Component identification, possibly 'transformer switch'

[preston8]

I am in the process of reverse engineering an electrical control box for a spa heater, and have stumbled upon a component that I have not encountered before.

There are two of these components in the system. I was not able to find any information from the part numbers. The coil leads me to believe that this is a transformer. The additional nodes on the sides and the position within the system also lends to a type of switch. Is there such thing as a transformer switch?

 

[berkeman]

Might be relays (contactors) for the pump and the heater element...?

 

[jim hardy]

Search engines are your friends.

I'd wager it's a "Hartland Controls series HCC contactor"
http://www.hartland-controls.com/#!products/c194u
http://www.hartland-controls.com/#!about3/cq5o
part number breakdown here
http://www.hartland-controls.com/#!nomenclature/c14s4

 

[preston8]

Indeed it appears to be a "contactor". I understand what role they play in this system now, thank you.