Burnham V7 SERIES manual Tankless Heater Data Rear

TABLE 3: TANKLESS HEATER DATA: Rear

Mounted Heater on Steam and Water

Boilers

		Heater Rating		Pressure Drop
Boiler	Heater			thru Heater
		(GPM)
				(PSI)
Model	No.
		Steam	Water	Steam	Water
V713	V1-2	---	3.25	---	5.6
V73	V1-2	2.75	3	3.9	4.7
V714	V1-1	---	3.5	---	4.4
	V1-2	---	4	---	8
V74	V1-2	3	3.25	4.7	5.6
V75	V1-2	3.25	3.5	5.6	6.4
V76	V1-2	3.75	3.75	7.2	7.2
V77	V1-2	3.75	4	7.2	8
V78	V1-2	4	4.5	8	9.8
V79	V1-2	4	4.5	8	9.8

TABLE 3A: TANKLESS HEATER DATA: Front Mounted Heater on Water Boilers

Boiler	Heater	Heater Rating	Pressure Drop
Model	No.	(GPM)	Thru Heater (PSI)
V73	222	3	22
V74	222	3.5	22
V75	222	4	30.5
V76	222	4.5	33
V77	222	4.6	33
	A54	5.5	36
V78	222	4.75	40
	A54	6	39.5
V79	222	4.75	40
	A54	6	39.5

cold water with the hot. This prevents excessive and possibly scalding hot water at the fixtures. In addition, savings of hot water will be achieved since the user will not waste as much hot water while seeking water temperature to his liking. Higher temperature hot water required by dishwashers and automatic washers is possible by piping the hot water from the heater prior to entering the mixing valve. The mixing valve should be “trapped” by installing it below the cold water inlet to heater to prevent lime formation in the valve.

WARNING

Install an automatic mixing valve at the tankless heater outlet to avoid risk of burns or scalding due to excessively hot water at the fixtures. Adjust and maintain the mixing valve in accordance with the manufacturer's instructions.

3.FLUSHING OF HEATER — All water contains some sediment which settles on the inside of the coil. Consequently, the heater should be periodically backwashed. This is accomplished by installing hose bibs as illustrated and allowing water at city pressure to run into hose bib A, through the heater, and out hose bib B until the discharge is clear. The tees in which the hose bibs are located should be the same size as heater connections to minimize pressure drop.

4.HARD WATER — A water analysis is necessary to determine the hardness of your potable water. This is applicable to some city water and particularly to well water. An appropriate water softener should be installed based on the analysis and dealer’s recommendation. This is not only beneficial to the tankless heater but to piping and fixtures plus the many other benefits derived from soft water.

NOTE: STEAM BOILERS

a.During summertime operation, the normal water line should be raised 1”, from 22-5/8” to

23-5/8” (see Figure 1C) for improved tankless heater performance.

G.INSTALL SMOKEPIPE — The V7 should be vented into a fireclay tile-lined masonry chimney or chimney constructed from type L vent or a factory built chimney that complies with the type HT requirements of UL103. The chimney and vent pipe shall have a sufficient draft at all times, to assure safe proper operation of the boiler. See Figure 13 for recommended installation.

1.Install a draft regulator (supplied with boiler) following the instructions furnished with the regulator. See Figure 14 for alternate draft regulator locations.

2.Consider the chimney overall. Chimneys that have

ahigh heat loss may become less suitable as the heat loss of the home goes down and the efficiency of the boiler installed goes up. Most homes have a chimney appropriate for the fuel and the era in which the home was built. That may have been a coal fired or an inefficient oil fired boiler built into

ahome without insulation or storm windows. With increasing fuel prices that home probably has been insulated and fitted with storm windows so that the heat loss of the home has been reduced. This

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