Looking at the animation there's only one place to install the heater pump and thats between C(thermostat) and D(water pump).



However, actually doing this is more difficult than I'd expected because that part of the system on the JTD is intergreated into the block, it also requires the highest flow rate as all 3 systems(block, cab heater, radiator) are supplied from that pipe, not sure fitting something in there that could reduce the flow would be a good idea.

I'm thinking a small bore bypass pipe, pump to thermostat may work quite well. Small bore fits the new heater pump perfectly and shouldn't effect flow rates too much when the car is running. If I'm bored later I'll take the covers off our JTD and see if its possible.

sludgeguts said:

Just got this pic off the Kenlowe site which shows their installation on the return hose from the matrix. I wonder if this matrix has a shutoff valve? In which case, I wonder what the built in pump is doing to circulate coolant. I'll send them an email.

Click to expand...

This setup looks to me like its being used as a cab heater to heat the cab, not the engine.

The kenlow heater is 3kw, so it will have enough grunt to heat the block and interior matrix.
It doesn't really matter what direction the pump, pumps in as its not running with the engine on, and even if it was on and the pump was fighting the flow, its only hot water and the engine is not going to overheat as the kenlow unit switches off near the correct temperature and even if it didn't the main thermostat in the block would open and dump any excess heat into the main radiator.

It might be an option to install the heater in parallel to the heater matrix, ie between J and the return, heat will circulate regardless of whether the heater flow valve is on or off, the heater matrix has a certain resistance to flow as does the block so the heat will be proportioned accordingly. If the heater valve is off then the block gets all the heat, if its on or patially on then both the heater and the block get heat, either ways a win.
A drawback might be hot water short circuiting the heater matrix through the pump once the engine is started, but the answer to that can probably be worked out by pouring water through the pump and seeing if it restricts or not. Once the engine is started all the heat and cold mixes up pdq, but the overall aim of getting some heat in there has been achieved. Whatever the solution good luck.

johnhififan said:

It might be an option to install the heater in parallel to the heater matrix, ie between J and the return, heat will circulate regardless of whether the heater flow valve is on or off, the heater matrix has a certain resistance to flow as does the block so the heat will be proportioned accordingly. If the heater valve is off then the block gets all the heat, if its on or patially on then both the heater and the block get heat, either ways a win.
A drawback might be hot water short circuiting the heater matrix through the pump once the engine is started, but the answer to that can probably be worked out by pouring water through the pump and seeing if it restricts or not. Once the engine is started all the heat and cold mixes up pdq, but the overall aim of getting some heat in there has been achieved. Whatever the solution good luck.

Click to expand...

On the dobbin, the flow & return are easy to spot & get at, with plenty of access to insert something. I was wondering about cutting both pipes, inserting a Tee piece in each with maybe a narrower bore pipe to bypass the matrix. The heater pump shouldn't have any problem pushing fluid through a slightly narrower bore but with the engine running, the coolant would hopefully take the wider bore to the matrix (path of least resistance), so not taking quite so much (if any?) hot coolant away from the matrix.
As I said though, If only we had a decent pic from a decent workshop manual (anybody??) showing the exact layout of the pipes it would be so much easier to determine where best to site the heater. It's all well and good looking at pics from the web but these are not model specific & dobbin might just have somewhere handy to tap into. Heck, it may even be possible that the control valve for the matrix can be tricked into allowing a bypass?

johnhififan said:

It doesn't really matter what direction the pump, pumps in as its not running with the engine on, and even if it was on and the pump was fighting the flow, its only hot water and the engine is not going to overheat as the kenlow unit switches off near the correct temperature and even if it didn't the main thermostat in the block would open and dump any excess heat into the main radiator.

It might be an option to install the heater in parallel to the heater matrix, ie between J and the return, heat will circulate regardless of whether the heater flow valve is on or off, the heater matrix has a certain resistance to flow as does the block so the heat will be proportioned accordingly. If the heater valve is off then the block gets all the heat, if its on or patially on then both the heater and the block get heat, either ways a win.
A drawback might be hot water short circuiting the heater matrix through the pump once the engine is started, but the answer to that can probably be worked out by pouring water through the pump and seeing if it restricts or not. Once the engine is started all the heat and cold mixes up pdq, but the overall aim of getting some heat in there has been achieved. Whatever the solution good luck.

Click to expand...

I imagine that the pump in the heater is a standard water pump which tends to be contactless (as it is submerged constantly) so wouldn't be subject to burnout.
I've not heard back from kenlowe yet but looking at the various installation diagrams around the web, I cannot help wondering if the control valve for the heater matrix has to be 'told' to close. In other words, if you are running the engine with the heater on, the valve is open (obviously), if you then turn off the engine, does the valve remain open or close automatically?

If the pump did not restrict flow I'm 99% sure the heater pump could be installed in the pipe circled in red(item 6).
This pipe sits inline between the water pump and the thermostat on the 8v 1.9 JTD, I'm sure the layout is very similar on a Doblo.

This is the best pic I can get off the poxy doblo disk. Had to screengrab, crop then enlarge - which then gives a distorted pic & the pic is so cluttered that is't hard to follow.
The larger pipe ( 8 ) is labelled "rigid inlet pipe to pump". It looks like this drops down to a Tee piece, one part going to the rad lower hose, the other being a smaller bore pipe connected to what may be "engine coolant temp sensor" ( 3 )- which looks likely to link to the stat ( 4 ). The forward part of this goes to the rad upper hose, the rest? who knows but I have to assume that coolant goes to the pump via the rigid pipe, through the block then back to the stat.
The pipes to the matrix will be blocked with the valve, the pipe to the rad will be blocked by the stat (when cold & with engine off).
So now I just need to determine if there is a flexi hose joining the rigid inlet pipe to the pump - so I may have more room to work) OR I may have to put in a couple of longer hoses to replace (your pipe circled red) & mount the heater to something solid - I may even be able to use this to my advantage by running at least one hose directly under the battery to get a 'toofer' (mount the heater AND give warmth to the battery).

Most cars in the Depths of cooler climates have night block heaters, i bet any money Fiat give the option in countries with seriously cold weather. You basically plug your car in over night and it keeps the engine warm, saves you having to drain EVERY fluid every night and take it in the house by the fire,
EU market OEM option maybe?

Or just buy a KAT'S,
remove core plug, fit, alter voltage then sit back and enjoy toasty engine
Amazon.com: Kat's 11612 600 Watt 41mm Frost Plug Heater: Automotive
Or
Amazon.com: Kat's 14800 600 Watt 2" Lower Radiator Hose Heater: Automotive

The "rigid inlet pipe to pump"(8) is exactly the same as items 1 and 5 in my diagrams.

The "rigid inlet pipe to pump"(item 1, 5 and 8) bolts direct to the engine, near the water pump, no "flexy hose". But the other end has a 20mm bore(approx) pipe(circled in red) that connects it to the thermostat housing. This is the only place I can find that might be suitable for your pump.

The engines water pump and the heater pump your installing are both centrifugal pumps so neither would restrict the flow very much when the other is operating.

As you say, extending the pipes to suit a mounting position on or near the battery box would be very usefull but before mounting the heater perhaps a couple of test warm ups would be wise.

If it works I may install one myself.

That bottom hose heater that Grande posted looks great and must be easier to fit, trouble is its not UK.

johnhififan said:

That bottom hose heater that Grande posted looks great and must be easier to fit, trouble is its not UK.

Click to expand...

Yes, however, that simply heats the coolant, relying on convection & associated physics to heat the engine.
Whereas this one has an internal heater AND a pump. I'm assuming from the inlet/outlet configuration that the pump is centrifugal.
The pump pushes heated coolant around the block so ensuring an evenly warmed up engine. (I did see a thermal image showing the difference between pumped & non pumped heater but can't find it at the moment).
I know they are pushing the product but some of what is mentioned http://www.kenlowe.com/pre-heaters/cars/whatwill.html seems to make sense

My doblo disk makes no reference whatsoever to a shutoff valve for the heater matrix - yet there must be one else you'll get boiling hot coolant flowing through in the middle of summer (in which case, where is it? - the one on my lad's fiesta is easy to spot as it's fixed inline to both hoses as they leave the engine bay) . Even if the blowers were diverted off the matrix, there would be some residual heat coming out ( ).
The webasto parking heater makes reference to heating the car's interior & defrosting the screen - so can I assume that installation also includes some sort of bypass circuit providing current to the valve & blowers? (otherwise it could pump coolant day & night & the car's interior wouldn't warm up (?) )

The 'shut off valve' on the fiesta is not a shut off valve. For some reason ford were feeling strange and decided to use a solenoid valve to control the flow of coolant into the matrix and thus the temperature of the cabin heater, normally as is most probably the case with your Doblo, the coolant does run continuously into the matrix then the air flow thought the cabin heater is diverted by moving flaps through the matrix or around it, I've not found other cars that are the same as the mk4 fiesta.

sludgeguts said:

My doblo disk makes no reference whatsoever to a shutoff valve for the heater matrix - yet there must be one else you'll get boiling hot coolant flowing through in the middle of summer (in which case, where is it? - the one on my lad's fiesta is easy to spot as it's fixed inline to both hoses as they leave the engine bay) . Even if the blowers were diverted off the matrix, there would be some residual heat coming out ( ).
The webasto parking heater makes reference to heating the car's interior & defrosting the screen - so can I assume that installation also includes some sort of bypass circuit providing current to the valve & blowers? (otherwise it could pump coolant day & night & the car's interior wouldn't warm up (?) )

Click to expand...

The heating unit of the Doblo is similar in design to other Fiats. Its a compact design that incorporates, fan, heater matrix, solenoid controlled flaps etc..

The shut off valve must also be inside the unit, either electrically(aircon) or cable(non aircon) operated, unless a flap is used to divert air away from a permantly heated matrix. Can't see that working very well in the sumer when the aircon is turned to cold. Heat from the matrix would cause the aircon to work overtime.

I suspect their parking heater is limited to certain cab heater designs.

Shadeyman said:

The shut off valve must also be inside the unit, either electrically(aircon) or cable(non aircon) operated, unless a flap is used to divert air away from a permantly heated matrix. Can't see that working very well in the sumer when the aircon is turned to cold. Heat from the matrix would cause the aircon to work overtime.
.

Click to expand...

I have to agree with you on that - although I have been known to be wrong. I've only worked on 4 heater matrices over the past 30 years and all have had some sort of method to stop the matrix getting toasty in the middle of summer.
Like you, I find it unbelievable that you will have a very efficient radiator, radiating some serious heat on a hot summer's day. If only we had a decent workshop manual to pore over (heck, I'd settle for some clear images on a parts disk!).

why not just put car in garage overnight seems like a lot of trouble to make the car start easier in colder conditions i would agree if we lived in norway and -20 degrees but not just living south of hadrians wall as for extra wear on engine i dont know anyone who has a modern car ie 1990 onwards car that has worn the engine due to starting it in the uk cold weather especially with the thinner viscosity oils that are designed for cold starting .but thats just my opinion.
this reminds me of the americans spending £1million on developing the pen that would write upside down when in space !
the russians took a pencil and sharpner with them into space

simples

ferox9311 said:

why not just put car in garage overnight seems like a lot of trouble to make the car start easier in colder conditions i would agree if we lived in norway and -20 degrees but not just living south of hadrians wall as for extra wear on engine i dont know anyone who has a modern car ie 1990 onwards car that has worn the engine due to starting it in the uk cold weather especially with the thinner viscosity oils that are designed for cold starting .but thats just my opinion.
this reminds me of the americans spending £1million on developing the pen that would write upside down when in space !
the russians took a pencil and sharpner with them into space

simples

Click to expand...

If I had a garage, I wouldn't fill it full of the crap that you generally see in them when people open the door - £10k + motor sitting out in all weathers whilst a £50 BBQ and a £120 lawnmower are tucked up for the night.
And whilst there aren't any / many tales of worn engines out there, how do we know that the shock of taking an engine from an overnight of -10 (and we've recorded quite a few of those recently) to instantly hitting combustion temps isn't damaging? (and at -10 deg C, a good battery will be operating at around 60%)
OK, so the lump might get away with it, but what about all those other components? Can we honestly say that HG failure isn't down to these sudden changes in temp? (or any of the other flimsy gaskets). I had an 8y/o astra fail on me one winter's morn, as soon as it fired a piston shattered leaving the con rod flailling inside the pot - causing some serious damage to the walls. Thermal shock? Just one stress too many? I know it hadn't been twiddled with as I bought it at 3y/o as a fleet car (although this one had the same driver from new)

As for the story about NASA spending $1million on space pens whilst the russians took pencils, I think you'll find that it was Fisher who spent the $1million, not NASA. The Americans also used pencils on the space programmes. they later bought into the fisher space pen (along with the Russians).

At the end of the day, it's not a very expensive item & if it means I can get into a toasty warm car on a cold morning...

So, have you decided on a location and how you plan to connect it yet?

If the definitive answer on the valve is that there isn't one then I'll chop the hose coming out of the matrix. (but I'm still intrigued as to what happens to all that heat, it's a very confined space for the high temps).

Just got to buy some additional hose and connectors.

I'm also looking round for a small, flush socket with a flip cover. I'm sure you used to be able to buy the IEC sockets (the ones that accept kettle / computer leads which could be flush mounted & had a spring-loaded cover - or even a waterproof trailling socket that I can fix somewhere convenient.

The only place I've ever seen an IEC with a splash proof flap was on our old Flymo. Perhaps you could scavenge one from someones old Flymo?

or


http://www.tdspares.co.uk/proddetail.asp?prod=fly022&cat=89

Shadeyman said:

The only place I've ever seen an IEC with a splash proof flap was on our old Flymo. Perhaps you could scavenge one from someones old Flymo?

or

http://www.tdspares.co.uk/proddetail.asp?prod=fly022&cat=89

Click to expand...

How interesting - an electric lawnmower - so not allowed to use in the rain (for obvious reasons). Only ones I've ever seen on those things have been the simple push fits. Thanks for the heads up as I was kinda hitting a brick wall.
And for £6 (and on ebay with free delivery), it's not going to break the bank if I play around with it to mount in/under my bumper (or even if I add a double bracket to my towbar?) - that screw on the side looks temptingly like somewhere I could affix some sort of bracket to help me mount the thing.

My initial thoughts are to mount this beside the towbar & cable tie the cable along the underside of the car & up into the engine bay (maybe on the fuel line? - not sure what else suitable is underneath 'til I have a look).
Interestingly, I came across a thread on an aircraft forum (they use preheaters on single props) & a few posters seemed very worried that the car body might somehow become live when this is plugged in. I wonder how my RCDs and ELCB will handle this scenario?