In this commercial building I had two Lochinvar heating boilers that operated in as a lead lag set up. They had been in place for a few years. Time came to do the seasonal start up. Could not get the second boiler to operate when the first boiler was running, no matter which boiler was first boiler started, Low gas pressure was tripping of the second boiler. Hmmmm
Called the gas supplier to check out the gas meter.
The mechanic and I were with the tech from the gas supply company. We removed the meter to see if the meter was defective as the previous few months all new meters were installed on the street.
When we removed the meter, we found a large ball of crunched up paper that I guess the remover of the old meter put in there to keep out garbage or what ever. The crunched up paper allowed enough gas through to operate one boiler but not enough volume to operate both.
Red face moment for the gas company.
Removed the ball of paper and both boilers ran fine.