I installed a ritetemp 8082c programmable thermostat and in order to use the remote I need to connect a 24 v power supply. I have run an additional wire but am unsure where to connect it at the furnace to get the 24 volts. The thermostat works properly with the red (rh) and white wires connected but without the "c" wire connected the remote does not work.
I have a 4 zone hwbb oil boiler setup. I have tried connecting to each of the 3 terminals on the zone valve (taco) with no luck.:confused:

The common (C) terminal on the thermostat must be connected to the opposite leg of the low voltage transformer from the red. In other words, trace the red back to one of the low voltage terminals of the transformer and connect the C to the other (low voltage!) terminal or lead.