Pool heater only turns on when jet pump is activated

[ps6000]

I have a pool/spa setup with a vs pump and a high speed jet jump. I can get the spa heat to work, but only with the jet pump activated. When I use the pool heat it will again only turn on when the jet pump is active, even if the vs pump is on.

When I say it won’t heat, the heater (Jandy lx400) has no power to it at all. Once I turn on the jet pump it gets power.

Is this how it should work?

 

[1poolman1]

Apparently, someone wired the heater power to the same switch as the jet pump. You don't say whether you have automation. A pool heater can be wired to have power to it continuously, like a VSP, instead of being switched. Then you just turn it on and off when you want to use it. It is best to turn it off abut 5 minutes before turning the filter-pump off and changing the valves from pool to spa position. That cools the heater and allows it to last longer. Never run cold pool water through a heater that has been used to heat a spa. That can cause thermal shock and do damage. If you have automation, cool-down cycles are built into them.

If yo don't have automation, be sure to turn the heater off, or be prepared for a surprise when your fuel bill comes around.

 

[ps6000]

Thanks for the reply.

I do have automation in the form of an older jandy unit.

How would I look at understanding the wiring and switching. I obviously don’t want to damage anything but this is all new to me and I’m trying to learn all of this equipment. I also really want to have the pool heated and can’t help but thing the cost of the jet pump would run up the electrical.

 

[1poolman1]

If your heater is setup for 240v, it can be attached to the same circuit that powers your VSP or its own breaker, but you have to know that first as some can be wired to run on 120v. Its best to hire a pro when working with electricity and that means someone very familiar with pool wiring, not just a regular electrician Even if they say they can do the work, many never have and can cause damage. Miswiring, pool water, and people are not a good mix. If you're lucky, you only damage the equipment.