Reply
 
Thread Tools Display Modes
 
Old 03-31-2014, 11:55 PM   #21
Mini-Skoolie
 
Join Date: Mar 2014
Posts: 32
Re: Hydronic Radiant Heating in a Bus

I have seen radiant heat supplyed to green houses through 1 inch pex and being heated by a manure/compost pile wich puts off quite a bit of heat sure but nothing like a hot water heater.....just speculating not trying to be argumentitive its hard to convey tone in type.
texasrednek is offline   Reply With Quote
Old 04-01-2014, 12:04 AM   #22
Bus Geek
 
Join Date: Aug 2011
Location: Stony Plain Alberta Canada
Posts: 2,937
Year: 1992
Coachwork: Bluebird
Chassis: TC2000 FE
Engine: 190hp 5.9 Cummins
Rated Cap: 72
Re: Hydronic Radiant Heating in a Bus

Quote:
Originally Posted by texasrednek
I have seen radiant heat supplyed to green houses through 1 inch pex and being heated by a manure/compost pile wich puts off quite a bit of heat sure but nothing like a hot water heater.....just speculating not trying to be argumentative its hard to convey tone in type.
Quite to opposite. I encourage others to think along, present challenges, and bring forth other idea's and solutions.

They way the pipes were looped, without the conventional bottle necks in the manifolds, may have played a big role in that greenhouse system being successful.

Nat
__________________
"Don't argue with stupid people. They will just drag you down to their level, and beat you up with experience."

Patently waiting for the apocalypses to level the playing field in this physiological game of life commonly known as Civilization
nat_ster is offline   Reply With Quote
Old 04-01-2014, 12:26 AM   #23
Mini-Skoolie
 
Join Date: Mar 2014
Posts: 32
Re: Hydronic Radiant Heating in a Bus

I was also thinking more about that green house. I realized a fairly large variable difference in application, the temps out side were in the 40's and 50's f. And only raised temps in the green house by a few degrees in early spring I wasn't thinking its going to be used to heat a living space to a comfortable level when its in the single digits. But hey I'm from Texas if I needed to heat my bus in the grips of winter I would light a candle!
texasrednek is offline   Reply With Quote
Old 02-24-2015, 11:44 AM   #24
Bus Geek
 
Join Date: Aug 2011
Location: Stony Plain Alberta Canada
Posts: 2,937
Year: 1992
Coachwork: Bluebird
Chassis: TC2000 FE
Engine: 190hp 5.9 Cummins
Rated Cap: 72
Quote:
Originally Posted by That Guy in Maine View Post
Hey guys,

I got some good answers in my thread about propane storage but I'm trying to figure out a bit more information on the typical usage for LP on board a bus. It's looking like I might get a coach right now and so there's plenty of under-bus storage for utilities like water tanks (especially since I won't have a black water tank), batteries, and propane tanks...but I need to budget space for a heating system which can be a bit more complicated.

I've tossed around the idea of using a few different systems and compiled some pros/cons of each...

Between wood heat, RV furnaces, electric heaters, and radiant heat I think that radiant is the best option. There are a few reasons, first of all it's quiet and works completely in the background, very little input is necessary from the inhabitant. The systems are generally regarded as being energy efficient, and the cost isn't too extreme from what I've found so far. On top of that it means that the floor will always be warm and I'll be able to walk around in the dead of winter in my bare feet. When we put an addition into our current home the master bathroom got radiant floor heat and it's so nice in the winter to not have to put socks/slippers on to go to the bathroom.

Anyway, for now I want to plan for radiant heating. If anybody has experience with this type of system in a conversion I'd love to hear it!

I have chosen to run a closed loop system, this means one hot water heater for the floor and one for domestic use. Because I'm doing a closed loop I can also use the radiant heat to heat the diesel engine in the winter which will be of great benefit on ski trips that take me into the mountains in the dead of winter.

Finding a properly sized water heater is proving to be difficult. First of all I am not really sure how to calculate the BTUs required for the space. I've googled "BTU calculator" and plugged the same information into a few calculators and gotten different numbers ranging from ~8,000 BTU all the way up to ~75,000 BTU and some in the middle.

So assuming the high end of that BTU rating is the accurate one, do I just look for a water heater with a 75,000 BTU output rating? Would that mean it's on all the time? Should I be looking for a 150,000 BTU rating heater? I'm not really familiar with all this heating stuff.

The plan is to use rigid foam underneath the floor that the radiant is in, and blown in insulation in the sides and ceiling of the bus. I also plan to insulate the accessory bays under the bus that house the water tanks so they don't freeze in the winter.

Then my other question is about gas consumption, how much should I be expecting to consume with a hot water heater tasked with heating via radiant heat?

Sorry for so many questions but heating is one place I'm a bit overwhelmed...the bus will surely be used on days where it gets to -15F or colder at night and barely above 0F some days. Last night it was below -20F here but that's probably the coldest night of the year so far.

Any help would be appreciated!
With the insulating method you mentioned, A 30 to 40,000 BTU low efficiency propane hot water heater is all you need.

The cabin I built uses this system, and has worked great for the last three winters.
Cabin build for Old Timer - Pirate4x4.Com : 4x4 and Off-Road Forum

Nat
__________________
"Don't argue with stupid people. They will just drag you down to their level, and beat you up with experience."

Patently waiting for the apocalypses to level the playing field in this physiological game of life commonly known as Civilization
nat_ster is offline   Reply With Quote
Old 02-24-2015, 07:09 PM   #25
Bus Crazy
 
somewhereinusa's Avatar
 
Join Date: Nov 2010
Location: Andrews,Indiana
Posts: 1,636
Year: 1991
Coachwork: Bluebird
Chassis: AARE
Engine: 3116 Cat 250hp
Rated Cap: Her, me and Molly
The boiler I use is rated at 10,000 btu, runs on diesel fuel out of the fuel tank. I did the floor basically like you described. It was -5 the other day and got so warm I had to start turning things down ( I haven't got all of the thermostats in yet). Once it's warm it just kinda idles keeping things warm.
There are pictures on my build thread and at SomewhereinUSA

Dick
somewhereinusa is offline   Reply With Quote
Old 02-24-2015, 11:56 PM   #26
Mini-Skoolie
 
Join Date: Jan 2014
Posts: 27
OK, so I'm trying to figure out what I'll need to construct a full system. I'm planning to build a system similar to what somewhereinusa uses in his bus. Here's his schematic: http://www.somewhereinusa.x10.mx/hydronic%20heat.pdf

The plan is to have four (possibly five in the future) zones.

Zone 1: Driver area, probably won't have any PEX heating but will have the original blowers and an aftermarket kickspace heater like this: UC101B - Cadet UC101B - Perfectoe Black Under-Cabinet Heater, 1000 Watt (120V) mounted behind the driver seat facing forward.
Zone 2: Lounge/work area, PEX tubing throughout with one kickspace heater under the desk.
Zone 3: Bathroom, no kickspace heater, just PEX tubing.
Zone 4. Bedroom, one kickspace and PEX tubing throughout.

The possible 5th zone would be in the enclosed trailer behind the bus, probably using a one or two kickspace heaters and would only be turned on to do stuff like ski tuning in the winter.

The hot water heater will also be able to feed the domestic hot water and engine coolant via two heat exchanges, I could use some help selecting which exchanges to use though, would something like this be enough for both uses? BP400-10LP - Bell & Gossett BP400-10LP - 60,000 BTU/Hr Low Pressure BPX Brazed Plate Heat Exchanger

So for each zone I would need a valve and thermostat, correct? I also need a control board to manage the entire system. I also need an expansion tank.

Am I missing anything? Any product suggestions?
That Guy in Maine is offline   Reply With Quote
Old 02-25-2015, 09:16 AM   #27
Bus Crazy
 
somewhereinusa's Avatar
 
Join Date: Nov 2010
Location: Andrews,Indiana
Posts: 1,636
Year: 1991
Coachwork: Bluebird
Chassis: AARE
Engine: 3116 Cat 250hp
Rated Cap: Her, me and Molly
Quote:
Originally Posted by That Guy in Maine View Post
OK, so I'm trying to figure out what I'll need to construct a full system. I'm planning to build a system similar to what somewhereinusa uses in his bus. Here's his schematic: http://www.somewhereinusa.x10.mx/hydronic%20heat.pdf

The plan is to have four (possibly five in the future) zones.

Zone 1: Driver area, probably won't have any PEX heating but will have the original blowers and an aftermarket kickspace heater like this: UC101B - Cadet UC101B - Perfectoe Black Under-Cabinet Heater, 1000 Watt (120V) mounted behind the driver seat facing forward.
You can build your own much cheaper using an automotive heater core and muffin fans.I'll take some pictures of the one I built.The rest of mine are commercial that I got a good deal on. The one I built puts out more heat.
Zone 2: Lounge/work area, PEX tubing throughout with one kickspace heater under the desk.
Zone 3: Bathroom, no kickspace heater, just PEX tubing.
Zone 4. Bedroom, one kickspace and PEX tubing throughout.
As it turns out, I probably don't need all of the kickspace heaters. They do make it nice though for quicker initial heat up. I might not have enough in the front, the flat nose buses tend to be a bit cold while driving.

The possible 5th zone would be in the enclosed trailer behind the bus, probably using a one or two kickspace heaters and would only be turned on to do stuff like ski tuning in the winter.
I think this would be a problem area. You would need to make some provision for unhooking which wouldn't be a big deal but, it would introduce air which IS a big deal. It takes a lot of bleeding to get rid of the air and it is VERY inefficient when there is air. You would also need to insulate the tubing so you don't loose heat between bus and trailer. I would think some sort of space heater (electric,kerosene?) would be better.

The hot water heater will also be able to feed the domestic hot water and engine coolant via two heat exchanges, I could use some help selecting which exchanges to use though, would something like this be enough for both uses? BP400-10LP - Bell & Gossett BP400-10LP - 60,000 BTU/Hr Low Pressure BPX Brazed Plate Heat Exchanger
That looks like the one I used except it is a 40 plate,146,000 BTU,I got it much cheaper on ebay. If you use a marine water heater similar to this Seaward S600 Marine Electric Water Heater with Rear Heat Exchanger it has a heat exchanger built in.

So for each zone I would need a valve and thermostat, correct? I also need a control board to manage the entire system. See my comments below.
I also need an expansion tank.
I didn't do it that way. My boiler has a pump in it. I control the zones with a pump on each loop. I used four of these Webasto Espar Hella Water Coolant Pump Heater or Hydronic DC Boat RV | eBay connected to the thermostat using a relay. These pumps are the same as built into the boiler. The fans for the kick space heaters just have a toggle switch. I used a temp switch (102F) mounted to the incoming water line to the heater. When the t-stat turns off the water pump the water cools enough to turn off the fan. It also keeps from blowing cold air until the water is warm enough.

Am I missing anything? Any product suggestions?

I miss remembered, my boiler is a Hydronic 10,putting out
32,400 BTU/hr on high. Link to manual http://www.esparofmichigan.com/cmsAd...Hydronic10.pdf

This is just my opinion. I think that some sort of system made to be used as a heat source for the water would be better. I can't say for sure but I would think even more economical to run. The one I have has a control module complete with 7 day timer if needed. And while it is on all of the time when it is on, it cycles between high and low to keep the water at an even temp. Even in below 0 temps it stays on low much of the time. I'm also not a big fan of propane, not particularly because I think it more dangerous, I just think it a pain in the A**.


Hope this helps
Dick
somewhereinusa is offline   Reply With Quote
Old 02-25-2015, 10:22 AM   #28
Bus Geek
 
Join Date: Aug 2011
Location: Stony Plain Alberta Canada
Posts: 2,937
Year: 1992
Coachwork: Bluebird
Chassis: TC2000 FE
Engine: 190hp 5.9 Cummins
Rated Cap: 72
We need to know where you live to really have a grasp on your needs.

Like somewhereinusa I use a pump with a thermostat wired into each loop. When the thermostat calls for heat, it simply turns the pump on, starting the flow of hot water under the floor.

What you use for a boiler / water heater will depend on your budget.

At the lowest end of the scale is the 40 ga 30,000 to 40,000 BTU propane water heaters. Cost around $250 to $400.

Next would be a boiler with the settings that somewhereinusa mentioned. Cost starting around $2500, and hard to get one with a small enough heat output to keep it from short cycling.

Or last would be a high efficiency 40 gal, 75,000 BTU water heater that is made to use as a space heater / potable water heater. They have two sets of ports, some come with a back up electric element.
Cost Starting at $3000

One more thing I want to mention is this.
In cold climates, Hot water lines should be run under your entire interior floor space. This means under cabinets, closets, ect. This prevents cold from creeping in from the sides, and keeps the entire interior a even temp.

This really makes it more simple to install. My bus will have 7 runs of half inch line from the front, all the way to the back. This means I will have 14 lines under my feet, one every 4 inches. All lines will have their connections at the back of the bus, where they tie into the manifold that connects them to the 1 inch main feed line coming from the boiler.

I want to emphasize the need to keep the system restrictions to a minimum.
For instance, I could run all my loops as one long line. 7 x 60 feet = That's 420 feet. Max run for half inch line is 200 to 300 feet depending. We could use a bigger pump, but that is a bad idea. By manifolding the loops, we can use a pump one tenth of the size without loosing flow. Smaller pump = cheaper and more efficient to run.

I'm still thinking of custom making my boiler out of stainless, low profile to fit under a bus, with two built in heat exchangers, and 6, one inch ports for electric heating elements. Sadly there is nothing on the market like this for under $3500, and all commercially available units are to tall to fit under a bus.
This would seriously simplify installing the hydronic heating in a bus.

If I do make my own boiler, I may make a few more to sell to fellow skoolies. There would be no profit for me, just helping out fellow members.

Quote:
Originally Posted by somewhereinusa View Post
The one I have has a control module complete with 7 day timer if needed. And while it is on all of the time when it is on, it cycles between high and low to keep the water at an even temp. Even in below 0 temps it stays on low much of the time. I'm also not a big fan of propane, not particularly because I think it more dangerous, I just think it a pain in the A**.
The $400 propane hot water heater that heats the 16 x 24 cabin only cycles 25% of the time when it's -25C or lower. We keep the tank temp setting low, and increase it as the temp get's colder outside. This keeps our efficiency up, as the hotter you try to heat the water, the less efficient a propane / gas boiler gets.

The water heater is installed in a sealed closet made specifically for the water heater. The closet was built with minimum clearances to combustibles and vented to the outside.

Nat
__________________
"Don't argue with stupid people. They will just drag you down to their level, and beat you up with experience."

Patently waiting for the apocalypses to level the playing field in this physiological game of life commonly known as Civilization
nat_ster is offline   Reply With Quote
Old 02-25-2015, 07:24 PM   #29
Bus Crazy
 
somewhereinusa's Avatar
 
Join Date: Nov 2010
Location: Andrews,Indiana
Posts: 1,636
Year: 1991
Coachwork: Bluebird
Chassis: AARE
Engine: 3116 Cat 250hp
Rated Cap: Her, me and Molly
Here's a couple pictures of the heater I built.





Basically sandwiched the core then built a box. I mounted the fans so they would suck through the core. They seem to move more air that way. Mounting would depend on how your core is built. This was a nice copper one that someone gave me.
somewhereinusa is offline   Reply With Quote
Old 02-25-2015, 10:41 PM   #30
Mini-Skoolie
 
Join Date: Jan 2014
Posts: 27
Quote:
Originally Posted by somewhereinusa View Post
-snip-
Hope this helps
Dick
Very good information there, thank you.

Quote:
Originally Posted by nat_ster View Post
We need to know where you live to really have a grasp on your needs.

One more thing I want to mention is this.
In cold climates, Hot water lines should be run under your entire interior floor space. This means under cabinets, closets, ect. This prevents cold from creeping in from the sides, and keeps the entire interior a even temp.

The $400 propane hot water heater that heats the 16 x 24 cabin only cycles 25% of the time when it's -25C or lower. We keep the tank temp setting low, and increase it as the temp get's colder outside. This keeps our efficiency up, as the hotter you try to heat the water, the less efficient a propane / gas boiler gets.

The water heater is installed in a sealed closet made specifically for the water heater. The closet was built with minimum clearances to combustibles and vented to the outside.

Nat
I live in the White Mountains of NH, this is how a typical February goes here (this is this years):

Most days get above 10 degrees, some nights get as cold as -20F.

I plan to run the radiant through the entire floor, but I've heard that it would be smart to not loop under your refrigerator which makes sense to me so I'll probably pre-plan for that.

As for water heaters, I think a tankless unit makes the most sense for me. I'm not too worried about spending $25 or $50 a month more than if I had a boiler or something more efficient. I just want something that will work and not take up a lot of space.

This may be a stupid question but if I get a hot water heater rated for 150,000 BTU is it going to work for such a small application? Or what is a good way to find a smaller sized water heater? I want something that's powered off of propane preferably.

Thanks again guys, this is a huge help!
That Guy in Maine is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Radiant Floor Heating......feedback requested Shawn C Heating, Cooling and Appliances 14 12-30-2012 11:18 AM
Propane Heating - Radiant vs Blue Flame Stuff Heating, Cooling and Appliances 12 11-08-2012 05:19 PM
Radiant Floor Heating Reference zim Heating, Cooling and Appliances 16 01-08-2011 02:41 PM
Radiant Floor Heating oldog12 Conversion General Discussions 8 08-24-2006 02:05 PM
Modify stock heating system or seak alt heating? phillbus914 Conversion General Discussions 4 09-14-2005 06:14 PM

» Virginia Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 11:47 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.