My diesel heater has stopped working - was working fine till a bit ago. When switched in - the fan runs, but I don’t hear the fuel pump click when first turned on.
I have 12.5 volts at the main plug - I’ve looked at the schematics in the manual to try and figure out which wire in the main plug should be carrying 12+ volts but I can’t make heads nor tails of the diagrams.
Does anyone know what wires should be carrying 12.5 + .
What should the voltage to the fuel pump be?
Yes, I know there is a diagnostic tool - but rather than spend the $400 plus I think if I can’t troubleshoot it myself it will need to go to the shop.
Thanks,
I ran that exact heater for many years as a live aboard. It’s a good heater but there are some things that wear out over time. I have a very good understanding of how it functions and I also have the diagnostic software on my laptop for them.
That espar will run a startup diagnostic routine. The metering pump won’t start clicking till it passes the startup tests. First on the list of things it looks at is blower speed. If the fan doesn’t get up to rated speed nothing else will happen.
If the blower is ok, it will look at the overheat and temp sensors, and glow plug current. Next thing is it will begin to cycle the metering pump. The pump doesn’t just get the 12 volts to it, it is a pulse output from the controller. It starts at low frequency (slower clicks) until it sees the temperature rise at the combustion chamber sensor. Then it will ramp up the speed of the pump and blower till it reaches its high output (boost). After a time it will ramp down the blower and pump to match the thermostat demand setting.
Without the diagnostic tools it’s hard to say exactly what is malfunctioning, but, in all my years running those heaters, when the heater wouldn’t do anything but run the fan at startup, it was a bad combustion blower.
It’s an expensive part, so I won’t just say to replace it and everything will be ok, but it’s highly suspect.
If you’ve had it for a long time, or don’t know how many hours are on it, I’d say there’s a very good chance it’s bad. When I ran them as a live aboard, I typically had to replace the combustion blower every two years, maybe three. As a side note, espar does not recommend it for live aboard duty for that exact reason.
One more thing to think about, after a number of tries to start it, if it doesn’t fire, it will lock you out. I think you get ten tries or something like that. If you do get locked out you have no choice but to get it reset using one of the diagnostic tools.
I always used genuine espar parts in mine, but I think there might be knock off blowers (cheap imports) if you want to roll the dice.
A genuine espar blower costs more than a complete knock off heater of the same output range.
Good luck with it.
