Trilogy Spas

If you have the flashing temp of doom. This means your high heat limit was triggered. Causes are either stuck flow sensor in the on position. Plastic clear fitting w two wires going to it. If you turn tub off. Use a multimeter or voltmeter and w tub off test across those two connectors. Should be open circuit w tub off. If this reads connection or continuity it is bad. Diagnosed mine and replaced. Works good as new. If this doesn't turn out to be your issue. Could be bad heater relay or bad circ pump overheating and shutting off till it cools off. Hope this helps