I am researching possible solutions to the inevitable cooling of the bath water as it runs through the pump and jets. I have looked at tankless water heaters and inline water heaters but would like your input. Can an inline heater really keep the water hot, without refilling the tub?

Thanks,

Colleen

Oh and I would like to be able to put the heater between the tub, pump and jets and not as part of the waterline coming in from the faucet.

THanks,
Colleen

Yes, an inline heater will actually keep the water hot very nicely. You just need to make sure to get the right heater. Your best bet will be to get a heater that is made for your make and model of tub. This will make connecting easier, and will also size heater correctly for size of tub. Please let me know if this helps. Most newer tubs have a kit you can buy making install and overall function very nice.

Just one note, these inline heaters are only good for keeping the water hot, not heating cold water. If you don't have enough hot water from house water heater to fill the tub with hot water, the inline heater will not work for heating the cool water in the tub. They are strictly for keeping the water that's already in the tub up to temp.

Some spa tubs have a built in heater that keeps the water hot and can actually raise the temp, many do not. I would think it's possible to rig and inline heater with your spa recirculation lines but I have not seen an add-on accessory like that. Did you spa once heat the water and no longer does that? I don't know for sure but contacting a spa manifacturer would be your best bet.

As said above, install In-Line heater. This heater will not raise water temperature already in the tub - but will keep it at about the same as it was delivered to the tub. Lowe's sells them via Special Order. These heaters are easy to install since they mount on to existing tub PVC plumbing with 2 hand tight unions