Radiant heat vs Forced air

[bigskypc50]

Greetings, fighting with my forced air RV style furnace, as I sit on the couch the furnace will run for 5 mins and stay off for 15/20 mins and in the mean time as soon as the furnace shuts off I can feel the cold taking over.

Would something like a Wave 6 heater going all the time help level out the temp swings and just abandon the forced air unit? The bus is poorly insulated, still has windows and stock celling.

In a poorly insulated metal can is radiant heat better than forced air?

[mmoore6856]

we are staying with fa as i like the filter and if it gets cold inside radiant takes a while to get back warm.. have you considered putting insulation on the outside of the roof?

[Sehnsucht]

I would say that insulation is the answer because it doesn't matter what your heating source it's going to have to run non-stop since the heat leaks out of the bus as fast as it's being produced.

[kazetsukai]

Originally Posted by bigskypc50

In a poorly insulated metal can is radiant heat better than forced air?

In our research into yurts and winter, wood stoves work well, forced air does not. This is because the stove is a giant radiant heat source and the insulation is designed to reflect the radiant heat back into the living space.



Idk if you're in the middle of your build or near the end- if you want comfort rip it all up and insulate. Our ceiling is better insulated than our walls, I think. There's 1.5" foam, filled the gaps with great stuff and covered it all with reflectix. In the walls there's 2.5" of the pink stuff you see in houses. I feel the reflectix added quite a bit when it comes to radiant heating, and kind of sealed everything up.

[magnakansas]

IF, If I understood conversations and articles about home heating. The current thought is a smaller heating system running at very low levels all the time. It works like this..... the energy used to heat the parts, like ductwork, vent openings, heater box and such, it is better to keep them warm all the time, instead of heating up, cooling down, heating up, cooling down....

In my house in 1960, a 120,000 btu furnace starts up, heats the monster for about ten minutes then turns off until the thermostat says "fire away" once again...... recommended replacement furnace would be a two or three stage burner and more efficient heater box also... so one stage would only be around 40,000 btu or so, 2nd would be 60 or 70, and thrid stage would be around 90,000 btu ..... so you see a low level would always be on.

now if I use the same idea on my bus.... I have a diesel fired engine coolant heater and I have three inside heaters, one in the rear, one about a foot behind the driver and one on the fire wall..... My heater burns about .6 gallons of diesel an hour and is supposed to be good for up to 90,000 btu.

all of the heaters have fans, I do not have to have the fans running....

The coolant heater has its own water pump. I can shut off connection to the engine if I want, but! the coolant expansion tank is used by the engine and the coolant heater system. Important detail. I can have radiant heat with the noise of big fans going on any or all of the heaters while parked.

The coolant heater keeps coolant warm and that cycles on and off but the coolant in the heaters kind of levels out temperature fluctuations.

I have seen and heard of some people using 12 volt computer fans to keep heat flowing with less noise than the usual big fans used on bus heaters.

They make smaller coolant heaters than the big monster I have and those use less diesel per hour. You could set them up so that they are not connected to the engine cooling system. they even have remotes and timers for temperature control....

I hunted down a big Webasto brand heater. this kind of system is also used on boats. And you can they have heat exchangers for heating potable water.. shower water? from the engine coolant system too.

william

[bigskypc50]

Long rambling post ahead!

Thanks guys for the awesome feedback really appreciate it. The Forced Air furnace is 42K BTU and it's really only heating the front 20ft of the bus. The Tstat is about 15ft away from the heater and the furnace is under the couch I sit on. The furnace will warm it from 35 degrees to a nice 55 in maybe 15-20mins.

MMOORE, yes that would work awesome but for now the bus still needs to mobile and drivable future plans include a carport and maybe laying fiber glass across the top of the bus.

kazetsukai, sadly the build it totally done
I have thick thermo curtains over the side windows and the walls under the windows and floors all have 1.5" ridge foam, plus the bus still has the factory 2" batt everywhere and just mini-blinds over the front windshields. Guys are likely right I need some kind of insulation over the front windshield.

After reading all your post's, I am even more sure adding a small wave 3 or 6 heater and let it run on low would help comp for the heat loss. Funny enough when plugged in to grid power a forced air space heater (DR HEATER) in the front and oil filled in the rear keep it plenty steady and warm.