We have a 24,000 SWG pool - natural gas heater, in Houston, Texas area- lost power for a few days, opened the pump to back drain the filter, and pipes, turned of breakers to pool and heater, then covered the pumps, filter and pipes. Power is now back on, pool is running, freeze protection mode (automatically programed) air at 35, water at 42, in spa mode - freeze protect, but heater is not coming on... has bo code, how do we check the heater? Appears to be NO leaks - Thank God! Husband is going to take a hair dryer to the gas regulator