Weil-McLain BMC-6X operation manual Ignition %, Modulation Start %, Copy Settings Boiler a only

BMC and BMC-6X Installation and Operation Manual

Auto - The BMC will control the boiler’s operation to maintain the desired Set Point. Only boilers set to Auto can be Lead boilers.

Standby Standby boilers can only be activated when all boilers in Auto have been at 100% modulation for a selectable period of time. Standby is generally used when you want a specific boiler to be available in extreme load conditions. Note that a Standby boiler Cannot be a Lead boiler.

Manual The Manual Mode should only be used when testing a boiler. Manual overrides the Prove input. The exact percent of modulation for a boiler can be set with the Manual mode. Once selected, the unit will immediately turn on and modulate to the selected percentage.

Off Any output Boiler A through D not connected to a physical unit should be set to Off. The Off Mode can also be used to disable units that are being serviced.

On The On Mode should only be used when testing a boiler. The On Mode overrides the PROVE input. Once set to On the boiler will immediately start firing and modulate to 100%.

IGNITION %

Adjustable from 1% to 50%	Default: 1%
Button: STAGE/Ignition %

•The Ignition Point is the percent of modulation that must be attained before the unit can be activated.

•For most modern power draft units, the Ignition Point should be set at 1%.

•Older units or atmospheric units may require the modulating fuel valve to be open from 20-50% before proper ignition can be attained. Check with the boiler manufacturer if you are in doubt about the minimum position of the fuel valve for ignition.

------------ STAGE	A ------------
IGNITION	POINT

	1%
[	]
BACK	SAVE

MODULATION START %

Adjustable from 0% to 100%	Default: 75%
Button: STAGE/Mod Start %

•The Modulation Start determines at what modulation percent the previous boiler should be for the current boiler to be activated.

•For example, if the Modulation Start for Boiler B is set to 75%, then when Boiler A reaches 75% modulation plus Ignition%, Boiler B (if Boiler B is in Auto Mode and is not already on) will be brought on at the Ignition % level.

------------STAGEA------------

MODULATIONSTART

75%

[ ]

BACKSAVE

•When modulation is decreasing, the lag unit will remain on at the Ignition % modulation until the previous boiler reaches 40% of lag boiler's Modulation Start, or 2% above the Ignition Point, whichever is higher.

•Using the same example, as the load decreases, Boiler B would modulate down to its Ignition %. Boiler A would then modulate down to 30%. Only then would Boiler B turn off.

•If the Lag Delay is set to anything other than 0, a boiler must always go up to 100% modulation before the next boiler is activated. However, the Modulation Start % should still be set correctly, because it will be valid when modulation is decreasing.

COPY SETTINGS - BOILER A ONLY

Button: STAGE/Copy Settings

•If all the active boilers will have the same Ignition Start Point and Modulation Point, they can be set for Boiler A and then copied to the other boilers.

•It is still required to select the Mode for all other boilers as the Mode is NOT copied.

ALERT

-------- COPY	SETTINGS -------
From	Stage	A
to all	other	stages
BACK		COPY

The Mode MUST be set for each boiler. The Copy Settings command will not set the Mode for the remaining boilers. Only Ignition % and Modulation Start % are copied.

26