| Author |
Message |
Brian (Bigbusguy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 3:12 am: | |
I would like to know how you that tied into the bus water lines to supply to heaters. Im using 3 small forced air heaters using the bus coolent they have 3/4 pipe openings and the bus has 1 inch lines run to the front.
I plan on one for the bed room one in the living room area and 1 for the drivers area and defroster.
What I was thinking if I run the water to bed room on first and out to the ones up front it would slow the flow , Or should I Tee in to the line and take some of the water for it and let the rest go the the front for the other 2 ?
I was hoping to not have to use coolent pumps.
I would like to use a hot water heater heat exchanger also.
I can change all the piping the bus had a run new ones to make this work when I replace the floor .
I would like to know what others have thats works good and have it installed in there bus and how you done it and if you have any drawings of the piping.
Thanks
Brian 4905 Klamath Falls Oregon |
FAST FRED
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 5:38 am: | |
I was hoping to not have to use coolent pumps.
With box heaters the inlet may be 3/4 but like any radiator the passages inside are much smaller, so PLAN on a circ pump , if you want reasonable heat.
Perhaps with 1 1/4 baseboard you might get away with a heat loop or two and no pump.
We use the std drivers defroster/heater and a single 40,000 btu box heater installed where it will suck air from the old vent for the penlum .
Since all those holes were enough for make up air in the orig system , there seems no pressure drop .
Yes we use the orig circ pump , but have rewired so the drivers blowers can come on , with out the circ pump , for summer ventilation.
A small sophistication is the use of a cable operated water valve , so the pax can change the heater output .
Second we find when camping by using the circ pump , and blower we can "steal" heat from the just shut down engine for 3 or 4 hours.
"Free heat"
In summer the box heater can be used as an outside air blower, for fresh air.
BEWARE , some box heaters have louder fans than others, that makes a big comfort difference while stopped.
FAST FRED |
t gojenola
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 7:19 am: | |
I have the big espar coolant heater in my 4106 and the heater has its own circulating pump. I have baseboard heat plus the front heater & defroster in the circulating system. I wired it so I can run the coolant pump independent from the heater. Without running the pump I find that very little heat reaches the defroster. But this is because the marine water heater is teed into the lines and probably forms the path of least resistance. It works great this way. Engine heat keeps the coach comfy down to about 20 without firing the espar. Without the pump running, it stays intolerably cold inside.
tg |
Geoff (Geoff)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 7:38 am: | |
I tied into the existing heating system (driver's heat and defrost copper lines) in my RTS with 2 heater boxes and a hot water heat exchanger (plus Webasto) but I did it in "parallel", not in series. I get good circulation and the heat is distributed better than if everything was hooked up in series.
--Geoff
'82 RTS CA |
Stephen Fessenden (Sffess)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 11:32 am: | |
You probably will not need coolant pumps when the engine is running. Mercedes has used an auxillary coolant pump in for the heater in many of its cars. If the coolant pump fails it takes longer for the heat to start and there is a little less capacity, but it still works. The purpose of the auxillary pump is to make heat instantly available. |
mel 4104
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 11:54 am: | |
for those of you that have gm,s there is a spot on the top of the rad for mounting a cir pump, iand in the book it will show how it is installed. also the gm transits have that pump mounted at the inside under the small seat if front of the big rear on on the driver side. they are the same pump that mounts on the top of the rad. these pumps will move a lot of water in a hurray as the force all the hot water for the heating of a 40 ft transit. and there are a lot of old transits around as i just scraped 25 the sad part was the had to be crushed and not resold for motor homes. |
Jim-Bob (Pd41044039)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 7:12 pm: | |
Hey Mel, will you be getting more?
Jim-Bob |
Buswarrior (Buswarrior)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 8:19 pm: | |
Hello Brian.
If you plumb them in in parallel, it gives you the opportunity to regulate the coolant flow at each heater. You may find you have too much heat under certain conditions and want to shut some of it off, or you may want to change your thermostat strategy and regulate the coolant flow instead of the blower fan. Plumbed in series, you won't have the kind of control you might like.
It would also allow you to choose to keep just a part of the coach warm, for instance, the bedroom at night, and not spend the money to keep the whole coach warm overnight. This is more of a concern if you are spending a lot of time living in the coach. Weekenders do not have to concern themselves as much with cost efficient operation.
Have you given thought to how you will evacuate an air lock at each of your heater cores? The heater cores end up the highest point and collect the air, with no way to get it out. Enough air, and the water won't flow. Accumulators are available from those areas of the continent where hot water radiant heating is used.
And you will thank yourself later if you install shut off valves to each device, in all your lines, feed and return. Otherwise, you have to drain the whole system (and fill it again through that nasty little door) to make repairs or upgrades. And you can isolate leaks and continue your trip without losing too much functionality. When something has sprung a leak, the cost of a few extra valves will be immediately worth every penny!!!
happy coaching!
buswarrior |
Jon W.
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 8:35 pm: | |
All of what is being discussed has been resolved and put into use on various bus conversions.
I have one that has four auxilliary heaters in addition to the bus over the road heat and AC. In addition engine coolant is used to heat the hot water tank. That bus has a circulating pump that I have only used once immediately after a coolant change to purge some air. Otherwise it circulates whenever the engine runs. Just do not ask me how.
The auxilliary heat exchangers are operated by on-off switches located at various point throughout the bus. There is no thermostatic control, so the system is either on or off.
On my other coach it has the Webasto heater tied in with the system and it has its own circulating pump. The logic there is that if you do not wish to use the Webasto to circulate hot water through the engine to keep it warm, you can turn that portion off via a valve and the hot water heated via the Webasto will circulate through just the in-coach heat exchangers.
The same heat exchangers will heat the coach without the bus over the road heat and AC coming into play just by energizing the Webasto. The Webasto will not fire unless the water falls below 160, so normal engine temps will allow the heat exchangers and their fans to function.
For engine heat to be used however the engine heat valve has to be open in the Webasto system.
The heat exchanger blowers are controlled via thermostats located throughout the coach.
Neither system is sophisticated or complex. We have used the auxilliary heating on both coaches while running down the road rather than running the bus system because we can better control the heat in various areas of the coach to suit what we prefer. |
John that newguy
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 8:39 pm: | |
Hmmm.....
Using the engine coolant to heat the water inside a water tank,
and using -that- water to run through the heaters (with a circulator
pump) would solve the problem of air locks, engine coolant
leaks, etc.
In fact, it would be easier to heat two hot water tanks using
the engine coolant, one for hot water and one for the heating
system. And.... If both hot water tanks can also utilize 110v
or propane (as in RV type?) hot water and heating problems
would all be solved.
Just another idle thought.... |
Stephen Fessenden (Sffess)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 10:11 pm: | |
John, if you do that you are limited by the heat exchanger you use. Be sure to use a big one for heat. A small one is OK for hot water because yo have half an hour or more to heat 10 gallons. My bus has had NAPA yellow stripe 3/4" heater hose (same as Gates Green Stripe) for 23 years with no problems connected to 7 individual loops for heating and hot water. There is a tank for accumulating hot water for heat. All is connected directly to the engine coolant with shut off valves to the engine for service and emergencies. The engine to acumulator tank loop looks like 1 1/4" copper, so note that it is bigger than the individual loops.
Also, may I mention again, LINE THERMOSTATS. They can handle up to 15 amps per circuit and voltages up to 240 volts. Mine work by activating fully enclosed microswitches, which are replaceable. I have a line thermostat with two circuits at each zone. One circuit controls the hydronic heat system at 24 volts (12 volts for some of us) and the other controls the 115 volt electric baseboard and wall heaters. There are 6 of each. Each individual 115 volt heater can be turned off from a main control panel. The hydronic system is turned on with one switch for all units and then activated by the thermostats. If I am driving, all work on engine heat. If I am stopped I turn on the Espar and waste half or more of the heat from it. It should have exhasted through a 4 tube through the center of the acumulator tank and the hot water heater, like an Aqua Hot.
When you are wiring your thermostats, and for all wiring for that matter, remember to leave at least 6 inch tails to the device, so that connections can be reached for easy maintenance. They did my thermostats and then put up the wall covering behind them obviously and they cannot be pulled away from the wall far enough to change thermostats. Dumb.
MAIN POINTS:
You have the choice of LINE THERMOSTATS that will work on full current and high voltage and need no relays. They are available with more than one circuit per thermostat.
LEAVE ENOUGH WIRE to pull out thermostats, outlets, switches etc to work on them or change them. I guess the same would go for hose. Leave an extra foot or so if you can for working room. |
Clint Hunter
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 07, 2005 - 11:37 pm: | |
When tee-ing into a constant presure system (especially with no pump) use Y's instead of tees, oriented with the flow entering at the base of the Y and you will reduce turbulence and increase flow rate substanially. |
Brian (Bigbusguy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, January 08, 2005 - 12:27 am: | |
Thanks every one for some good info, But what is a LINE THERMOSTAT ?
I guess Im lucky all my heaters have bleeder screws to let out air.
Brian 4905 Klamath Falls Oregon |
skoolbusut
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, January 08, 2005 - 1:45 am: | |
...Line "voltage" Thermostats I think is what he is saying.
mark |
Stephen Fessenden (Sffess)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, January 08, 2005 - 8:34 am: | |
LINE THERMOSTAT is the name given to a type of thermostat that can handle the full load of a heater or air conditioner at the thermostat rather than dealing with a low voltage thermostat and relays. LINE THERMOSTAT is what you would ask for when looking for one in a store or doing a search on the internet. Also called LINE VOLTAGE THERMOSTAT. |
Brian (Bigbusguy)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, January 08, 2005 - 1:29 pm: | |
Ok thanks I will.
Brian 4905 |