Lifebreath 4TONDHW(T) Expansion Tanks, cold, Anti-ScaldValve, Off Season Circulation Controls

Expansion Tanks

Expansion tanks are only required for “Closed Systems”. The expansion tank has an air bladder, which will contract to relieve pressure in the system. Pressure is created in the closed system when water is heated in the water heater. Expansion tanks should always be connected to the cold water piping between the water heater shut off valve and the cold water inlet to the water heater. Follow manufacturers instructions for sizing and installation.

cold	hot
	water
	air cushion
EXPANSION TANKS

Anti-Scald Valve

An anti-scald valve is required when the water heater thermostat is set above 140˚F (60˚C). Also, an anti-scald valve may be required for all installations by the “authority having jurisdiction”. The valve is placed in the hot water supply piping from the water heater downstream of the heating loop connection and upstream of any domestic hot water connection.

The purpose of the valve is to limit the maximum temperature available for domestic hot water by mixing hot water from the water heater with cold water from the municipal supply.

The Anti-Scald valve must be thermostatically controlled and approved to the ASSE standard No. 1016 and 1017 for use as an anti-scald device.

Note: There are a number of pressure balancing valves and mixing valves on the market which are not certified as a anti-scalding device.

Time to Scald (1st degree burns)

Temperature	Time
120˚F	8 min.
130˚F	20 sec.
140˚F	3 sec.
160˚F	<1 sec.

Off Season Circulation Controls

(Models with a ‘T’ in the model number)

Although the UCG (Unified Canadian Guideline) does not require these controls, a few building codes and municipal by-laws do. They are used to provide periodic circulation of water through the space heating loop during the summer and other periods of infrequent use. The concern is that water which remains stationary in the heating loop during the summer may be less than desirable as domestic hot water when it is returned to the water heater at system startup in the fall.

Thermostats

There are two thermostats controlling every combo system, the water heater thermostat controlling the hot water temperature and the room thermostat controlling the room air temperature.

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