Dear Mr. Winters:
Thank you for writing to us. You need a good electrician to look it over. All heat pumps are 208 / 240 volts, single phase 60 hertz in the USA that are used on residential homes. Some commercial installations use 3 phase and higher voltages. I am not a big step down transformer fan. I would rather see a dedicated 208 / 240 line for your heat pump. They run 3 wires. 2 hot wires and a ground. And then they run another bonding wire to the equipment. Maybe it won't be so hard for the electrician to run a bigger wire if your old wire is in a conduit underground. Then they just attach the new wire to the old wire and when they pull the old wire out it pulls the new wire in. A fast job if the conduit is big enough. Then you get a breaker panel and you can have your 110 volt equipment and your 220 volt heat pump. Maybe your wire is not run in a conduit? That will be harder and somebody will have to dig I guess. Some Chlorinators and pumps can use 220 volts. They will say on them if this is possible. On the smaller HP pumps that come with 18 foot pools though I doubt that it can be done though. Whatever you have to do make sure a licensed electriction does it as that is what all the manufacturers want to see and they can void a heat pump warranty if they find out other wise. Also get 2 or 3 quotes. Lately I have seen the exact same job be quoted at $225.00 and $1850.00. Some electricians seem to be more proud of their work than others I think.