| Author | Message | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1589 Registered: 7-2006 Posted From: 97.212.104.251  Rating: N/A |
Who of you uses an expansion/buffer tank?...looking for comments about "how important" you find them to be. Also, your positioning of the tank(s) and the efficiency you have experienced. Thanx  RCB | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 700 Registered: 2-2001 Posted From: 184.0.13.120  Rating: N/A |
If your Webasto system is always connected directly to the engine (not valved off) you won't need the expansion tank as the engine's tank is more than adequate. If you are heating the engine through a heat exchanger or not heating it with Webasto at all then you will need one. | ||
| Tony LEE (T_lee)
Registered Member Username: T_lee Post Number: 86 Registered: 11-2007 Posted From: 64.134.236.253 Rating: N/A |
A lot depends on how much coolant you have circulating in your system. If it is a simple circuit with the webasto, a bit of piping and the fan heater, then the thermal mass is too small and the webasto might end up short-cycling. Then you need the buffer tank to increase the volume of coolant. Still going to need a way of accommodating the small amount of expansion though. | ||
| Dal Farnworth (Dallas)
Registered Member Username: Dallas Post Number: 721 Registered: 7-2004 Posted From: 75.91.206.80  Rating: |
Don't use it, or the main tank... buy another one. | ||
| david anderson (Davidanderson)
Registered Member Username: Davidanderson Post Number: 279 Registered: 2-2004 Posted From: 69.153.56.18 Rating: N/A |
Dick Wright at Wrico sells a bunch of these. You might give him a call. I have one on mine, and placed it high in the engine compartment which put it about 3" above static level of the heater lines. I always try to park ass end high or level if I know I'm going to fire it up. Air locks are not good. Don't ask me how I know. I would think the expansion tank would be a big factor to eliminate short cycling of the furnace. That water stores heat and keeps you warm even when the furnace cycles off. David | ||
| don goldsmith (Bottomacher)
Registered Member Username: Bottomacher Post Number: 288 Registered: 12-2000 Posted From: 75.204.190.63 Rating: |
Why does the tank have to be above the static level of the heater coils? If there are bleeders at the coils, the tank would seem to work anywhere, such as expansion tanks on residential and at least some commercial boilers (water heaters). | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1590 Registered: 7-2006 Posted From: 97.213.36.214 Rating: N/A |
"Don't use it, or the main tank... buy another one." Huh???? don't use what?????...or the main tank????? Sorry, don't understand.  Jim Wilke...I think you have hit it on the head...thanx But thanx for the response....all!!! RCB (Message edited by chuckllb on September 26, 2011) | ||
| Dal Farnworth (Dallas)
Registered Member Username: Dallas Post Number: 725 Registered: 7-2004 Posted From: 75.91.206.80 Rating: N/A |
Sorry about that, I was typing, got called away and the cat messed up the post. | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1591 Registered: 7-2006 Posted From: 97.213.32.100 Rating: N/A |
Don...I agree with you...theoretically...however, I also have experience that tells me that doesn't always work. I have bleeders on all heat exchangers, and on on the hot water tank wrap, which is the high point of my system, but it occurs to me that the hour and a half or so that I spend in that process might be better used elsewhere---especially when the over heat fuse blows any way. I imagine the 100 feet or so of line plus the very large cavity in the engine (laid on it's side amidships..almost no way to fill completely) is the big culprit. 20 plus gallons of coolant! I ordered a reset fuse from Sure Marine...they were very helpful (fellow named Todd)...and I hope this will solve my problem. I just cannot see adding the expense of a $200, 5 gallon expansion tank, plus finding the right place to put the equipment, hose and connections. Doubt it would be "that" beneficial. Thanx for all the comments... and those who sent PM. RCB | ||
| don goldsmith (Bottomacher)
Registered Member Username: Bottomacher Post Number: 289 Registered: 12-2000 Posted From: 75.225.152.78 Rating: N/A |
My webasto will have a heat exchanger for the engine loop; I don't want to lose a million dollars worth of antifreeze if my heater hoses leak somewhere, or to risk the loss of the engine coolant and get stuck somewhere. As a result, my heater loop is going to be pretty small, not much over 5 or 6 gallons I think. So I installed a two gallon or so bladder tank in the system, close to the hot output line. I am still building my heaters, so I don't have the bleeders in yet, but they will be easily accessible on all appliances except the water heater, which is mounted quite low. I don't know if it will work, but I hope to find out next month. I've thought about this for months, and I don't see why the low mounted expansion tank wouldn't work. I would love to know if it won't before having to take the whole thing apart. Anyone have any experience? | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1592 Registered: 7-2006 Posted From: 97.227.24.197 Rating: N/A |
All recommendations I have seen...and heard...and experienced, are at upper most point; heat rises which pushes all air in the system to the highest level. Pretty much basic science. It would also let your exchangers be filled, once bled. the opposite in a lowered setup. Webasto states to place the unit in the lowest for that reason. Jim has a comment on that above. Not sure what you mean by losing "a million dollars worth of antifreeze if my heater hoses leak somewhere, or to risk the loss of the engine coolant and get stuck somewhere." My understanding is that closing off the heat exchanger loop is to avoid having hot coolant going thru them in warmer temps. In my case, I have a shut off valve for that purpose, but due to age, it is "frozen" and I do not want to replace a bunch of pipe. Gets really hot in the coach in the summer, tho. 5-- 6 gallons seems awfully small for a coach engine, but then I do not know your circumstances; mine is about 20 gallons, of course for the entire system. David...curious about your remark about high rear end parking???? FWIW RCB | ||
| david anderson (Davidanderson)
Registered Member Username: Davidanderson Post Number: 280 Registered: 2-2004 Posted From: 69.153.56.18 Rating: N/A |
Don, The tank should be at the highest point, the pump at the lowest so the system will burp out any bubbles as the coolant heats. The installation instructions are pretty clear about that. RCB: My tank is only about 3" above static level and in the engine room. If the bus is level or rear end a bit high I'm assured that the tank is above static level. David | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1639 Registered: 7-2006 Posted From: 97.212.175.210 Rating: N/A |
Reviving this thread.....does anyone know if there is a "less pricey" tank than what Sure Marine offers (roughly $185 for 2.5 gallon)that would be suitable for this type installation? Thanx! RCB | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 2178 Registered: 12-2000 Posted From: 174.91.144.232  Rating: N/A |
Have you tried any old heating supply? You just need a boiler expansion tank of any sort, of proportions that will fit in the space you have for it. The word "marine" is good for a healthy percentage increase all by itself... happy coaching! buswarrior | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1640 Registered: 7-2006 Posted From: 97.226.193.171 Rating: N/A |
perhaps I should have elaborated a bit... I note the tank shown on the Sure Marine site has not only two inlet/outlet connections, but also has a "radiator" type cap. No mention, that I saw, of a bladder. This would indicate a pretty low pressure situation, but the tank appears hefty,as it were. In our house floor heating setup we do have an expansion tank....but it does have a bladder and only one connection with a schrader type valve at the bottom. Big buck difference in what I am seeing,,,,plus, don't need to "waste" time, $$ and frustration on doing the wrong thing.... | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1641 Registered: 7-2006 Posted From: 70.218.176.56 Rating: N/A |
Any ideas, anybody???...how 'bout you "plumbers"? Thanx! RCB |
