Wiring

Gary_18

Hi,
Can someone help me with wiring diagram for the below from the condensate heating zone instructions?




Q: How should I control the zone?

A: The simplest way is to use a room thermostat to operate the circulator through a double-pole, single-throw relay such as Honeywell's R845A. You'll also need a single-pole, single-throw, immersion-type aquastat (such as Honeywell's L4006A) to set the maximum boiler temperature when you're not making steam. Wire the controls so the circulator and the burner come on at the same time. The burner will bring the boiler water up to 180 degrees F and no higher. The aquastat sees to that. It will shut the burner off, but the relay will keep the circulator running as long as the room thermostat continues to call. By setting it up this way, you're able to supply hot water to the zone without making steam. As far as the folks upstairs are concerned, the steam system and the hot water zone are totally independent.


THANKS,
GARY

superMARKet

Here's a sample

This is suitable for cold start steam and condensate FHW. On FHW call, the aquastat will maintain 180 degrees, and the circulator will run above 160. The 4081B gives you a circulator limit to avoid pumping cooler water. You wouldn't get that with a 4006A, but if you want to use the 4006, power the circulator from the 845's terminal 4. On a steam call, nothing interrupts the circulator, so pipe wisely to avoid flashover in the hot water portion of the system. The vaporstat, manual-reset pressuretrol, and low water cut-out remain active at all times. You shouldn't build pressure unless there's a call for steam, but the safeties need to be there anyway.