| Author | Message | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
The previous converter(s) on my Fishbowl, removed the blowers and cores from underneath the bus, probably to gain some space for the tanks. They also removed the heater lines to the pump and modulation valve, but they left those items in the back of the bus, under the bed frame. The driver’s defrost core and blower are still in place, but disconnected. What I’d like to do, if possible, is to hook up new hoses and get the driver’s defroster working again AND place new toekick or van-style heater cores and fans throughout the bus for heat when we’re driving. It seems a waste not to take advantage of the ”free” engine coolant that’s 160 – 180 deg. F. for winter/fall driving. Per Da Book, the modulation valve worked in concert with a Grad-U-Stat (some sort of proprietary thermostat, I’m sure), and functioned by air pressure to control the amount of heated coolant running through the cores. The “Stat” is long since gone with the blowers, and looked to be a maintenance item anyways, with its bellows and springs and the like. So, the modulation valve might not be able to work with a new system, and that’s fine. Assuming the pump and defrost blower still work, or if I can cheaply get replacements if not, does anyone know of a way to control the amount of heat coursing through the coach, short of off/on/ and fan speed? The whole bus is 12v, so maybe I could jerry-rig some automotive-style surplus heater controls/cores to work with the hot coolant and make it not-so-hot when the need arises. I’d also put gate valves in the back to stem the flow of coolant through the bus during cooling season. Thanks for any and all help… and any gentle criticism of my plans and ideas, if I truly deserve it. Brian Brown ’68 T8H-5305 http://www.browncowpro.com/bus/ | ||
| Tom Caffrey (Pvcces) (65.74.66.104)
Rating: N/A |
Brian, one of the reasons that they used modulation valves to control the main heater was because the size of the heater and the BTUs available from the engine could cause a serious overshoot condition in temperature control in the cabin. If you could figure out how to make the water flow variable, then overshoot might not be much of a problem. In our coach, we just turn on and off the blower and leave the hot water circulating. The heat output is quite low with the blower off. We plan on installing a line thermostat to control the fan. It is designed to handle electric heater loads, so I would think it could control a relay that turns on the fan. I'm also planning on putting a switch in series with the heater switch so I can choose between manual and thermostat control of the blower on either high or low speed. Most of the time, there is plenty of heat with the blower set on low, so it's quieter and uses less power. HTH Tom Caffrey PD4106-2576 Suncatcher | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
Thanks for the insight, Tom, and the ideas from what you've done in your coach. It's interesting that you mentioned about making the flow variable, because I was reading through Da Book again and saw that the modulating valve varies it's "modulation" via air pressure between 6-12 psi from the t-stat (which I don't have). BUT, if I can find a super-sensitive regulator to control the modulation between 6 (full on) and 12 (full-off), I could at least manually control the amount of coolant coursing through the bus. Given a long enough hose to the valve, I guess that I could control the flow from nearly anywhere. FYI, a nice guy named Ron emailed me off-board and gave me a link to a schoolie parts site that has heater parts, cores, blowers, etc. www.tacbusparts.com It might be a good place to pick up some parts for my home-brewed road heat system. Tahnks, FBB | ||
| bruce king (67.170.101.3)
Rating: N/A |
This is kinda what I've been thinking about. Basically how about taking a couple of pumps (sureflo, for instance) and using a thermostat to control the pump. and then do this. put marble tiles on the floor of your bath and kitchen. Underneath the marble, put 1/2" thinset, and in that cement put a 3/8 copper pipe -- maybe 50' of it, in narrow zig-zags. Hook the pump up so that it forces hot water through the thing, and voila! radiant floor heating, and silent. Plus nice to have a warm bathroom floor. | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
I found a regulator from McMaster Carr that just might fit the bill to run the modulator. 0-15 psi range, with 1% accuracy, and for panel-mount applications. The nice, tight range might make a good temp. selector for me. Model #41795K3 for $32. http://www.mcmaster.com/ Site uses frames, so no direct-link for anyone else curious. 1/16" pipe size seems so TINY though. I'd still need some heater cores and blowers. FBB | ||
| FAST FRED (4.245.230.211) Rating: N/A |
Most likely the amount of heat avilable from new installed heaters will be far less than what was fed to the old air cond output.(bout 180,000btu) The cable operated valve (normally used to vary temp for drivers heat) is only $12. or so and can be installed to controll other heaters. Our system was to retain the drivers heater/defroster and cut in a second 40,000btu marine unit that is fed outside air via the old outside supply for the AC. I get to adjust My heat , and the bride has infinate controll and 3 speeds to play with. Mostly its just on or off. This keeps the rear of the coach cooler than foward , but if its 70 foward , its probably 50 aft in below freezing weather. Not much for the furnace to :catch up: after parking. Aft a second heater core could simply be thermostated to run the blowers if uniform rear temp was needed going down the road. KISS,,Works for me, FAST FRED | ||
| Simple n easy (199.64.0.252) Rating: N/A |
How about a ball valve mounted in the dash with the handle sticking out. Run your supply line through it. Then all you need to do is adjust the ball valve to regulate the amount of coolant running through the core. Simple. $5 for a valve. A few more for some fittings and clamps. Use the engine pump as designed. | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
FF: Thanks for the ideas. So, the driver's defrost must mix in outside air to "modulate" the temps. This would also help with fresh air intake, which might be healthy for us... unless we're following an old bus like mine *LOL*. I'll look around for a similar 40k BTU unit like you mentioned. The bus has two fresh air intakes, one on each side amidships that served the old blower motors underneath that I might be able to get to duct into a new air-type unit like you mentioned. Thanks! FBB | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
Simple: Hey, your ball-valve idea is a LOT more KISS than me trying to modulate a 35 year-old device with a finite amount of air pressure... with no idea whether said modulation is modulating. Okay, enough with *that* word, FBB. I like it! So... maybe I could create a system of pipes/valves, like branches of a tree (or a hydronic system), serving each of the areas of the bus I want, with a fan control and ball valve at each core, then branched right back into one big return line. Surely the old heater coolant pump could keep up, since it sounds like it was designed to move a LOT more coolant and heat than I'll need. OR, maybe I wouldn't even need it at all and let convection and the engine pump move the coolant through the bus. Now, if someone would just give me a $3000 Webasto heater (Santa, I've been a good boy this year)... I'd be set for park mode, too. You've really got me thinking now. Thanks! FBB | ||
| DrivingMissLazy (66.168.175.51) Rating: N/A |
Be very careful with the fresh air intakes. I had one on my Eagle that I was never able to locate and it brought in a large amount of HOT air in the summer. I had to tape off the grills on the toe kick heaters to stop the flow of hot air. Make sure you can shut them off completely for summertime. Richard | ||
| FAST FRED (4.245.230.86) Rating: N/A |
The drivers heat controll is a fine valve that hooks up to a choke cable to be remotly operated. Works great doing what it was designed for for $13.or so. ON my GM the drivers defrost hook to the heater fan , and to the circ water oump. Its fairly EZ to set it up so the blower comes on and the circ pump does not. This way the defroster can be used for summer cooling with out wearing out the expensive and Necessary circ pump. The old now unused rotary switch for coach heat & AC is the place to power the heater,under dash blower and circ pump. Get warm , keep cool, Works for me, FAST FRED | ||
| Marc Bourget (209.142.38.81) Rating: N/A |
Guys, depending on the number of "heat" zones you want to control in the coach, plumb your cores parallel and use the 24V Flow Control Valves from a Home Hydronics heating system. The valves will be controlled by a 24 V thermostats for each zone you wish to control. If you have the need for a circulating pump (advisable) the pump is actuated by a relay and you'llutilize the aux terminals of the thermostat to control the hydronic valves. this is to "fire off" the pumps before the control valves. There is a specific and detailed procedure for purging the system once you hook it to the engine take-offs. Get back to me on that point if you choose this approach. Onward and Upward Marc Bourget | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
DML: Thanks for the heads-up. I went out to Da Bus today and noticed that the side intakes are covered over with plywood. If I use air-based modulation with defroster cores (like FF's), I'll devise a way to shut them off in summer. FF: Thanks for more ideas and pointers. Right now, none of the switches work on the heater/ defrost system, so I'll probably end up making a dash panel for them. That'll give me the flexibilty to wire them as you describe. MB: I like the thermostats/zones idea, as long as they're not too pricey and I can find them in 12V (coach and house systems are 12V on my Fishie). And I do have a circ. pump back there, I just need to make sure it's working and/or find a suitable replacement. With any of these systems/ ideas, a separate circ. pump to help push the coolant sounds like a good idea. Thanks all! FBB | ||
| FAST FRED (4.245.128.21) Rating: N/A |
NO NO ! NO Summer cover! The blower can be used as to bring outside air into the coach anytime its nice out! For some reason mosquitos dont seem to get sucked thru the origonal vent holes , and the Canadian or Maine, Black Flies are far too big! Summer ventilation with the existing setup is still KISS, just better living thru THINKING. FAST FRED | ||
| FishbowlBrian (Fishbowlbrian) (67.165.212.171)
Rating: N/A |
Let me get this straight, FF, are you saying to leave the covers off in summer? *grin* Just kidding. Yeah, I can see the benefit of that, as long as there's positive closure through the defrost units (sounds like there would be). BUT, when I went out to the bus yesterday, I discovered that my problem now is it appears that the side covers were blocked off rather permanently with plywood before the interior walls were put up.  Sooo, I either dig into the walls to fix 'em OR set new intake vents and screens through the skin wherever I want my cores... maybe under cabinets or couch/beds. I guess this is the price I pay for inheriting someone else's conversion. FBB |