Going on 24 years old and has intermittently always given me grief. Seems like a couple times a year it just quits.
Often if I shut off the breaker for 5 or 10 minutes and back on, it will work fine for another 6 months.
Today, we're in the middle of TS Irene. Did some work inside and relieved that the power did not go out.
Get in the shower and no hot water. Great!!!!
Open up the boiler and the purge light is flashing.
I shut it off for a minute and back on. The blower (I think) starts immediately, but then shuts off after a few seconds, then nothing.
I shut it off for a few minutes this time. Turn on the breaker and the power light goes on and does nothing.
I tap the control module (ok I hit it hard) and wiggled the wires a little and it purged, ignited, and the valve light goes on as norm. Now seems to be fine.
Any ideas to try?
A little electrical spray in the connectors or maybe just replace the control board and hope?
There are numerous safety interlocks and any one of those or the control board that they feed could be intermittent or failing. It is really hard to say without some proper diagnostics. It can get quite expensive shooting in the dark. The best place to start is with the theory of operation and trouble-shooting charts in the manual.
Depending on what else is going on, how well things were maintained, and the state of the house after 24-years (additions, insulation, windows, doors, etc.), it may be quite an efficiency increase to start to consider replacement. While some of the rebates and tax credits no longer apply, it really depends on where you live - some utility companies still have some really good, generous ones. An intermittent heating system is a disaster waiting to happen, especially if the house is vacant at all during the coming winter months.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013