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Topic: Dash heater booster pump (Read 729 times) previous topic - next topic

Dash heater booster pump

With colder weather coming, I'm reminded of the slow lag time between temperature adjustments and actually feeling the change.  I have been considering installing a booster pump in the line from the engine to the dash heater.  Has anyone done this or know of a pump that would work well for this??  Thank you and have a great day.  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Dash heater booster pump

Reply #2 –
You might consider this: http://www.suremarineservice.com/906-089KIT.aspx?gclid=CL3GvoGgx7kCFexDMgody0oAuA. I found it while searching for a pump for the heater system.

I was thinking about seeing if the functionality of the motor aid water heater system could be reversed so that the propane water heater might keep the Cummins engine warm for easier starts in the winter. I figured that a 12VDC coolant pump might send heat from the water heater to the engine coolant.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Dash heater booster pump

Reply #4 –
John  ----    On that U300, where did they mount it and how is it controlled?  Is it forward in the dash, or in the rear engine comp't?  Good to know that there was one installed on some coaches. 

JD  ----  Do you have a block heater and you would want to supplement that or in lieu of??  Might be alot of heat loss in that long loop and not very efficient.  It would be interesting to see how well it worked, so if you do that, keep us all posted. 

Thanks guys and have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Dash heater booster pump

Reply #5 –
Country Coach used to use 12 volt booster pumps for the coolant to the front heater. Some were mounted back by the engine and some were mounted up front under the floor behind the front cap, so guess they could be wherever would be convenient to mount them.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Dash heater booster pump

Reply #6 –
Quote from: fkjohns6083 –
JD  ----  Do you have a block heater and you would want to supplement that or in lieu of??  Might be alot of heat loss in that long loop and not very efficient.  It would be interesting to see how well it worked, so if you do that, keep us all posted.
We do have a block heater. In temperatures below about 25F, we turn it on at bedtime if we plan to start the engine in the morning. It takes a long time to warm that big engine with a 4700+- BTU/hr electric heater. If dry camping (which we seldom do), I thought the motor aid loop might provide enough heat from the propane fired water heater to crank the engine without having to run the block heater and generator all night. The propane unit provides around 10,000 BTU/hr. Indeed, losses might be so great that the engine would get little heat. It would be an interesting experiment.

The conversation I saw on the Sprinter forum appeared to be a discussion about installing in the Sprinter a system like the three-way Atwood unit that was stock on our U295. I didn't see any discussion about sending heat to the engine from a propane fired unit. Perhaps I missed something.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Dash heater booster pump

Reply #7 –
Guess I'll know the answer better when I get a pump and know if it has a Net Positive Suction Head that will allow it to pull hot water from a longer distance.  Seems like it would be OK to mount it up front since the NPSH  from the existing water pump should be  sufficient to provide  ample inlet pressure.  Guess we'll get one and mount it where best suited.  Thanks and have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Dash heater booster pump

Reply #8 –
Quote from: fkjohns6083 –
John  ----    On that U300, where did they mount it and how is it controlled?  Is it forward in the dash, or in the rear engine comp't?  Good to know that there was one installed on some coaches. 
It's mounted in the rear next to the engine.  I think Red Tractor is correct in that it could be any where in the hose circuit.  I think there are two advantages to placing it in the back: 1. Closer to alternator and batteries.  The dash area already seems to have a lot of amperage load on it.  Pumps are a pretty good load and will draw down you dash voltage.  2. If your coach water heater has the Motor Aid feature, the pump will improve water heating - especially with the dash heat turned off.
The control switch is mounted on the dash with the label "AUX PUMP".  I'm guessing the switch is controlling a relay but I would need to check.  I can post photos of the pump if you like.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Dash heater booster pump

Reply #9 –
Quote from: J. D. Stevens –
You might consider this: http://www.suremarineservice.com/906-089KIT.aspx?gclid=CL3GvoGgx7kCFexDMgody0oAuA. I found it while searching for a pump for the heater system.

I was thinking about seeing if the functionality of the motor aid water heater system could be reversed so that the propane water heater might keep the Cummins engine warm for easier starts in the winter. I figured that a 12VDC coolant pump might send heat from the water heater to the engine coolant.
I actually tried it once in freezing conditions.  I couldn't detect any change on my digital engine temperature gauge.  I don't think much of that 10,000 BTU/hr gets out and what does gets lost on the way to the engine in freezing conditions.  I was thinking for dry camping in cold weather that having multiple engine block heaters running simultaneously on the generator could do the trick in proportionally less time.  My block seems to have an abundance of 3/4 NPT plugs on it and I can't help but think some would accommodate a heating element.  Plenty of unused watts on the generator too.  Would work too when you have hook ups and forget to turn the block heater on before going to bed.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Dash heater booster pump

Reply #10 –
Quote from: red tractor –
Country Coach used to use 12 volt booster pumps for the coolant to the front heater. Some were mounted back by the engine and some were mounted up front under the floor behind the front cap, so guess they could be wherever would be convenient to mount them.

They also had an insulated copper pipe in a track  to make sure hot water ended up at the dash.

Bob

"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Dash heater booster pump

Reply #11 –
Would not expect a Cummins engine to require a pump to the front heater as Cummins have more water pressure than most engines., my ISM does not need a pump.

Re: Dash heater booster pump

Reply #12 –
I have the heating feature for the hot water tank but I keep the valve from the heater line to the tank closed and send all of the water forward to the dash heater.  Seems like I need the dash heater more that the hot water heater and I have an electric heater if needed.  Thanks guys and have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Dash heater booster pump

Reply #13 –
Quote from: JohnFitz –
I actually tried it once in freezing conditions.  I couldn't detect any change on my digital engine temperature gauge.  I don't think much of that 10,000 BTU/hr gets out and what does gets lost on the way to the engine in freezing conditions.
Ah! I was hoping to get a reply from someone who had tried heating the engine with the water heater. Thank you for the reply. I will leave it alone.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Dash heater booster pump

Reply #14 –
My Foretravel was fitted with a rear Primus heating system as used by the Bluebird coaches.
It includes heat exchangers in the dash for heating that zone.
This is the pump that is used for the entire system. Its mounted behind 2  propane fired boilers near the engine.

http://www.dupreeproducts.com/SearchResults.asp?Cat=24
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.