Espar Heater with unreliable ignition

[greganddrew]

We have an Espar (Eberspacher) D 7L TD diesel heater on our 1984 CHB 47 which works perfectly well when turned on and keeps us warm all day. The only problem is that the ignition is unreliable. It seems to engage only after a long period of inactivity. If I turn it on today and turn it off tonight, I can be sure that tomorrow it will NOT turn on…… weird…??? After a few weeks have passed (sometimes more), I will be able to turn it on as though nothing was wrong. Is anyone familiar with this phenomenon? I have replaced several wires and parts, including a new glow plug and the control box (part #30 in the manual). The heat is wonderful as it vents throughout the boat… If you think you can be of help in this situation, your input will be appreciated. Thanks.

 

[koliver]

Mine misbehaved the whole time I had it. It seemed to need the fuel to be warm before it would start easily. Others have tried feeding theirs with Kerosene.

 

[magna 6882]

I dont know much about all the models but on mine i was having trouble and i discovered the thermostat would give trouble codes but the real problem was the heaters were showing several thousand hours of use when this just couldnt be. I reset to zero and have not had any problems since.

 

[tiltrider1]

Call Scan Marine in Seattle. They should be able to help you.

 

[Steppe]

Scan Marine in Seattle is the dealer for Wallas heaters. Sure Marine in Seattle is a dealer of Webasto and used to rep Espar but the Espars are no longer featured on their website. Either company should be able to advise on alternative heat systems.

 

[Portage_Bay]

AMC Cliffv's Marine https://www.nwmarineair.com/ is an Espar dealer.

 

[Lepke]

Sounds like a fuel metering problem. The metering pump creates bubbles and the fuel line needs to run up to the heater. The pump needs to be installed so it is 15° or more to vertical. See pic.
On Youtube John McK 47 has a series of videos on Chinese heaters that are a copy of Espar and others.
Watch:

 

[Bmarler]

Without properly diagnosing it you can throw money at it for quite some time till you get the right fix.
Years ago I bought the serial interface and software so I could look into the control boxes and see what’s actually going on. If there’s someone in your area that services espar it would really speed things up.
The fuel pump mounting has been mentioned, and should be checked, and I wonder about the supply side of the pump. If there’s a lot of air in the line you should be able to see it. If the supply to the pump is suspect, run a temporary line from a fuel can to it.
Whatever you do, don’t just try to keep restarting it. If it fails too many times, it will lock you out and must be reset using software or other diagnostic tool.
Espars have a little startup sequence they do, you can sit by it and watch and listen. It should do two attempts to start if everything is ok except for lack of fuel.
If it only kicks the fan on momentarily, then stops, it’s something else. I wonder about the overheat sensor. When the heater shuts down, residual heat could be causing it to trip.
The combustion blower motor is also a suspect. If the heater has a lot of hours on it there could be a lot of carbon dust floating around in there. Those aren’t user serviceable, they should only be replaced. It’s impossible to set the proper clearance on the blower wheel without the equipment to measure the fan performance.
But if it gets to the part where the fuel pump starts pulsing, but still doesn’t start, it’s probably a fuel problem.
Those big air heaters are really nice, and generally very reliable. Once you get it figured out it should be a good unit for you.

 

[Marco Flamingo]

Mine developed a software glitch that would not allow a restart unless the main circuit breaker to the heater/thermostat was turned off and back on. The circuit board was no longer available (but I did see the price list of part$ I would need in the future). After using it that way for awhile I decided to sell it for parts and use some of the proceeds for a Chinese heater. That was the fix for me.

 

[greganddrew]

Thanks everybody for your well thought out responses. I've learned quite a bit and will see what the best options are... Take care.

 

[mike r smith]

My 1980 Trawler yacht has an 8000w Eberspacher diesel heater, which I believe is original. Not been serviced since 1999.
It was sometimes tripping out on start-up and thereafter refusing to operate. It runs off the engine batteries. When underway it works fine.
Our local agent explained that the early models are voltage sensitive. We found that if the batteries fell just a little below 12v, it would not operate. Keeping the batteries above 12v - no problems.

 

[H2O_Doc]

Another troubleshooting idea....

My Espar D2 was finicky to start, but once running, it'd go forever. I was very frustrated and ready to buy a new one. Turned out, it was a splice in the wire, so it got low(ish) voltage when it pulled a lot of power for the glow plug at startup. I eliminated that splice, and now it's reliable as ever.

Your thermostat should have a way to read codes, right?

 

[greganddrew]

Thank you everyone. I think @MikeRSmith nailed it with the "voltage sensitivity" on the original models. We'll probably replace this with a newer smaller model.

 

[Bmarler]

Thank you everyone. I think @MikeRSmith nailed it with the "voltage sensitivity" on the original models. We'll probably replace this with a newer smaller model.

The d7 is a fantastic heater, don’t just toss it if you decide to replace it. There’s a business called foenix marine services that works on the d7 and d12 on an exchange basis. Since some parts of those are not available new any more, he looks for good used ones he can test out and keep those heaters going.
If low voltage is keeping it from firing up, I’d fix the voltage problem. All espar heaters will have a voltage sensor and won’t fire up when the voltage is low.