Hi all. Just a quick question for those of you with diesel heaters. I have been looking on ebay and I noticed they seem to vary between 2KW to 5 kw I'm looking for one for a 18 foot van can any one tell us what size they are using, how efficient it is, and how much fuel it uses. Also has any one had any problems with the cheaper units. Landy
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In our 24' Jay6co we have a cheap 2kw one from Pinnacle Wholesalers here in Ballarat. Performs extremelly well. Not sure how much diesel it uses. This will be our 3rd winter with it I think.
If I was to buy one again, I would be looking carefully at the temperature control, and how it works. Out heater is just too hot, and doesn't seem to modulate to the temperature setting. It is just the straight dial, and I would be looking at the digital temperature control version.
I think part of our problem is that the temperature probe is at the inlet of the heater, and I have a long inlet duct on that side. So by the time the heated air is returned to the heater, it has cooled, so the unit is getting a false reading. We haven't had a real chance to use it for any period of time, as when we have had it on we're too hot. I think its 2.5kw in a 24 foot van.
If I was to buy one again, I would be looking carefully at the temperature control, and how it works. Out heater is just too hot, and doesn't seem to modulate to the temperature setting.
An excellent observation and comment.
Diesel heaters do not have variable heat output control, I believe, they are either on at maximum output or off at zero output. So, in order to maintain a comfortable caravan temperature the heater needs to be switched on and off at appropriate time intervals.
If an On/Off room thermostat is used it simply ramps the heat up until it hits set point then switches the heater off. Thermal lag and overshoot will see room temperature rise to set point + x degrees - too hot. Next, the thermostat will not switch the heater back on until the room temperature has fallen to set point - y degrees (hysteresis) and, again, thermal lag and overshoot wil see room temperature fall to set point - x. This swing around set point will make for an uncomfortable room/caravan.
What you *really* need is a controller which has a PID algorithm (Proportional, Integral & Derivative). This is a semi intelligent algorithm which looks at rate of change of temperature and cycles the heater accordingly to minimise undershoot and overshoot to almost nothing and produce a stable temperature. However it will cycle the heater rather more often than an on/off controller.
PID controllers have been around for many years (50?) and should be readily available and cheap these days. NB. A PID controller has to be "tuned" (learn) to its environment and I think most are self learning nowadays but ensure this is covered in the manual before buying.
Our Planer brand heater can operate continuesly OR via thermostat between 5 & 35c. I believe the later ones have an even better arrangement for temp control.
Aussie Paul.
-- Edited by aussie_paul on Monday 5th of March 2018 02:06:32 PM
Thanks everyone all great comments, and will give me plenty to consider. I see some on ebay are getting really cheap now $ 230. but I will now take a closer look at them as to what sort of temperature controls they have, and then see how much of a cheapskate I am going to be. I do know I don't want to be cold any more. Landy
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If buying another Diesel Heater I would look at the Belief Heater from Tassie, has 2 methods of controlling the heat, which to me gets over the problem as mentioned by Mike Harding above. Planar heaters may do a similar job.
From the Belief Website:
Heat output control and regulation on air heaters work in two ways
Temperature control In this mode the heater will sense the cold air input coming into the heater and will turn itself up or down depending on the position of the control switch. If the switch is turned down to low this will cause the burner in the heater to go out. When the temperature drops below the control switch setting temperature, the burner will reignite and heating will resume. As the heater requires the glow plug to start the burner flame, the glow plug ignition will draw around 10-12 amps (120w-144w) of current during start-up.
Heat output In this mode the positioning of the control switch regulates the heat output of the heater basically the same as a bar radiator. Using this mode does not turn the burner off but turns down the fuel supply and fan speed with the heater only drawing a run current of between 1.5 amps to 2 amps (18W-30W)
Other heaters on the market only use temperature control. In some cases careful positioning of the control switch is required so that the heater does not turn off. If this is not achieved the heater will draw 12 amps on start up for approx 2 minutes before going to its run current approx 2 amps (on high). This type of regulation is hard on batteries especially if only 1 battery is installed.
Our belief heaters can be set on both temperature regulation or heat output; we recommend setting them on heat output as this gives better battery life and step-less heat output from low to high. This switching is achieved by pushing the up and down arrows together on the control switch.
Landy, our diesel heater works as Peter describes. It is a 2 KW size and works well in a large van. 2kw is more than plenty, although there is a new size now of 2.2kw. I think I worked out that it costs us around 10 to 12 cents an hour to run depending on diesel cost. We usually have it set it on number 1 or 2. (low) The crowd in Tassie told us after running it on low for the night, to give it a burst on high for 20 minutes to burn off carbon deposits. The cost of a diesel heater is worth every cent if you are away from 240 v and the fan heater.
Joe
edit; just reread landy's question. Have had no problem at all with our Belief.
-- Edited by Farmhat on Monday 5th of March 2018 07:41:07 PM
Another thing to consider is, where are you going to install it?, the normal spot seems to be under the bed, or under the seating of the lounge. But things can go wrong, i.e. there's a water tank under and in the way etc. Instructions are on the net, and the fitting is pretty much universal. So climb under and over and plan. If you question the heat it puts out around the unit, let me tell you it gets very hot.
My installation ended up being quite complex, and ended up mounting it under the van. The diesel tank I mounted in the front boot.
Well it looks like 2kw will be plenty judging by your reply's especially as the new van will be a fair bit smaller than the old one. I won't be sure where to fit it until I get it home but I have taken the heat aspect on board. Thank you for all your reply's I have found them all a great help. Landy
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Ours is so efficient we donât notice the fuel going down even if we camp for weeks . Yea itâs connected to main tank . The fan varies with heat control on ours . The unit is under lounge intake behind drivers seat ( motorhome ) outlet/s are just before bed . It blows under bed and cabinets area depending where outlets are directed . I fitted two inlets as I found having one . Can block
Up easy with storage or things being stored infront of inlet .,
Hi Landy I bought a VVBK diesel heater for our van but ended up fitting it to our camper trailer it works a treat its only a 2 kw unit plenty big enough, when choosing we were told not to go for the 5 kw unit as it would be too big for our 24ft fifth wheeler as the unit will be running at an idle and will carbon up causing problems and requiring you to disassemble the unit to clean it out , dont want that.
It has a variable fan which regulates the set temp as well as the fuel rate is adjusted automatically, bought it direct from VVBK in China fantastic people to deal with .
Here is a link to their website with a list of things to consider about purchasing a diesel heater
When the power of Love becomes greater than the love of power the World will see peace ! 24ft Trailblazer 5th wheeler n 05 Patrol ute and Black Series Dominator camper trailer ( for the rough stuff)
Yep will keep you all updated its going to be a couple off months though Iana. thanks for the link Woody and Sue it will be part of the research. Landy
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Hi Landy, where on ebay did you see them for $230? I'd appreciate the link, thanks :)
I never wrote down the name at the time Circlec But there is a 5 klw Planer on there at the moment for $ 242 with free postage the seller is winwin2win I tried to get a link for you but I can't get it to work. Landy
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Hi again all. Just a line to let you all know I finally bought the diesel heater although still waiting for the new van.
I'm afraid in the end the cheap side of me won out and I bought one of the generic Chinese units the cost was $251.00 or there about after applying one of the Ebay discounts that includes a 10 ltr plastic tank, what I didn't relies at the time was i didn't come with an exhaust silencer so I would advise any body else to read the ads carefully as that will probably cost another $20.00 . It took a little bit of searching to find a 2 kw model as nearly all the cheap units are 5 kw and after doing a bench test and as others have already said on this thread I think 5 kw would be far to much. I have run this unit for 5 1/2 hours so far on a one liter plastic tank I had laying around and it is still close to half full so I expect it to prove very economical.
Landy
-- Edited by landy on Saturday 19th of May 2018 09:06:08 AM
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