Ran a service call with the boss the other day and not sure if he handled it the correct way and if I am ever in the same situation want to do it right.
The call was for no heat. The lady had yhe system cut off so we jumped it out under the house. Everything worked fine so we determined the problem to be with the T'stat.
The boss made second trip out to check out t'stat but found it to working as well. A day goes by the lady calls back and said it worked for a day and then quit working.
Boss makes third trip out, jumps out system due to the lady not being at home and cutting system off, everything works fine again.
He seems tho think maybe the moduleboard is shorting out and locking out so he changes it. Its a whiterogers 50A50 with some other numbers, can't remember them all.
Works for two days and then goes into a lockout again. Boss thinks the pressure switch diaphram may have a crack in it so he changes it. Works for a day and then locksout again.
By now the lady is getting frustrated and so is he. This time he is going out of town and asked me to go by and see if I can find anything he might have missed. If he is jumping it out and its firing up, what could he have missed I was wondering. Anyway I wanted a try at this problem.
When I arrived, went under the house put the jumpers on : inducer draft motor starts, ignitor warms up, no fire. Checking voltage, 24 volts is sent to the gas valve but it did not open, retried system and upon 24 volts to the valve, I bumped the valve with a nut driver and it opens up and then shuts back down.
Changed the valve and now the system is working fine. My question is I know that problems have to happens when we're there but what do you do when there is a problem but not when your there?