Welcome to Just Answer, I'll do my best to help with your situation. First I need some info; what is the brand and model of your relay? how many zones do you currently have on your heating system? how are they (the zones) controlled? zone valves or a circulator for each zone?
I assume you have the install instructions for the relay in case you need it. All the following numbered/letter terminals mentioned are on your relay (unless stated otherwise). First you run a 120 volt feed to N (neutral) & H (hot) on the relay. If the jumper is installed to 3 leave it in place. Then connect the hot side feed of the circ to 4 N/O and the circ neutral to the neutral feed. Next the control side, you wire the flow switch and the aquastat in series to T & T. Then connect 2 leads from 6 N/O & 5 to T & T on the boiler control.Wiring it this way will make the heating system circ run when the pool heater calls. Since the zone valves should be closed no heat should circulate through the house. This is not ideal but will work. The best way to do this is with another relay which would control the heating circ instead of having the boiler control the heating circ. But you only have one relay for now. If you don't want the heating circ to run you can disconnect it until you get another relay.