3 flashes, won't ignite. Natural gas is on and good pressure through line. Manual says that pressure switch malfunction of some sort. Any ideas what to do?
I have never used heater as it was installed new in the shop that I just purchased so I do not know how much it has been used.
Heating & Cooling - Mr. Heater - MHU45NG
Answers & Comments
Check the setting of the control valve and make sure it is not set up for LP gas. Check the pressure switch with a meter and make sure the NO and NC connections read correctly.