| Author | Message | ||
| Johnny Rating: N/A |
I recall seeing something here a LONG time ago (like, 2-3 years) about a heat exchanger for hot water. Something like: you run engine coolant through one side of it & fresh water through the other for "on the road" hot water. Can anyone help here? | ||
| Gary McFarland (Gearheadgary)
Rating: N/A |
Standard marine hot water heater. Gary | ||
| John that newguy Rating: N/A |
Just take a roll of 3/8-1/2 copper tubing and coil it around a standard hot water tank, connect the ends to your engine's cooling system, and Wahlah... hot wahwah. There's two RV hot water heater companies that sell ones that do 110, propane and has the coil for the engine coolant.. (you already have coolant running to the front of the bus for the defroster, right?) | ||
| Johnny Rating: N/A |
I have coolant in the front of the bus for the ENGINE.  It's a long-nose Ford school bus, 460 gas engine. | ||
| SkipEagle20
Rating: N/A |
here is a link you might find interesting http://www.lytron.com/standard/exchangers.asp?ref=google&kw=heat_exchanger | ||
| BrianMCI Rating: N/A |
Try typing in heat exchanger on ebay, I bought three new old stock ITT three foot long units from a guy for $85 apiece a while back. Brian | ||
| BrianMCI Rating: N/A |
There's a couple on there that are stainless steel...pretty cheap too. Brian | ||
| John that newguy Rating: N/A |
Lotta' schoolies pipe the engine coolant to the back of the bus for the rear (and mid) heaters, too. Two simple "t" taps into the system (at whatever point) and a valve to shut the link off, and you're halfway there. Even running the non-existent piping isn't a big or costly deal.. Both the front engine RVs we had, had that type of system. Both gave us more than enough hot water and heat whenever the engine was running, or had been run. In fact, we found it was a great backup system, as well. If out of propane or a fouled genset, we still could produce heat or hot water. And it would seem to me, that copper tubing (or steel pipe) would be less expensive than a commercially built heat exchanger to include in the engine compartment. You're going to have to run some pipe anyway... and the "exchanged" water won't be nearly as hot by the time you get it to where you want. Just another opinion..... | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
I did this in my first bus too, and it was great. One trick though, is to find a valve called a "tempering valve" and install it. This valve takes in both hot and cold water and automatically mixes them to give a constant (and settable maximum) temperature. These are popular in solar water heating systems to keep your hot water at a constant temperature no matter what the solar heat storage tank temperature is doing. This way you can take a shower regardless if the engine is warm or hot, and not risk getting scalded. It was a very welcome addition to my system. Just type "tempering valve" into ebay and you can find them all the time for $5 to $10... there's two there right now. Or pay $41 for a new one at a solar supplier: http://www.kingsolar.com/catalog/mfg/watts/4a818.html | ||
| Richard Jones
Rating: N/A |
In regards to heating water with a heat exchanger, is a small gpm recirculating pump required to move the water through the heat exchanger and the hot water tank? I plan on using a 20 gal electric water heater and would like to pre heat the water as we travel. Thanks in advance. Richard Jones | ||
| FAST FRED Rating: N/A |
In order to assure there was enough heat foward at the drivers heater & defroster GM used a small electric centrifugal circ pump. Since its always primed , the very low maint is not a hassle. I would suggest you do the same , although there IS circularion just from the engine , on a short run you might not get much hot water. IF you have never used one of these BEWARE , as your tap water can be 180F and almost skin you alive. Solution is an anti scald valve , or great care. With kids aboard , the antiscald would be only choice. FAST FRED | ||
| Stephen Fessenden (Sffess)
Rating: N/A |
No need for a booster pump for an engine coolant hot water heater heat exchanger. We have plenty of hot water in a half hour without an auxillary pump. My bus does use auxillary pumps for the baseboard heating. | ||
| Brian (Bigbusguy)
Rating: N/A |
Stephen, How did you plumb you base board heaters? In series or each one T ed off the line. I have 3 forced air heaters I will be putting in my 4905 and cutting into the coach heater lines. Brian 4905 Klamath Falls Oregon | ||
| R.C.Bishop
Rating: N/A |
Force 10 has a built in thermo control which cuts off the incoming coolant ( you plumb a by-pass). As I recall it is set at 150 degrees. Have used it for a year or so and am well pleased with it. Defender Industries puts them on sale from time to time. I have an 11 gallon model. FWIW RCB '64 Crown Supercoach (HWC) | ||
| FAST FRED Rating: N/A |
The F10 are great , but don't use one if the water run continues to run a box heater. FAST FRED | ||
| Stephen Fessenden (Sffess)
Rating: N/A |
The baseboard heaters are plumbed in parallel. each has its own 3/4 inch heater hose circuit from a manifold at the heat reservoir tank. The wife likes the bedroom cold and the bathroom warm, so parallel will definitely be better. | ||
| R.C.Bishop
Rating: N/A |
FF...please ex plain your last remark....??? Thanx. RCB | ||
| FAST FRED Rating: N/A |
" but don't use one if the water run continues to run a box heater." The valve in a F 10 hot water supply will slow the flow , upon reaching temperature. So any box heater will suffer from the reduced flow . as soon at the domestic hot water gets to temp. A seperate feed circuit would be better than plumbing in series , or a dumber hot water heater . FAST FRED | ||
| R.C. Bishop Rating: N/A |
Gotcha....what I thot you meant... I did!! Thanx, and Happy New Year!!! RCB |