Just moved into a house with pool using Pop up heads as cleaners. There are 9 pop ups. 5 are in the floor and 4 are on steps. Heads on steps are labeled Pool Valet which as I understand are made by Paramount. I have only seen the pop ups on the steps come up once and only one or two in the floor work at all. One is up all the time and the other sometimes. None rotate. Where do I start troubleshooting? The control unit is outside the pool cage in a flower bed. If I opened up the control unit what should I look for? Would a regular pool service company handle a problem like this? Thanks !