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HELP with Espar heaters

Hi Brian, I understand you are the expert on these heaters and I could use some help. I have an Espar/Airtronic D2 heater in my boat. I seem to be having the opposite issue from most folks, mine won't shut down. I can manually turn the heater on and it cycles and fires up no problem but the temperature settings don't seem to work. I wasn't able to find much information on where the temperature sensor would be so presumed it was in the thermostat/control unit. The local boatyard in Nanaimo thought the same so they replaced the control unit but the issue is still the same. It fires up, heats up but won't turn itself off again. Where is the temperature sensor located? How do I check it for correct operation? Thanks. Henry
 
Interesting, mine is doing the same thing, but not 100% of the time, only about 70%. Sometimes it works fine, cycles on and off dependant on the temp dial, but other times it just runs full speed non-stop. I have checked wiring for anything obvious, but I don't see anything.
 
Brian
Thanks for the time you put into this forum, it has been a big help to me.
My heater is a D5LC, installed around 2002 to replace a D3.

2 years ago it would not start, gave an overheat code.

Thanks to your information and suggestions to others I was able to unlock the heater, but it gave an immediate overheat code as soon as it was turned on.

I pulled the PCB and resoldered the appropriate pin, no change.

I installed a new PCB, no change.

I tested a new overheat switch and it showed continuity and the old switch showed open, so I installed the new one. The heater worked fine with either PCB.

After 2 seasons the heater shut down with an overheat code.

I reset it, it ran for about 10 minutes and shut down with an overheat code.

I removed inlet and outlet ducting, reset it, and it ran for about 10 minutes and shut down with an overheat code.

Changed the PCB with the old one, same 10-minute run time.

Brought it home, ran the PCB tests per the TS manual, and it tests OK.

Heated up the overheat sensor (that was replaced 2 seasons ago.) It is labeled 170 C but consistently opens around 100 C.

I ordered a new one and will compare its opening point, but it looks like I've had one overheat sensor fail and replaced it with another bad one.

Thanks.
Don
 
Wow! In 17 years I have never had to replace one. Usually pc bd. If the new one does the same thing, it might be time to check the air temp coming out of the heater. It should be about 255 F. Six inches down the duct. I have a probe sensor I poke into the ducting. Also it might be time to remove the blower and plate between blower and combustion chamber. Check that the burner has not had an aneurysm. Blowing flame out of the burner tube. Rare but has happened a few times. Generally the heater would run badly in that case. If you do take it apart you need a new gasket for the plate and a new seal to go between the burner tube end and the plate. The green gasket will completely fall apart when disassembled. Let me know what happens
 
Regarding the overheating D5LC:
Got the new overheat switch, it tested same temp range as older one.
Installed the heater, overheat tripped in 7 minutes.
Stuck a multimeter probe in the duct, it showed 190 when the overheat tripped.
What do you think of the new Airtronic 5 L?
 
Ocean40 said:
Regarding the overheating D5LC:
Got the new overheat switch, it tested same temp range as older one.
Installed the heater, overheat tripped in 7 minutes.
Stuck a multimeter probe in the duct, it showed 190 when the overheat tripped.
What do you think of the new Airtronic 5 L?
Click to expand...
First. I would be double checking the pc board. If you are sure the solders are good, I would then assume that the ecu- control box is defunct. Too expensive. $700 to invest in an old heater with old blower. Again. The flame tube would be good to look at.*
The d5a is very similar, but has a new ecu, inside it. They have been very reliable. The heat exchanger is almost exactly the same, as is the glow plug and atomizing screen. The motor is new, and in most cases has been very reliable. The overheat /flame sensors are extremely reliable. The old flame sensors on the d5l are not. Overall very good. Early models had carboning issues. But that was a software issue. The latest ones made after the first couple of years have been fine. They are not fond of running on low for extended periods of time, but normal use would have them alternating between the three speeds. If you leave the heater on at very low settings to keep a boat warm, but not room temperature as in at the dock unoccupied will have the heater possibly running on low for days on end. Premature carboning if the screen and glow plug can result. They are not meant for this use. Nor was the old d5l. Live aboard use as the only source of heat will, like the old d5 wear out the blower due to the high hours. The new blowers are rated for around 5000 hours. Some have come into me with 7500. There is the odd premature failure, but these have been rare. I have installed probably about 50 of them myself, and am the service person for most of them. Overall very good. They have three speeds instead of two, and move between those seamlessly, not sudden steps like the d5l. So more even temperatures
 
Hi Brian,
My D12 has kept going for many years, with your help a couple of times! Now I have an issue unsolved and the weather is chilly.
Heater stopped running after having worked fine.
Resetting by the termostat, at first the blower run a few seconds then stopped. Now resetting the termostat only cause a short, maybe 1 sec starting attempt.
I checked the power feed and 27, 2 V is reaching the ECU unit.
My feel is that some safety cirkuit prevent the unit from starting but I cannot find out how to identify the source of the problem.
The blower run normally as should in ventilation mode.
The starting attempt is so short that the fuel pump does not start up. The pump is new, just two years and I have replaced both the small filter on the pump an a primary inline filter for this season.
Great if you have some wicedom to share!
Cheers from Old City Marina in Tallinn, Estonia
Stefan
 
Check the voltage at the ecu as you turn it on and see if it drops drastically. I think it is around 20 volts that it won't go. If that is ok. Unplug the 6 pin white thermostat plug at the heater and jump red to yellow. This will tell the furnace to start bypassing the switches. If it goes then the rotary dial or thermostat are the issue. If still no go then you could take a close look at the connections at the ecu, or open it up and emery cloth clean the contacts of the three relays inside.let me know
 
silk;504978]Check the voltage at the ecu as you turn it on and see if wasok)drops drastically. I think it is around 20 volts that it won't go. If that is ok. Unplug the 6 pin white thermostat plug at the heater and jump red to yellow. This will tell the furnace to start bypassing the switches. If it goes then the rotary dial or thermostat are the issue. If still no go then you could take a close look at the connections at the ecu, or open it up and emery cloth clean the contacts of the three relays inside.let me know[/QUOTE]

Hi Brian,
Voltage is ok and I can find no loose connections.
Can you propose jumping referring to the numbers on the 6 pin plug. I have other colors on the cables than you write
On the furnace plug I have 1 white, 2 red, 3 brown, 4 brownx2, 5 grey, 6 blue.
Nr 2 red, is positive and connection with any other five plugs cause the fuse to blow (I tried all possible jumps)

Can you advice how to test if the termal breaker on the furnace is ok. It is built in and hard to reach unless I take out the whole unit. To do this I need to remove SB silencer and exhaust hose involving a lot of hrs.

I opened both the ecu box and the pulse generator (where I found a glass fuse that was ok).
The contacts looks ok on the relays. I slightly cleaned one of them that had a little soot on it.
After putting them back the unit made a slightly longer starting attempt, maybe 3 seconds. But after this one time attempt it is back to just a one second, or so, cough from the blower motor when power is connected. In blower mode the fan run normally. Maybe the ecu unit is bad. The soldering on the electronic card did not look nice but neither burned. If you allow I can send some pics. PS and if you wish to limit your sharing of visdom to your nearby business area, just say!
Cheers from Helsinki this time,
Stefan
 
Good day , sorry for the delay. I was very busy at work and then I went on holidays.

It should be red to blue to start it at that 6 pin plug . Blue should gom to #7 or #8 in the two pin middle plug on the bottom of the ECU. That is the start wire
 
Hi Brian,
I bought a new CPU on ebay from a guy in Germany. I just arrived on the boat and installed it.
The heater fired up on the spot so main prob fixed.
One prob is remaining and tha is tha when running on full power the thermal breaker trip after a few
minutes. On half power it runs without problems.
Tomorrow we have Midsummer eve with 24 hrs of sun, major party night but temps are like Christmas time
so heat is welcome!
Cheers again from southernmost tip of Finland, Hanko east harbour.
Stefan
 
Good move. It was looking like that was the next move. As far as the breaker goes- the overheat switch on top of the heater is very unlikely the problem, unless dust or lint has built up on the bottom of it, or the sheet metal below it. Seen it happen a couple of times. That would mean removal of the switch itself, or worse removing the case. That sounds unappealing by the sounds of it. What is more likely is dust or lint built up on an intake grill where the heater draws it's intake cold air. Or crushed or damaged intake or delivery ducting. Check the intake grill and inspect the ducting. If all is good the remove the intake duct from the heater and run it hard. See if the breaker trips. If it still trips then remove the outlet ducting and run it with no ducting, making sure that it does not start drawing in all the hot air blasting out the hot end- vent the compartment if necessary. What is also common is that the breaker itself is bad. It can be a very intermittent problem, but if it trips with no ducting the it is probably the breaker itself. I replace about 1 a year here. They are about $156.00 canadian here. As far as I know they are still available. I ordered one from espar Canada a few months ago. I have only replaced one "switch in 17 years, but many breakers. Hope you have a great time! Good luck in the morning! Greetings from Canada. It is hot here in Vancouver. But down to 2 C up at 100 Mile House BC where we have a cabin. Cheers
 
Brian silk said:
I just wanted to put it out here that I can give service advise on ESPAR brand heaters. I have been an Espar Marine tech for 16 years and know them inside out. You can message me privately if you wish. I will check the General forum regularily.
Click to expand...

Hi Brian. Have an diesel Espar D3L started it last year and it was fne. .tried today and no luck. I hear 2 clicks coming from the control unit area and the fuel pump is silent...no clicking. Removed glow plug..it felt warm to the touch .the fan is not turning at all.
What should I look for??

Thanks
Lloyd T
 
Lloyd T said:
Hi Brian. Have an diesel Espar Hi. #1. Check the voltage on the bottom of the control unit. Red and brown wires in a two pin plug housing. Check before you turn it on, and then turn it on. If the voltage drops below 10.5 then you have a bad connection in the power harness. Very possibly the fuse holder near the battery terminals. If it is ok then check the fuse on the bottom of the control unit. It is for the motor. It is a funny 4 amp slow blow fuse. You have to get it from a dealer, or electronic store. If it is blown it usually means the motor or bearings in the blower are toast. If it is ok check the overheat switch. Press down on the rubber boot up on top of the case. If it clicks then it has overheated. It will reset. If it does not click then obviously it is ok. If you can. Remove the boot and look down inside( probably not,as they are usually crammed up too high. Sometimes the terminals(small push on spades) can be corroded. If they are the you need to remove the heater and case and clean up and replace the spades. Check also that the fan is free turning. If it is not, then the blower has probably seized. Heater goes in garbage then! If all this is ok,then I would probably suspect the control unit. It may be dead,again heater goes in garbage. You can try cleaning up the relay contacts with some Emory paper. Remove the control unit, remove the tape at the bottom, pry up the little aluminum tabs and pull the plastic bottom housing off. Then gently pull out the circuit board. Look for burning anywhere. If it looks ok the clean the three relays contacts. You can tell which one the motor is by putting the plugs back in and pressing the relay ends until one activates the motor. If cleaning does not do the trick then it is toast.
Obviously, check the entire wiring harness and plugs for corroded or loose connections. If it is a 25 1640 then it has a simple open close thermostat, if it is a 251738 then it needs resistance sigmal from the thermostat, wiring connections in the thermostat harnesss are more important.

You can check the glow plug element for eroded spots on the coil, they will glow hot and the rest will not, or there may be a broken coil that may be barely making contact. Do a continuity check between the threaded stud and the flat disk, should be a closed circuit. You can also hang it outside in midair with the wires connected and turn the heater on, weak spots will glow, or if it is a barely connected break, it may spark. There is a small posibility of one of the glow plug relays being bad-the two in the harness. Hope this helps. Post a reult if possible
Click to expand...
 
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My espar D7L starts to vibrate aggressively about 15 sec aftter start up and continues to vibrate for one to two minutes, then the vibration slowly fades away and the espar is able to provide heat.
I would really appreciate your help as to the cause and cure for this.
 
Good day. Pull out the glow plug and attach all wires. Suspend plug insulated or away from the case.put a rag in the glow plug hole. Start the heater for a few seconds and look at the glow plug. It should be getting red hot, and should have a spark going from the centre outwards. If it does not have a spark, then the coil next to the plug is not generating high voltage. Try a second plug if you have one, to verify it is not a bad plug. If another plug preferably new one has no spark, then the spark generator needs replacing. Still available. If you have a,good plug,spark and glow. Then the part is ok. Check that the fuel pump filter on suction side inside pump is clean. Do not open output side of pump. If it is clean leave it in, if it is dirty then remove it and back flush it. Also check voltage at heater when glow plug is on. It should be above 11 volts or so. If the charger is on it should be higher. If it is below 11 volts then you may have a bad power wire connection causing the glow plug to not get hot enough. If all is working,spark,gliw and fuel, then the heater probably has a dirty atomizer insude,and orca degraded liner. It would have to be totally disassembled and cleaned and have the heat exchanger liner replaced. That is still available as well. Hope that helps.
 
Hi Brian, thanks for all your tech support on Espar heaters. Im wondering if there is a metal repalcement fuel line to replace the plastic fuel line to the heater. I have a D4 heater and the plastic fuel line and exhaust line are very close together where they tie into the heater. Any ideas?
 
You can use copper tubing, but the location on the bottom of the heater is safe. Millions out there operating. I have installed hundreds myself. You just need to strap/ secure the line on a direction away from the exhaust elbow. The clear line is 1.5 mm id. That is important. And line you use will have to have the same id. The clear line is handy as you can see the fuel movement. Tiny round bubbles normal, block of air mean starvation or plugged filter, or bubbles bouncing back and forth indicate plugged filter or blocked pickup tube. I would leave it if you can. Just make sure the line does not get any closer to the exhaust than it does right at the connection point. Hope that helps.
 
Brian,

I found this forum when looking for sources around an Espar Hydronic D5SC that is producing a large amount of white smoke at start up and then shuts down. The unit was working well until we used it under very cold temperatures. I do put some winter fuel additive in for winter but I cant imagine that would be the issue.

When attempting to start the unit, I can hear the fuel pump clicking and feel the heat of the glow pin on the side of the unit but the white smoke just pours out for approximately 3 minutes and then the unit shuts down. The white smoke is not warm nor is the side of the unit. It seems like the fuel is never 'lit'. After the 3 minutes, the unit just shuts down and does not attempt to re-start.
I did notice that the intake hose was pointing up against the underside of the body, so maybe it wasnt getting enough air into the unit or there had been something which could have fallen into the intake hose? I have since moved the intake so it would be getting more fresh air but still see white smoke with no heat from the unit.

Any thoughts are very helpful at this point.
 
Hello. I would need to know what series it is. A number on the tag that starts with 25. If it is older without a replaceable atomizing screen then the burner is clogged. New burner. If it is one of the newer ones it will have a replaceable atomizing screen $17. But a bit complicated to replace or explain. Get me that # and I can try and get you the troubleshooting / repair manual. You would have to email me at avalonbaymarine.com contact form on site. I would have to talk to you while you are looking at the manual.
 
Brian silk said:
I just wanted to put it out here that I can give service advise on ESPAR brand heaters. I have been an Espar Marine tech for 16 years and know them inside out. You can message me privately if you wish. I will check the General forum regularily.
Click to expand...

Brian, are you still offering help with Espar? Last June I bought an Island Gypsy 32with a D3L and discovered last month that the diesel heater fan seems to run but no heat. How do I diagnose?
George
 
Yes. Still on it!
It is one of two things. The flame sensor on the top of the heat exchanger, under the black metal case on the hot end of the heater. It may be stuck on hot, so when the heater turns on the ecu thinks it is hot and goes into cooldown and stays there. Or the ecu is fried. To test you need to take the heater off its bracket. Remove exhaust elbow, fuel line and intake off the bottom. Unbolt th heater from the bracket. Undo all the horizontal row of case screws from the front and back. Undo all four of the screws that hold the hot end plastic endhood. If you look at the top hot end, you will see a sensor with a wire going to each side of it.put a jumper across the two terminals and start the heater . If it now turns on the glow plug, and the fuel pump turns on at 25 seconds then it is the flame sensor. If not then the ecu. If it is the flame sensor then good, because you can still get them. , and under $100. If the ecu is bad then $700. Throw out the heater! Not worth it. Obviously. Thus is only applicable if you heater is a 25 1640 model. Not a 25 1738. Numbers are on the tag on top of the heater. If it is a 1640 there will be three plugs in the ecu, if a 1738. Only two plugs. Let me know how that goes. If it is the temp/ flame sensor you will need to remove the galvanized heat shield that covers the flame sensor. It has two little "speed nuts" that push on to little nipples. You gave to carefully pry open the leaves of tgese little clips so you can pull them up and off. Makes more sense when you are looking at them.
 
Brian silk said:
Yes. Still on it!
It is one of two things. The flame sensor on the top of the heat exchanger, under the black metal case on the hot end of the heater. It may be stuck on hot, so when the heater turns on the ecu thinks it is hot and goes into cooldown and stays there. Or the ecu is fried. To test you need to take the heater off its bracket. Remove exhaust elbow, fuel line and intake off the bottom. Unbolt th heater from the bracket. Undo all the horizontal row of case screws from the front and back. Undo all four of the screws that hold the hot end plastic endhood. If you look at the top hot end, you will see a sensor with a wire going to each side of it.put a jumper across the two terminals and start the heater . If it now turns on the glow plug, and the fuel pump turns on at 25 seconds then it is the flame sensor. If not then the ecu. If it is the flame sensor then good, because you can still get them. , and under $100. If the ecu is bad then $700. Throw out the heater! Not worth it. Obviously. Thus is only applicable if you heater is a 25 1640 model. Not a 25 1738. Numbers are on the tag on top of the heater. If it is a 1640 there will be three plugs in the ecu, if a 1738. Only two plugs. Let me know how that goes. If it is the temp/ flame sensor you will need to remove the galvanized heat shield that covers the flame sensor. It has two little "speed nuts" that push on to little nipples. You gave to carefully pry open the leaves of tgese little clips so you can pull them up and off. Makes more sense when you are looking at them.
Click to expand...

Thank Brian. Will be on boat this weekend and will try the above. George
 
Any know why my Airtronic heater will run for about 20 min the shut off. it will not start for about another 30min and then will only run for about a min? This is in a marine application.


Mark
 
Brian silk said:
Hello. I would need to know what series it is. A number on the tag that starts with 25. If it is older without a replaceable atomizing screen then the burner is clogged. New burner. If it is one of the newer ones it will have a replaceable atomizing screen $17. But a bit complicated to replace or explain. Get me that # and I can try and get you the troubleshooting / repair manual. You would have to email me at avalonbaymarine.com contact form on site. I would have to talk to you while you are looking at the manual.
Click to expand...

Brian, sorry for the long wait in the response. The model/version # is 25 2217 it looks like. Not sure if that is a newer one like you mentioned. When running the heater, it starts to blow white smoke after about 30 seconds of the unit starting up.

Appreciate it if you are able to get me the trouble shooting/repair manual. I am temped to dis-connect the fuel like into the inlet side of the fuel filter to see if I can pull the screen to see if it is clogged. When the unit started to blow white smoke, it was very cold out and I wonder if it got gelled up or something?

Thanks, any help is appreciated.
Jason
 
first check voltage at the heater, before turned on and after . if it drops below 10.5 v then the heater will not run and shuts down. If it does drop then check all electrical connections on the power wires , and obviously the battery condition. If the voltage is good, then remove all ducting and try to run the heater, this will remove overheating shutdowns as the cause. If the heater now runs without ducting then check all ducting for restriction. Also check all connections in the harness to the fuel pump and thermostat for corrosion. Other than that you will probably have to have someone with a fault code retrieval device pull a fault code out.
 
Hello Brian

I have an Espar D4L that needs some help, for the most part it starts up fine (45 to 60 seconds with a little bit of gray/white smoke) heats up nicely for 5 minutes or so and then what I figure might be the over-temp breaker pops and the heater starts the cool down procedure.
I notice that my intake silencer is damaged, also with an infrared thermometer I am getting temperature of 110 Celsius on the heater output ducting and about 35 to 40 Celsius at the cabin output.
Any Ideas

thanks, Dennis
 
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