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Coolant circulating tank heater vs EBH?

Discussion in 'Gen 3 Prius Accessories and Modifications' started by NoMoShocks, Dec 4, 2010.

  1. NoMoShocks

    NoMoShocks Electrical Engineer

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    Camas, WA
    Vehicle:
    2010 Prius
    Model:
    IV
    The topic of using a circulating tank heater instead of the EBH has been discussed very little. I was wondering if anyone knows of drawbacks to heating the coolant to 150 to 175 degrees before starting a drive. This might take about 1 hour at 1500 Watts vs. the 3 hours with the 500 W EBH to get the coolant up to 100 degrees.

    I'll need to figure out the Gen III cooling system design in order to pick good connection points to bypass the coolant mechanical thermostat.

    Products such as $40 Kat's 13150: http://www.amazon.com/Kats-13150-Aluminum-Circulating-Heater/dp/B000BQUUR6

    or the $65 ZeroStart 330-8003:
    TANK TYPE ENGINE HEATER 1500 WATT | StreetPerformance.com

    Anyone have experience to indicate the Zerostart is worth the extra $30?
     
  2. Jerry

    Jerry Junior Member

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    According to several posts in other forums, there is no pump in the Zerostart so it's the same as a block heater. Presumably there is more heat lost through the hose compared to a real block heater, which is probably why they are indicating three hours to get the engine warm (a Prius block heater takes about an hour).

    The Kats has a pump. I just wish it didn't look so cheaply made but perhaps the picture is bad.
     
  3. donalmilligan089

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    Did you find an answer to your questions? I would like to know if a tank heater is compatible to the 2006 prius. I have the block heater installed but temps only reach 95 deg. My trips are all short and would like to get temps to 175 or so be fore leaving [email protected]
     
  4. NoMoShocks

    NoMoShocks Electrical Engineer

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    No one seems to want to talk about them. I have an EBH on my 2007, and it will not raise the coolant above about 100 F.
    I think I will just have to get one of these tank heaters for my 2010 and post my results or quietly lament my woes.

    As far as the Circulating Tank Heater having or not having a pump, if plumbed correctly, it may not need one. Hotter coolant will rise, rawing colder coolant into the tank and creating it's own circulation.
     
  5. NoMoShocks

    NoMoShocks Electrical Engineer

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    Time to Bump this Topic because as I threatened to do, I have now installed the Kats 1500 Watt Circulating Tank Heater in my Gen III and had it up and running for a few weeks. It does indeed raise my coolant temperature up to 132 deg. C in less than 1 hour and then holds it there via thermostat. The 500 Watt EBH in my 2007 can only get the coolant up to about 105 deg. F. after about 3 hours.

    Lack of a pump is of no concern because the tank heater works on the theory that cold coolant is heavier and sinks to the bottom of the cooling system, so you simply need to properly orient the Tank Heater in a vertical position with the arrow pointed up, intake plumbed to a low part of the cooling system and outlet plumbed to a high point in the system in places that will bypass the cooling system thermostat.

    As the coolant is heated, colder coolant sinks forcing the heated coolant up through the outlet creating circulation until the heated coolant makes its way around the circuit back to the inlet of the tank heater and when it all gets to 132 deg. F, the thermostat begins to cycle around that temperature. I am trying to contact KATS to see if I can get one with a 160 deg. F thermostat.

    The Coolant Drain Cock on the back of all Generation Prius Blocks is the perfect Low Point and when removed, has same size threads as the hose fitting supplied with the KATS heater. For the High Point, I used the Exhust Coolant Preheat hose behind the cylindar head back by the firewall that includes the Air Bleed Valve (Highest point in the system) on Gen III. Don't know if Gen I and Gen II have Air Bleed Valves, but either heater hose entering the cylindar head should work OK with the Y fitting supplied by KATS.

    Photo 1 = My KATS tank heater (the cylindar with the RED strap around it) mounted low back on the fire wall behind the passenger side of the block.

    Photo 2 = Onboard WOODs Electric Timer that activates the Tank Heater 1 hour before each direction of my commute. This timer has 7 day 8 event programming that is mainteined with battery Backup while the car is unplugged. I have it set to heat the cooling system Mon - Fri only, becuase I use the same cord and plug for my Enginer Kit that also charges on the weekends.
     

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  6. kswebb1

    kswebb1 Junior Member

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    How do you like it so far?Would you install it again??Anything you would do different on the install??

    Im thinking of installing one in my 2011.
     
  7. PHEV-1

    PHEV-1 Junior Member

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    Location:
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    2012 Prius Plug-in
    Model:
    Plug-in Base
    Kat's Coolant circulating tank heater, Gen III

    I am planning to install the same heater. Do you have any other pictures or comments about the install that might help a DIY?

    I also have a A123 Hymotion L5 installed (for over three years), along with a battery (for Li-Ion) heater, block heater, oil pan heater and cabin heater (next, after tank heater is a cat heater).

     
  8. josh2008

    josh2008 Active Member

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    Will it only get to 130s? Is this outside or in garage? Ambient temp? Was hoping for 150s after an hour with this heater.
     
  9. bartonramos

    bartonramos Junior Member

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    Location:
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    Vehicle:
    2006 Prius
    Model:
    II
    I have an EBH installed in my Gen II.
    But I've also had that Katz heater for a while too, unopened, wondering how to really install it. Do I need to loose all my coolant to connect it to the Coolant Drain Cock? Do I attempt it myself or go to a mechanic with a lift?

    I'd also be interested to know more about PHEV-1's cabin heater.

    Lastly, I'm interested in setting up a charger+battery+inverter to power EBH when away from home and an AC power source isn't available. I have some numbers and thoughts regarding that, but wonder if anyone has actual experience doing it?