878. Support: New heater assembly installed on old Controller, but spa still does not heat.

You reported that you have installed a new heater on your original spa controller, but the spa still don't heat. The problem can be that the pump is not running, or the pump is running but without strong water flow out of the jets. The problem can also be the new heater is bad, or the controller is not supplying power to the heater: - Improper installation of the heater may cause it to go bad. Loose connections or a crack on the heater terminals will affect the heater's performance. Water can leak through and come in contact with power on the heater terminals. This will trip the GFCI. - Whenever installing a new heater, always start with fresh new water. The old water may be what caused the original heater to go bad. Even a one day old water that is not treated goes bad. - It may be possible that your spa controller is not supplying the correct power to the heater terminals. When a 220V system is calling for heat, 220V should be supplied to the heater terminals. (110V to the heater terminals if only 110V is supplied to the spa). When taking voltage measurements between the two heater terminals, the voltmeter should display 220V+ (for 220V units). If low voltage is detected between the two heater terminals, the problem is NOT the heater. - You can also try to measure the resistance off the heater terminals. A good reading should be a stable reading between 9.8 ohms to 11.8 ohms. NOTE: If your original heater is rated anything less that 5.5KW, then you have installed the wrong size heater. There may be low water flow that caused the heater to burn out or to go bad. Burnt heaters due to mis-installation are not covered under warranty. EXAMPLE: If your original heater is rated 4KW or lower and you installed a 5.5KW heater, that would the problem. A 5.5KW heater requires stronger water flow than a lower wattage heater. The pump needs to output at least 25 GPM through the heater housing for a 5.5KW heater. If you find that the heater going out is not an installation problem and not the controller problem, contact us for an RMA to authorize the return of the heater for a warranty evaluation. But if you find out that the Controller is not supplying power to the heater terminals, then there is possibly something wrong with the heater circuit within the spa controller. (May also Attach KBID 72 if customer has an old controller to try and get a controller sale)