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SYSTEM SETTINGS 1

- SYSTEM SETTINGS 1-

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>Purge Delay

Lag Delay

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PURGE

DELAY

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Value ->

New Value

 

 

 

 

 

 

 

 

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PURGE

DELAY

---

Value -> New Value

ADJUST

PRESS TO SELECT

ADJUST

PRESS TO SELECT

ADJUST

PRESS TO SELECT

Press to

show

setting

Turn to

adjust value

Press to

select

new

Lst on

On power up, or any time the Harmony loses power, the Lead Stage will be the lowest stage in Auto Mode (that is, A first, then B, C, or D).

The Lead Stage will always be the first stage brought on and modulated when there is a call for output. As more output is needed, additional stages are added.

When less output is needed, the Lead Stage will be the first stage turned off. The bracket indicating lead stage will then switch to the next available stage in Auto Mode. For instance, if the stages were added in the sequence A, B, and C, then they will be turned off in the sequence A, B, and finally C. The lead stage will now be D when more output is needed.

PURGE DELAY Default - 1.0 min

Most fully modulating units must go through a purge cycle before they are brought on line and can begin generating heating.

After activating a new Stage, the Harmony does not adjust its modulation until the Purge Delay is over. This allows the unit to fully come on line and to begin producing output. Once the Purge Delay is over, the Harmony can begin adjusting its modulation to hold the set point.

The Purge Delay helps to prevent short cycling of a newly activated Stage. Once a Stage is activated, it MUST run through the entire Purge Delay period.

The minimum Purge Delay setting MUST be the time required for the unit’s purge cycle.

The actual Purge Delay should be set to the amount of time between when a Stage is activated, and when the Harmony sensor begins to see a change in output. This can be several minutes longer than the actual purge time of the unit.

- SYSTEM SETTINGS 1-

Purge Delay

>Lag Delay

Standby Time

--- LAG DELAY ---

Value -> New Value

--- LAG DELAY ---

Value -> New Value

ADJUST

PRESS TO SELECT

ADJUST

PRESS TO SELECT

ADJUST

PRESS TO SELECT

Press to

show

setting

Turn to

adjust value

Press to

select

new

LAG DELAY

Default - 0 min

Set the Lag Delay to 0 min when two or more Stages will generally be needed to hold the load.

The Lag Delay requires the previous stage to remain at 100% modulation for the full period of the Lag Delay before another Stage can be activated. For example, if the Lag Delay is set to 10 minutes, the Lead Stage would need to remain at 100% modulation for a full ten minutes (never backing down to even 99%) before a lag stage could be activated.

The Lag Delay is useful in installations where one unit should usually have enough output to hold the load unless it fails or load conditions become extreme.

The Lag Delay overrides the value of the Modulation Point selected for each stage. Regardless of that setting, the previous stage must reach 100% and stay there before another Stage can be activated.

The full Lag Delay must always elapse regardless of what happens to system temperature. Therefore, set the Lag Delay to 0 min if you want smooth set point control from multiple units.

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Lochinvar Harmony PURGE DELAY Default - 1.0 min, Lag Delay, Default - 0 min, System Settings, Lst on, Press to select new