Ford Transit USA Forum banner

Espar B4L Heater not starting at Elevation

32490 312
So I installed a Espar B4L in my 2020 transit, under the passenger seat and have a problem with the heater starting when I am at elevation.

I live in Boise ID, at around 3k feet elevation, when down here in the valley my heater starts 99% of the time without issues. When I travel to my local ski area around 6800K feet the heater NEVER starts first try and generally will take around 30+ minutes of trying to get the thing started. Once it does starts at elevation, it will run absolutely fine stopping and starting. When I got back down in elevation it also will always start fine, and then back up to elevation I again have the problem.

Ive completely taken apart the entire gas line from the pickup in the tank all the way to the heater, ensuring rise, fittings, etc are perfect... still have the same problem of getting it started at elevation.

Heatso has been sorta OK to work with, but I feel like they dont really know either. They will be sending me a new ECU (when they get them in a couple weeks).

Has anyone had this problem, is there a trick to getting it started I could use until i get the root cause sorted?

Appreciate any pointers!
261 - 280 of 313 Posts

·
Registered
2022 U8U
Joined
·
653 Posts
My understanding is that downstream of the pump it is normal for there to be a stream of very small, uniform bubbles spaced abut 1/2" apart. That is how my properly-operating D5 works.

However, if you look around the Web, you find a diversity of views on this topic.
 

·
Registered
Joined
·
37 Posts
I don’t know if mine generates bubbles or not. But i do know the thing works fine. Starts up every time and heats with no errors. Do you still get error codes?

If so, maybe it is not even the bubbles that are causing the codes.……

When it won't make it through the start cycle it's always the same fuel related (ie temperature) codes. Sometimes after multiple tries it will run a full cycle ( I have it set to run 60 minutes). I haven't tried very many start cycles since the latest changes. I actually have other stuff to do. I have been told bubbles are bad yet when it does run a full 60 minutes it's still making bubbles. So, how do you stop making bubbles?
 

·
Registered
Joined
·
37 Posts
My understanding is that downstream of the pump it is normal for there to be a stream of very small, uniform bubbles spaced abut 1/2" apart. That is how my properly-operating D5 works.

However, if you look around the Web, you find a diversity of views on this topic.

Interesting that the diesel heater also makes bubbles. I have one (diesel fired heater) but it has always worked fine so I never looked to see.
 

·
Registered
Joined
·
37 Posts
On the first test with partial blockage of the output was positive. Ran through the start cycle for the first time at 36F ambient. Can't believe this hasn't been common knowledge for all the heaters with no output ducting. Will take time to verify but looks promising.
 

·
Registered
Joined
·
1,371 Posts
What did you do to the output? ( fuel output?)
 

·
Registered
Joined
·
37 Posts
What did you do to the output? ( fuel output?)
In order to raise the temperature of the combo sensor to satisfy the ECU requirement I partially blocked off the hot air output. Seems that without a duct to provide some back pressure, the temp requirements are so narrow that on a cold morning it can't do the complete start up cycle. At least that's my current working theory.
 

·
Registered
2021 HR Extended AWD Transit T-250
Joined
·
355 Posts
On the first test with partial blockage of the output was positive. Ran through the start cycle for the first time at 36F ambient. Can't believe this hasn't been common knowledge for all the heaters with no output ducting. Will take time to verify but looks promising.
Awesome news that you now have a definitive cause & solution, even if the solution is a bit of a hack. Maybe bring this up in the automation thread to develop a temperature activated baffle on the heater warm air output since anyone that installs the heater in this location is likely to have the same problem.
 

·
Registered
Joined
·
37 Posts
Awesome news that you now have a definitive cause & solution, even if the solution is a bit of a hack. Maybe bring this up in the automation thread to develop a temperature activated baffle on the heater warm air output since anyone that installs the heater in this location is likely to have the same problem.

Had another successful cold start up this morning. Since I have a "spare" combo sensor I'm thinking I could change the resistance on the low temp side and try to get it to satisfy the ECU at a lower temp. Can't believe Espar isn't aware of this issue????
 

·
Registered
2020 High-Extended AWD EcoBoost Cargo with windows
Joined
·
4,388 Posts
Had another successful cold start up this morning. Since I have a "spare" combo sensor I'm thinking I could change the resistance on the low temp side and try to get it to satisfy the ECU at a lower temp. Can't believe Espar isn't aware of this issue????
Would just be nuts if this turns out to be the factor... or even A factor. If so, something as simple as which vent one uses could change that pressure. 🤔
 

·
Registered
2021 HR Extended AWD Transit T-250
Joined
·
355 Posts
Can't believe Espar isn't aware of this issue????
I updated the Espar troubleshooting post on my website and sent a note to Mike on this. Hopefully, we can get the word out for other folks dealing with this and maybe Espar will address it. This seems like a worse issue than I experienced since the fault codes in this situation are actually misleading and detrimental to the troubleshooting process.
 

·
Registered
Joined
·
81 Posts
I just got mine wired yesterday. I ran it for 5 hours on the infinity setting at max temperature. No issues. I did have to hook up the yellow wire through the altitude sensor though, it wouldn't start otherwise.
 

·
Registered
Joined
·
37 Posts
I updated the Espar troubleshooting post on my website and sent a note to Mike on this. Hopefully, we can get the word out for other folks dealing with this and maybe Espar will address it. This seems like a worse issue than I experienced since the fault codes in this situation are actually misleading and detrimental to the troubleshooting process.
Good on you. I hope we can spare others the long frustrating troubleshooting process we have been through.
 

·
Registered
2021 HR Extended AWD Transit T-250
Joined
·
355 Posts
I went back & forth with Mike a bit yesterday. He's not buying the working theory we have here. His first explanation is that on the cold start mornings, the heater goes into boost mode and boost mode is more susceptible to the fuel cavitation. On warmer mornings, the heater doesn't go into boost mode and can better tolerate the cavitation bubbles in the fuel line. He's trusting the fault codes and still believes that it is a fuel supply issue (cavitation).

So why would the warm air exhaust back pressure affect this? The heater heats up faster and gets out of boost mode.

With our very small sample, we see a correlation of folks with the cold start issue that have no warm air duct and those with ducting not having the issue. He didn't have an explanation for this.

Anyway, I don't know that we'll get to the bottom of this unless someone with the issue gets hooked up to the EasyScan diagnostic tool to watch the sensors in real time. In my case, this was very enlightening.

At least there seems to be a workaround.
 

·
Registered
Joined
·
37 Posts
I went back & forth with Mike a bit yesterday. He's not buying the working theory we have here. His first explanation is that on the cold start mornings, the heater goes into boost mode and boost mode is more susceptible to the fuel cavitation. On warmer mornings, the heater doesn't go into boost mode and can better tolerate the cavitation bubbles in the fuel line. He's trusting the fault codes and still believes that it is a fuel supply issue (cavitation).

So why would the warm air exhaust back pressure affect this? The heater heats up faster and gets out of boost mode.

With our very small sample, we see a correlation of folks with the cold start issue that have no warm air duct and those with ducting not having the issue. He didn't have an explanation for this.

Anyway, I don't know that we'll get to the bottom of this unless someone with the issue gets hooked up to the EasyScan diagnostic tool to watch the sensors in real time. In my case, this was very enlightening.

At least there seems to be a workaround.
Interesting. There are bubbles on the pump output ALWAYS. Cold, warm, and in between, before and after all the changes I've made. If there is a fix for that, I'd love to hear it. And I'd love to hook up a scanner. Tell me where? Bottom line is, it needs some better engineering!
 

·
Registered
Joined
·
37 Posts
Is it possible to have an installation (gasoline) that sucks fuel up a standpipe, even a 2mm ID Espar, that does not cavitate and make some bubbles downstream of the pump? If it"s as difficult to do as it seems, then what is the downside to lowering the temp threshold so the **** thing works for less than perfect installations. Is the goal "I don't want it to work unless the installation gods are happy?" Or "Let's make the majority of customers happy by allowing it to work in less than "perfect" installations? How difficult would it be for the factory to make that adjustment? Either send out a replacement combo temp sensor or recall and reflash the ECU?
 

·
Registered
2022 U8U
Joined
·
653 Posts
Here is a video of what my fuel line looks like between the pump and heater, lots of bubbles and no errors (anymore). Does yours look better or worse?
My post-pump bubbles are much smaller and more uniform than that. It is diesel, though, so perhaps apples-and-oranges. I will report on petrol experience if Ford ever builds our new van.
 
261 - 280 of 313 Posts
Top