I've read through a lot of the threads over the last two months on the Proheat, but I still have questions.
I am thinking I will have five or six zones in my system: Bedroom heat, bathroom heat, front area heat, driver heat, bay heat maybe, and domestic hot water. I plan to circulate coolant everywhere when the system is needed and just turn on the fans for the heater cores when a zone calls for heat.
Will the coolant pump in the Proheat X45 handle all this or will I need an additional pump? What type of pump would be best for this? Even if I don't need an additional pump, I will probably want one so I can circulate coolant through a heat exchanger to use engine heat. What type of pump won't restrict coolant flow if it is not turned on?
Circulation pump out of a transit donor might work well?
It has done what you intend all its life.
The pump in the proheat is no slouch, it might be fine on its own.
My Webasto is inline to the coach stock HVAC and the defroster, and its pump doesn't get in the way of massive amounts of hot water for the front end.
happy coaching!
buswarrior
Hi Brian,
Why so many zones for such a small area?
The more zones you have, sure you will create restrictions in the system that will call for more push. How ever, if you choose all thoose zones
you will need a very large manifold [1" with sweeping 90's] to help the system flo properly.
Good luck
Nick-
I figured the number of zones might be a little overboard. Most of the recommendations seem to be to use a manifold and parallel runs instead of doing everything in series. I suppose I could combine the bedroom/bath zones and the front/driver zones since I just plane to run the heater core fans as necessary and not have zone valves.
My driver's area is very hard to heat as the driver is pretty far below the passengers. The driver's heater core that is original to the bus still works, but doesn't provide a lot of heat. Running the defrosters will actually warm up the front living area pretty well on the road, but does little for the driver.
I was over to see Craig Shepard's bus the other day and his manifold has sixteen connections which I suppose means 16 zones. That does not even include the engine preheat. Craig has two 24 volt pumps, but does not have to use both. He has an Aquahot that he has customized by removing the original pump.
Quote from: buswarrior on January 01, 2008, 12:09:03 PM
Circulation pump out of a transit donor might work well?
It has done what you intend all its life.
That is exactly what I used. a 12 volt circulation pump from under the rear seat of a old Fishbowl.
I put mine between engine and the webasto, eliminated the webasto pump completely and runs to the zone control valves. This pump was designed to pump 40' in the fishbowls.
I might hook it up thru a relay on the webasto so the webasto starts and stops the circ pump. Currently I control with 2 toggle switches. ( my preference )
I think you don't need that many zones as once it starts radiating the heat they willbe all off.
You will get plenty of bay heat from the ProHeat it's self so you can eliminate that zone. The pump on the PH might not be sufficient to handle all the system at once. We are using 110 volt pumps for a house type boiler. The use of flat plate heat exchangers for domestic hot water even with a hwt is crucial. Zone valves with thermostats for each and aqua stats for you fan controls.
The Proheat itself won't be in a bay due to space limitations. It will be mounted where the original Webasto was next to the engine. I will proably leave out bay heat as it usually isn't cold enough to worry about freezing the tanks.
I assume the 110 volt pumps are because they are cheap. I would like to avoid going through the inverter if I can because I boondock most of the time. I should probably call Nimco to see what they have for coolant circulation pumps.
Why a flat plate exchanger for domestic hot water if I have a marine water heater with heat exchanger?
Finally, do the inexpensive clip-on Grundfos aquastats work fine? They say they are 115v, but I assume they are just a bimetal switch or something so they probably work at any voltage. I was only planning on using an aquastat to monitor domestic hot water, but it look like you use them for other things.
Thanks foir any info you can provide. I've got some time to plan this project as it will be too cold to work on the bus for a few months.
I think that I am going to have 40 zones in my system, what could be better than 1 per foot?
The Pro-Heat pump will be fine on it's own. No need for an additional pump. I'm using a 3/4" heat loop with monoflow Tees to feed the toe kicks. that allows very little restriction in the system. I have a zone valve to control that loop, but have a thermostat controling the fan on the toe kick in the bed room. Donn
Brian,
My pumps are March 809-BR-HS-24V. You can order them through Indelco Plastics in St. Louis Park. About $200 each in 2004.
They're a magnetic drive pump and work very well. They can be purchased in 12V or 24V. 1/2" connections.
You'll want to use 3/4" PEX everywhere except your actual runs. This is because the 3/4" barbed copper fittings are inserts, and actually provide a 1/2" opening. I would purchase premade manifolds from Menards, and connect them to the system with 3/4" PEX. The manifolds have 1/2" valves and connections for the zone runs.
craig
Quote from: gumpy on January 02, 2008, 06:22:15 AM
Brian,
My pumps are March 809-BR-HS-24V. You can order them through Indelco Plastics in St. Louis Park. About $200 each in 2004.
They're a magnetic drive pump and work very well. They can be purchased in 12V or 24V. 1/2" connections.
You'll want to use 3/4" PEX everywhere except your actual runs. This is because the 3/4" barbed copper fittings are inserts, and actually provide a 1/2" opening. I would purchase premade manifolds from Menards, and connect them to the system with 3/4" PEX. The manifolds have 1/2" valves and connections for the zone runs.
craig
I'll second the recommendation for the March Magnetic drive pumps! I like them and they have worked excellent for me. Also, I'll second the use of Menards prebuilt manifolds. Easy and quick and they work perfect.
I've got a Johnson magnetic drive booster pump in my system - bought it a few years ago from a marine supplier (in Alaska if I remember correctly) but just finally got it installed this fall. It made a huge difference. I have a parallel system & I am trying to make up for poor design on the coolant runs that left the drivers compartment starved for coolant flow. Just remember when you are laying out a parallel system that coolant will take the path of least resistance.
Brian,
I am with you; I am planning on 4 or 5 zones. While researching equipment I came across these pumps http://shop.solardirect.com/product_info.php?cPath=69_71_84_72_73&products_id=363 (http://shop.solardirect.com/product_info.php?cPath=69_71_84_72_73&products_id=363)
I finished the installation of our ProHeat system. After installing the rebuild kit in the coolant pump, the system works great. I still have the aux. pump installed in series in the loop. The OEM coolant pump is rated at 8 GPM. The aux. pump I added is 4.5 GPM. We are running only the OEM pump. With both pumps running, the flow indicator does spin faster. My concern is that if the water flows through the boiler too fast it will not absorb as much heat. ??? Jack
Is anyone using a extra pump and the engine to provide heat while cruising down the road? I would use a flat plate exchanger to get heat to/from the engine. Would I need an 8 GPM pump like the Proheat already has?
I've seen the El Sid pumps, but I don't think they have enough GPM for my needs. They are also fairly spendy compared to the March pumps others have recommended.
I called Teleflex Power to find out if the built-in pump will work, but I had to leave voicemail.
Quote from: belfert on January 03, 2008, 04:24:59 PM
Is anyone using a extra pump and the engine to provide heat while cruising down the road? I would use a flat plate exchanger to get heat to/from the engine. Would I need an 8 GPM pump like the Proheat already has?
I have a separate pump on my engine preheat line. It's only used when I'm actually heating the engine. When the engine is running, the engine pump pushes water through this pump and heats the Aquahot reservoir so I have hot domestic water when I stop for the day.
The heat exchanger will not provide enough heat for use in heating the bus while going down the road. You'll have to run the proheat unit.