I have a weil mclain gold boiler (hydronic heat). The boiler cycles on with the thermostat but it does not light. I loosened the bleeder valve to confirm that oil was flowing and it is. This is the first time I started it up for the year. It was working at the end of last year. Anything I can check before I call the service guy? I won't be able to get him here until Monday and its cold. Any help would be appreciated.