I think I found a heater booster, but no switch

2

220629

Well-known member
Yetimen Appilachian said:
Guys I need guidence too.
It appears I have no timer or wiring for a timer that may have been removed.
...
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All this information is out in other threads. I am repeating. A search can be your friend.

The basic Espar heaters are a small self contained oil burner furnace as to firing. The heaters can be installed stand alone in boats and vehicles. The little furnace has a built in control module for the ignition, blower speed, flame monitoring, operating temperature control, and overtemp safety monitor.

To just fire up the Espar furnace needs a fuel supply (pulse pump), combustion air (internal fan), and an ignition source (glow pin).

The basic external requirements to fire up are:

Constant 12 volts to pin #1.
A proper negative ground connection pin #2.
A connection (wire) out to the dosing pump pin #4 (It is a conditioned pump signal. Not just 12 VDC.).
A 12 volt enable signal to pin #6.
A 12 volt enable signal to pin #7.

Pin #5 is for communication. It is not required.

The circulation pump is not required for the heater to fire up. The Espar control has no idea what the MB aux electric coolant pump is doing, or not doing until the heater go to over-temperature. Without proper coolant circulation the Espar heater will shut down on overtemp safety in a short time.

The Espar heater does run through an internal system check before firing. If there is a problem with the glow pin, flame sensor, blower, etc, then that will prevent the Espar heater from getting to startup.

Here is a basic diagram.

10.3.3 Booster.JPG

Added: As Vanski pointed out, the Espar coolant type heaters can even be test fired with no coolant. I wouldn't allow it to run for more than a very short time without coolant though. It will very quickly over heat and stress components.

vic
 
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T

tinman

Well-known member
Arnie_Oli said:
I will be reading any replies you get!

I am in a similar position here in the UK. Have the bow tie switch, red led comes on, heater is there under the bonnet, but it doesn't come on. I am also looking to add the 7 day timer to mine.
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Sounds like mine, which is to say very quiet. I pulled mine, took it apart and checked all the components. All OK, but I have no way of checking the control unit on the heater itself except functionally. Doesn't work, so I guess it's shot.
 
2

220629

Well-known member
I was trying to edit some of my posts. Now my head hurts.

I'm confused.

Will the member who has the Espar heater with the solid, non-working Bowtie center medallion please raise their hand.

vic

Update: Found it. I didn't go back far enough in the earlier posts.

brutimus said:
Ha! I promise you, it doesn't move one bit. It's as rock solid as anything. Any photos of the espar switch I've seen, there's a little wavy bacon logo to the left of it. I don't have a logo, but after very close inspection with a headlamp, I can see a spot for an LED. Also, those logos appear to be painted on to a black surface with a clear plastic surface over it, so I doubt it's been able to fade or rub off. There's no sign of any residual paint where the wavy bacon logo ought to be.

I've jiggled it, rattle it, thumped on it, blown on it. Doesn't move. =( How hard is the dash to get apart, I want to look at it from the back side.

Also, thank you for the beautiful drawing. =)
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I misread this post.

CruisnDiesel said:
I have the now famous "bacon bowtie" OEM booster heater [added: not the switch]. If I do the mod to run the booster with engine off I need an electric coolant pump. Does that exist in combination with the OEM booster, or does it rely on a engine run collant pump?
Bob
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glasseye

glasseye

Well-known member
Awesome thread, boys. A couple of questions, if I may.

1) Any idea of the combined load in amps for the Espar, the coolant circulating pump and the blower fan? In other words, how long can I sit in the back of the van with the engine off, the heater on, reading a Tom Clancy novel before I run the battery down so low I can't start?

2) Any reason why I can't run this entire system from my aux battery so as to render question 1 moot?

3) The Espar needs two electrical signals according to Vic. 12VDC continuous to several locations on the Espar to power the unit AND a 12VDC "conditioned" signal. That is presumably the pulsed signal that's part of the temperature control feedback, right?. So, can I have a simple switch anywhere in the cargo area that does all of the above?

If the heater control switch is reachable without getting out of bed, I won't have to put my pants on at -15C like that one time in Wyoming. :idunno:
 
2

220629

Well-known member
CruisnDiesel said:
I have the now famous "bacon bowtie" OEM booster heater. If I do the mod to run the booster with engine off I need an electric coolant pump. Does that exist in combination with the OEM booster, or does it rely on a engine run coolant pump?
Bob
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Was this answered?

I believe that the aux electric coolant pump is standard equipment on all NAS aka NAFTA 2004 - 2006 OM647 engine Sprinters. The aux electric coolant pump circulates coolant through the EGR.

For the NAS aka NAFTA 2001 - 2003 OM612 engines I'm quite certain that the only time an aux electric coolant pump is included is when there is an Espar heater ordered. (I may be wrong. :idunno:)

So basically, if you have any variation of the optional Espar heater you should have a pump.

vic
 
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2

220629

Well-known member
glasseye said:
Awesome thread, boys. A couple of questions, if I may.

1) Any idea of the combined load in amps for the Espar, the coolant circulating pump and the blower fan? In other words, how long can I sit in the back of the van with the engine off, the heater on, reading a Tom Clancy novel before I run the battery down so low I can't start?
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The Espar native control module has a low voltage monitor and shut down. That *should* leave enough juice to start your engine. One factor against that is if the ambient is extremely low. In that case the battery output is compromised, and the engine may be very cold. Those two factors will work against you.

glasseye said:
2) Any reason why I can't run this entire system from my aux battery so as to render question 1 moot?
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There are threads which discussed that. To do it correctly takes more than just switching a couple of wires. Added: Mixing of aux battery and starting battery voltages to an Espar unit has some of the same potential pitfalls encountered when powering a head unit (radio) from two separate battery systems. You can fry some expensive electronic components if it isn't done correctly.

glasseye said:
3) The Espar needs two electrical signals according to Vic. 12VDC continuous to several locations on the Espar to power the unit AND a 12VDC "conditioned" signal. That is presumably the pulsed signal that's part of the temperature control feedback pump operating signal, right?. [Yep... now.]
Click to expand...
The 2 enabled signals are a regular old 12 VDC.

glasseye said:
So, can I have a simple switch anywhere in the cargo area that does all of the above?

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Once the controls are set up for constant run an enable switch could basically be mounted anywhere.

:cheers: vic
 
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ECU

ECU

2006 T1n 118 Sprinter
I've done it. Not exactly sure that the fan is running from the aux battery.
But you could simply think of the aux battery as the jump battery when your standard battery goes down. In essence, leave everything on the start battery and the aux is your reserve.
Either way is actually quite easy. I have it done in a way that I can revert back to factory quite easily. Just replace fuses.
 
A

Arnie_Oli

Member
Well I think my Espar unit has seen better days. Appears that water has been dripping from the cabin air gasket that mates with the bonnet onto the heater and the battery tray. Result is one really rusty Espar, I will need to take it out and see if it can be salvaged.
 
autostaretx

autostaretx

Erratic Member
glasseye said:
1) Any idea of the combined load in amps for the Espar, the coolant circulating pump and the blower fan? In other words, how long can I sit in the back of the van with the engine off, the heater on, reading a Tom Clancy novel before I run the battery down so low I can't start?
Click to expand...
Many years ago when our Sprinter was young, i spent a slightly below freezing Xmas night in Maple Ridge BC. We got up every two hours or so (whenever we shivered awake or the bladders called) and punched the red button on the 7-day timer.
The front cabin fan was on 2.

Figure at least an honest 6 hours of operation from the year-old OEM starter battery, and no problem starting in the morning ... after breakfast (so the engine had an hour or so to cool down a bit)

If you were to ask me my guesstimate on the load, it would be 3 to 5 amps ... cabin fan speed being the swing vote. (yeah, i could go measure it, but i'll just guess given the manual's specifications).

--dick
 
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glasseye

glasseye

Well-known member
Thanks, boys. Several hours worry-free operation would be adequate. I don't see myself running such a system overnight, I'd just like to avoid the morning getting-dressed-in-the-cold scenario. This sounds like my next big Frito project.

Oh, and by the way, Dick, Maple Ridge, BC hardly qualifies as "winter", ever. Even at Christmas. :tongue:
 
davisdave

davisdave

2005 140 tall passenger
I think the dash fan takes up to 4.6 amps, and the water pump is less than an amp. Both of these items are powered by the wire you supply (existing plug behind shifter powers the fan, and the green/red wire you cut for the water pump). So, you can run these wires to the aux battery if you like:snore:
 
surlyoldbill

surlyoldbill

Well-known member
yeah, NONE of the lights come on on my HVAC controls, not even the +bacon indicator LED, although I hear the jet trying to take off by my front tire when it's "on". I need to get around to replacing those bulbs or something.
 
K

Koaga7

New member
brutimus said:
I stumbled across a thread last night saying that nearly all T1N's shipped with espar heater boosters. I'd previously noticed the little silver muffler in the front driver's side wheel well and didn't know what it was. I just went out and looked under the starter battery and I'm pretty certain there's a heater under there. I see two black lines come up and out and a little clear line that I presume is fuel. I haven't really dug into it, but it looks like what everyone describes as the heater.

But I have no heater booster switch in the cab! I just bought this van nearly a year ago, so it might still have some features I don't know about. But why would I not have a switch.

Oh also the data card claims is has a heater booster as well. It also claims it has heated mirrors (which would be great if there was a button for that, too!)

Any ideas?
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My 2004 Sprinter has the same situation. A heater booster (Espar) under the headlight with no evidence of it on the dashboard. I never would have known, that it had a heater booster, except when it was one of the few 10 degrees Fahrenheit mornings in Atlanta, GA, I heard the heater booster's pulse fuel pump thumping & investigated, finding the heater booster.
I believe, that many, if not most T1N Sprinters are like ours, but because the heater booster only comes on passively, when it's really cold, solely to keep the engine running at a temperature warm enough to be efficient, most people never realize, that a heater booster exists on their van, so they don't weigh in on forums concerning it.
Apparently, Using the same Espar diesel heater, MB offered several options, from a few with no Espar at all, to most with a clandestine Espar to boost engine heat when well below freezing, then one with the bowtie switch, then one with a 7 Day timer, with little info provided to owners or service techs explaining these various options & their differences.
To this day, I can't find at exactly what temperature my booster comes on? I've read 41 degrees Fahrenheit, but I've only noticed mine coming on, when the temperature is in the teens or lower. Hopefully, one day I'll get around to doing some of the modifications discussed here, in order to get the most out of the Espar heater booster.
 
K

Koaga7

New member
Cheyenne said:
Operation of the Espar Heater Booster is fully explained in the 2004 Owners Manual from page 122 on...


And the standard installation in a T1N with the Bow Tie button does not have any ambient temperature restriction on operation. They will work at any ambient.
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My 2004 T1N Sprinter has no bowtie switch or other evidence on the dashboard, that my heater booster exists & page 122 & the following pages in the manual don't address or otherwise address this. Like I said, many T1N owners probably don't even realize, that they have an Espar heater booster under the headlight, since there's no evidence for it on their particular dashboard, not to mention, that particular configuration, booster with not even a bowtie switch, isn't mentioned in the manual. Mine comes on the few times of year, that the temperature is in the teens or below in my area, and if I hadn't heard it's pulse fuel pump (also the "jet" sound), I'd have remained oblivious to the fact, that I had an Espar under the battery.
 
Cheyenne

Cheyenne

UK 2004 T1N 313CDi
What option codes do you have listed on your Data Card?

HZ9 Heater booster is the option with the Bow Tie button.
 
K

Koaga7

New member
Cheyenne said:
What option codes do you have listed on your Data Card?

HZ9 Heater booster is the option with the Bow Tie button.
Click to expand...
Mine is "HZ9 Heater Booster, Diesel" according to the data card. Still no bowtie button? I know, that it's supposed to be right above the "rest" button & below the AC button, but it's just a stationary bowtie which isn't a button nor is it marked as such on my van. Would like to have one, so I could exercise the booster off season, especially since I just rebuilt the Espar this year. Btw: Thanks for getting me to look up my data card. I was able to use my vin. I hadn't done that before, even though I've had the van for 6 years. It has good information.
I believe, that I'm correct in saying that many vans with heater boosters were delivered without the bowtie button. I fixed an AC problem on the control unit a while back, & it appeared to be the original one, plus, there's the original poster on this thread. Maybe one with the bowtie button will show up in the junkyard, as they are pretty expensive on ebay.
 
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