just installed another PB 105 and customer has a 24volt zone valve for the dump zone. since the boiler supplies 120volts when it overheats is there any reason why I cant just put a Taco transformer in that circut to power up the valve. I did it...made it overheat to check it....it worked...BUT now the customer says the dump zone is open all the time now. He disconnected it and is waiting for me to return. is there a wireing problem ...thoughts???