Espar Hydronic 4 problems

[forbin]

Hey, new to this forum but there seem to be more posts here about diesel heaters than on the typical places I look (cruisers forum, sailboat owners, etc) so I thought it was time to join!

My heater has not started the last three times I've tried to run it. It goes through the start sequence (blowers on, I can hear the fuel pump working) but after a few minutes it shuts down (the light indicating that it is running stays on the thermostat) and then retries a few minutes later. The unit was serviced about 18 months ago and cleaned out and a new glow pin was installed at that time. It's probably been run for a total of 40 hours since the service (I don't have a diagnostic tool.)

Last time it had a similar was around six months ago because the plastic overflow tank fitting cracked and leaked all the coolant out of the tank. I had a proper expansion tank installed and the installer bled the system and it worked again without issue for a few months.

Last week was when the problems started again. I found a small leak on the coolant out line from the heater (right at the heater) so I will fix that but there is plenty of coolant in the tank. I'm going to try to bleed it tonight just in case any air got in to the system and see if I can get it to start.

Does anyone have any other ideas? Or if you happen to be in the Seattle area do you have one of the diagnostic tools or know anyone that does and would be willing to let me borrow it??? I really want to be able to fix this myself instead of paying the $100/hr every time there is an issue...this heater is getting expensive!

Thanks, Brian
http://svaquavit.tumblr.com

 

[vyv_cox]

I don't know your unit but one of the first remedies to try with similar problems is that the power supply is correct. My air blown unit behaved in a similar way until I realised that with the battery charger running it worked perfectly.

 

[forbin]

vyv_cox - thanks for the info!

I was able to get the heater to start on the third try on Wednesday, after which I ran it for 90 minutes with no issues. I tightened all the host clamps and then bled the heater (I can't tell if there was any air) but there was plenty of coolant in the tank to begin with so I'm not sure that had anything to do with it, but it did stop the coolant leak. The first two start attempts were 3 minutes apiece and each resulted in the fuel pump running, the water pump starting, and hot exhaust (though it wasn't the cleanest looking exhaust) so I think the voltage is ok.......but......it was plugged in and had been on shore power for a while so there is still that possibility. The timing of the start cycles makes me think it could be getting clogged or the flame sensor isn't working right (or is clogged.)

The exhaust was fairly 'dirty' so it could be getting coked up, possibly because the shutdown/purge cycle doesn't seem to be running (like the power gets cut to it by the thermostat) but I haven't been able to trace all the wiring yet. I may try to run some kerosene though it but I need to find out what the diesel is at our marina first...I'm assuming it's ULSD but it's red so I want to ask to make sure.

Anyway, progress I think...at least I'm learning a lot about it.