Added Auxiliary Heater - now there's no heat!?

[roadtripcrazed]

I recently installed an auxiliary heater in the canopy of my 2010 Nissan Frontier. This is a simple coolant-type heater which is tied into the heater hose in the engine bay. As long as the engine is running at ~1800rpm or higher, there is excellent heat produced in both the cab and canopy. Unfortunately, when the engine idles there is not sufficient coolant flow to produce heat at either locations.

When installing the auxiliary unit, I was sure to include a bypass so I can isolate the original system from the additions. By using the bypass I get solid heat to the cab at all times - idle or high rpm. It is only when I add in the new system that I get a decrease in performance.

I assume this is due to the volume of coolant that the engine needs to circulate. Or is this caused by something else? Air lock? Restriction?

Any thoughts are appreciated. I have attached a diagram of the coolant system to assist those with questions.

Thank you!

 

[Jeep]

Probably a little too much coolant for the water pump to move. We install electric booster pumps when there is over 10' of heater hose, works great.

 

[roadtripcrazed]

Probably a little too much coolant for the water pump to move. We install electric booster pumps when there is over 10' of heater hose, works great.

More information on the electric booster pump would be greatly appreciated.

 

[Tony LEE]

One problem that arises - especially with diesel engines - is that they are so efficient that there is just not much waste heat to spare for extra cabin heating. Barely enough for the drivers cab but not enough to heat anything else - hence the use of diesel auxiliary heaters even when driving on the road.

 

[Phreak480]

just a thought, do you really need heat in both locations all the time. could you put some additional valving in and circulate only to the canopy heater so you could get better heat there when you need it?

 

[roadtripcrazed]

One problem that arises - especially with diesel engines - is that they are so efficient that there is just not much waste heat to spare for extra cabin heating. Barely enough for the drivers cab but not enough to heat anything else - hence the use of diesel auxiliary heaters even when driving on the road.

This is a gasoline engine and there is no issue at normal driving speeds. I am only experiencing issue when idling.

 

[roadtripcrazed]

just a thought, do you really need heat in both locations all the time. could you put some additional valving in and circulate only to the canopy heater so you could get better heat there when you need it?

I do need to heat both at the same time because our dog travels back there in the winter. We live in Canada. :elkgrin: Heat is not optional!

The idling issue also means that we can not start the truck to let the cab warm up before hitting the road. Yes, the engine warms up but the cab is still an ice-chest!

-=Doug

 

[Wyowanderer]

Probably a little too much coolant for the water pump to move. We install electric booster pumps when there is over 10' of heater hose, works great.

Yup, on school buses they install pumps to help coolant flow to the rear seat heaters, otherwise they won't work.

Jabsco makes one, sold by Grainger as PN 3PET5, selling for $245.50 list. It has a 3/4" inlet and outlet, so you'd need to adapt it down.
http://www.grainger.com/Grainger/ww...uery=3PET5&op=search&Ntt=3PET5&N=0&sst=subset

 

[truck mechanic]

or if your into junk yard stuff, get one out of a mercedes oil burner. i got one for $10 in the rebulic of ma.
just my .02
Paul