Electric heating

[Richard Dodd]

Hi I have just bought a eldis autoquest 115, I put the electric heating on to try and found one end is blowing hot but the other end is blowing cold. I'm new to motorhomeing so any information would be greatly appreciated, it doesn't say anything in the book many thanks Richard 

[Derek Uzzell]

I believe your Elddis 115 motorhome is a 2013 model that you obtained in late-2023.

This Elddis Owners Handbook (supposedly!) relates to 2013 Autoquest models 

https://www.manualslib.com/manual/1332799/Elddis-Autoquest-2013.html#manual

and Page 9-13 indicates that the space-heater was a Whale SH2012.

This is a relatively straightforward blown-air heater (picture below) that can operate on gas or via a 230V mains power-supply and is designed to be fitted beneath a motorhome's floor.

 

The Handbook describes mains-electrics operation as follows

I don't know how Elddis would have installed this blown-air heater in your motorhome, but the basic principle involves the heater sucking in air from an intake within the motorhome's habitation area, heating that air and then blowing it back into the habitation area through air-outlets. I'm guessing from your enquiry that your 115 has two outlets and the air coming out of one outlet is hot, but only cold air is coming out of the other outlet.

It needs saying that many motorhome builders are notoriously poor at installing a blown-air heating system that will deliver warmed air efficiently everywhere in the habitation area. So, if you are running your heater on the low power electric setting and warm air comes from one outlet, but cold from the other, it probably means that the air ducting between the heater and the 1st (hot) outlet is very short and the air ducting between the heater and the 2nd (cold) outlet is very long. (Fortunately, that some air is emerging from both outlets means that the ductings leading to those outlets are connected to the heater.)

If your air-heater works OK on gas, I suggest you try running the heater at its maximum electric setting to see if that improves matters. Or you could try closing off the outlet that's producing hot air to check if hot air then emerges from the other outlet.

The following comments relate to this type of heater fitted to a small 2 berth Elddis caravan.

I'm not sure if the unit would be powerful enough to heat a large caravan where the ducting has to travel some distance to the rear of the caravan, as well as heating the rear bathroom at the same time. Our rear bathroom is always a lot cooler than the main lounge if we keep the connecting door closed when the heating is on, yet the air vents and pipework are the same diameter as in the lounge area. If we want a shower on a chilly day early or late season we always leave the bathroom door open to allow the heat from the main area in to warm up the bathroom a bit more before we go in to undress.

[breakaleg]

My 2015 115 had the same hater and I asked the dealer the same question,

It does felt like it is blowing cold air but in fact it is sucking it in, easiest way to tell is to let go of a paper handkerchief in front of it and iff it is sucking in it will get drawn towards it, if not, blown away.

Pete

[Derek Uzzell]

If the temperature difference were due to the heater's air-intake being mistaken for an air-outlet, then surely this would be true when the heater was running on gas, not (apparently) just on electricity?

On the other hand....

https://www.motorhomefun.co.uk/forum/threads/eldis-majestic-115-weird-blown-air-heating.181515/

[stevec176]

Have you tried blocking the outlet where the hot air comes out and see if hot air comes out of the other outlet. Can you trace the ducting to make sure there's no holes and connections are tight. 

[Seth77]

Your motorhome's heating issue might be due to uneven airflow caused by differences in duct length; try adjusting settings or checking duct connections for a solution.

[Derek Uzzell]

No, the phenomenon Richard referred to in his posting is (almost certainly) explained in the follow-up by breakaleg and in the MHFun thread I provided a link to.

The interior layout of a 2013 Autoquest is shown in the following drawing and the Whale space-heater was mounted under the floor of the offside locker (arrowed in green)

The MHFun thread includes this photo of the installation 

The beige-coloured air-trunk leads forwards to a fitting (arrowed in green) directly behind the driver's seat, while the black air-trunk (arrowed in red) leads backwards to similar/identical fittings in the rear of the motorhome. The beige air-trunk connects to the heater's air INLET, so cool air is sucked IN through the green-arrowed fitting. The black air-trunk (red-arrowed) connects to the heater's air OUTLET, so WARMED air is blown through that trunk and into the rear part of the motorhome's habitation area.

WHALE fittings are advertised here

https://autocraftmotorcaravans.co.uk/product-category/blow-air-heaters-water-heaters/whale-products-blow-air-heaters-water-heaters/

and I'm guessing that Elddis chose to use identical 'fixed' vents at the ends of the inlet and outlet air-trunks, thus leading to confusion for the unwary owner who (not too surprisingly) might mistake the inlet-fitting behind the driver's seat for a warm-air outlet.

Modifying the air-trunking to convert the cool-air inlet to a warm-air outlet should be quite simple (see MHFun thread). Adjusting the heat output using 'flapped' vents risks overheating the heater, which may be why Elddis chose not to.

[david lloyd]

Designers eh? I was going to suggest the easiest resolution may be to tee off the black warm air duct and fix this to a (flapped) outlet at or near the base of the offside sofa facing into the aisle. Certainly this is the most oft seen place for a heater outlet on this layout. But, I now see that the bed base is constructed in such a way that the entire front lifts up with the bed base to access inside the locker beneath - which makes it easier to access whatever is in the locker but the traditional drop down flap would have allowed a heater outlet to one side of it.

David

[Derek Uzzell]

With hindsight, I'm not 100% sure that Richard's 2013 Autoquest has the Whale "Duo" underfloor gas/electric heater shown in the MotorHomeFun photos, but it still seems likely (with Richard's 115) that Elddis installed the heater's air-intake behind the driver's seat.

In the case of the MHFun thread, as well as the settee's top and front hinging upwards, the whole thing pulls out horizontally when the double-bed arrangement is selected. (photo below)

Converting the heater's cool-air intake into a warm-air outlet (and letting the heater take its cool air from within the settee base) is probably the simplest approach, but an alternative would be to put a grille into the settee's front and fit a separate warm-air outlet directly behind the grille. Then, when the settee's front was down in its 'normal' position, warm air would emerge through the grille and, when the front was pulled out horizontally to make up the double bed, warm air would exit directly from the warm-air outlet and under the bed. This should be more efficient than having a warm-air outlet behind the driver's seat and, although a small amount of woodworking surgery would be required to fit the grille, tee-ing into the the existing black air-ducting would be very easy. And, if the new warm-air outlet were the directional (butterfly) type, the amount of air coming out could be controlled without risking the heater over-heating.

 The air-heating installation of my bought-in-Germany 2005 Hobby motorhome had a major build fault, so that (literally) no warm air was being delivered to the front part of the habitation area. And my 2015 Rapido's air-heating installation completely ignored Truma's advice, so that 80% of the hot air came out of a single outlet on the side of the island bed. I DIY rejigged/rebuilt the Hobby's system and it was brilliantly effective afterwards. However, as most of the Rapido's air-ducting was under the floor and unreachable, the best I could do was make improvements.