Bradford-White Corp BJVS Operating Instructions, Grounding, Auxiliary Devices, Normal Operation

Brute Mini Hydronic Boiler Page 21

6.3 Grounding

WARNING

The boiler must be electrically grounded in accordance with the requirements of the authority having jurisdiction or, in the absence of such requirements, with the latest edition of the National Electrical Code, ANSI/NFPA 70, in the U.S. and with latest edition of CSA C22.1 Canadian Electrical Code, Part 1, in Canada. Do not rely on the gas or water piping to ground the metal parts of the boiler. Plastic pipe or dielectric unions may isolate the boiler electrically. Service and maintenance personnel who work on or around the boiler may be standing on wet floors and could be electrocuted by an ungrounded boiler.

AVERTISSEMENT

La chaudière doit être mise à la terre selon les exigences officielles locales ou, en l’absence de toute instruction officelle, l’installation doit être conforme au National Electrical Code, ANSI/NFPA 70, aux États-Unis et avec la dernière édition du Code électrique canadien CSA C22.1, Partie 1, au Canada. N’utilisez pas la tuyauterie de gaz ou d’eau pour mettre à la terre les parties métalliques de la chaudière. Les unions diélectriques ou avec tuyau en plastique peuvent isoler la chaudière électriquement. Les membres du personnel de service et d’entretien qui travaillent sur et autour de la chaudiére peuvent marcher dur des planchers mouillés et pourraient se faire électrocuter par une chaudière non mise à la terre.

6.4 Auxiliary Devices

6.4.1 Flow Switch

SECTION 7.

Operating Instructions

7.1 Normal Operation

The Brute Mini BJVS and BJVT boilers are capable of automatic operation based on a call for heat at present temperatures. The boiler has an internal safety system which allows operation in a variety of conditions and prevents operation when certain adverse conditions are encountered.

When the wall thermostat calls for heat and the boiler is powered, an operating cycle is initiated. (On continuous pilot ignition models (BJVT) the pilot must also be lit). The pump relay turns on the pump, the damper activator rotates the damper blade to the open position and the indicator light comes on.

On spark ignition models (BJVS 50-75), if the water temperature is below the limit setting, the ignition module lights the pilot and checks the flame existence. After the pilot is proven to be lit, the ignition module opens the main gas valve and the main burners ignite.

On 2-Stage spark ignition models (BJVS 100- 225), if the water temperature is below the limit setting, the ignition module lights the pilot and checks the flame existence. After the pilot is proven to be lit, the ignition module opens the main gas valve and the main burners ignite. The main gas valve is controlled by the two-stage operating control (see Figure 11) and will cycle between high, low and off as the load demands.

			BREAKS R-B
			MAKES R-W
	LEFT SWITCH		ON RISE
TEMPERATURE	DIFFERENTIAL
RISE		2	BREAKS R-W
			MAKES R-B
			ON FALL

If the system includes a flow switch, it should be wired in series with the high-limit switch. The boiler will not fire unless the pump is running and the flow switch is closed.

Field installed safety devices and operating

controllers, such as a valve end switch, draft switches, relays, timers, and outdoor temperature reset devices, can be connected to the boiler through the wall thermostat circuit. Do not exceed a draw of 30VA on the transformer secondary.

BOILER INLET

SETPOINT

(ADJUSTABLE, FACTORY SET AT 140°F)

LOW

FIREINTERSTAGE DIFFERENTIAL

1

BREAKS R-B

MAKES R-W

RIGHT SWITCH ON RISE DIFFERENTIAL

2BREAKS R-W MAKES R-B ON FALL

HIGH

FIRE

6.4.2 Heat Anticipator

For single zone installations, the wall thermostat heat anticipator should be set at 0.5 amperes. For multi-zone installations, have a qualified electrical technician make the necessary measurements to properly set the thermostats.

DIFFERENCE BETWEEN THE TEMPERATURES AT WHICH THE

1TWO SWITCHES MAKE R-W. FACTORY SET AT 10°F (6.6°C)

TWO SPDT SWITCHES OPERATE IN SEQUENCE. EACH

2SWITCH DIFFERENTIAL AT APPROXIMATELY 3°F (1.7°C)

Figure 11. L6008G Operation.