (Turn off boilers
when opened). However, a call for DHW will bring the boilers on.
• When Setback is selected, the External Signal option will switch the Mini-MOD to Setback mode when terminals 31 and 32 are
shorted. This allows an external device or control to provide the setback signal. No scheduling or boost menu options will be
available with Setback.
