I live in Florida and have a typical mar cite in ground 15’ x 30’ pool with a spa. I have 2 water pumps: one 50lb pressure spa pump that just has a circuit from pump to spa and returning water back to spa pump for 6 jets and to heat spa. The other pump is a typical 1hp 5lb pressure pool pump that has a separate closed circuit to 3 pool outlets for circulation and back to pool pump using an in line salt water system. This closed circuit does NOT utilize the Electric Pool Heater that the SPA circuit does.
So we have 2 separate water flow circuits: one for heating the Spa and one for circulating the pool and Spa with NO heater connected with pvc pipe.
I had asked the pool builder to use the electric heat pump to heat Both pool and Spa but he said most people just want the SPA heated only in Florida. Needles to say I was pissed.
Now here is the technical question I have. Would it be possible to utilize a 2way plastic connecter from the Heater outlet to SPA connected to the Heat pump and plumb in a 1.5 " pvc pipe straight to the Pool Return to Spa pvc pipe? I could have the heater side outlet open to Both SPA and Pool or just to Pool or neither and just have original Pool pump circuit used leaving Spa to Spa heated circuit closed altogether?
The reason I hesitate to make this connection is that if I connect the Spa only circuit to the Pool to Pool and Spa circuit, the water pressure may be compromised and there wont be enough circulation.
I know you will be asking about all these variables but I must know if making a simple bypass connection between Spa circuit to Pool circuit to utilize the heat pump to heat either or both circuits will work because all the pipe are under pressure and using one or the other or both will compromise the flow to either circuits.