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fishguy
03-02-2012, 08:39 AM
Does anyone have a part # for the speed control resistor in the Smith's fan? No luck so far with our host, some other suppliers, the OVLR alternate parts list or Brit sports car sites.

Alternately has anyone come up with a work around, or do you just run the fan as 1 speed?

Moat Creek
03-03-2012, 01:51 AM
When I bought my Smiths heater (E-Bay) I did not have the resistor setup. I bought a Blue Sea 7503 Digital Dimmer and a dimmer control toggle switch from West Marine (can buy on web from multiple sources). It is about 2" x2.5" and I mounted it to the bulkhead between fan & heater box . They indicate it can also be used for motor control (small motors like the fan motor) It has about 3-4 speeds and since it is digital it does not waste energy like the resistors or need large diameter wires running to switch. Pretty easy to hookup using wiring diagram with controller. Temp range is -20C to 85C so since I live in CA this works for me. For much colder climates it may have some limitaions.

Not cheap ......mine was about $50. I took my fan motor apart and cleaned & lubed it and it works real well with speed controller. See attached picture.

Digital Dimmer (http://www.defender.com/product.jsp?path=-1|328|303333|1017107&id=1334652)
Rated for multiple fixture area lighting dimming
10 Amp, 12 / 24 Volt
Manufacturer: Blue Sea Systems
Model Number: 7503

willincalgary
03-03-2012, 06:37 AM
I use a Colehersee switch. See the section "special applications"

http://www.colehersee.com/assets/files/catalogs/1303152563-CLH-080MasterCatSectionF.pdf

TeriAnn
03-03-2012, 07:12 AM
Ron Francis Wiring sells a 2 speed car heater switch that looks a lot like the one that came on the Kodiak MK III heaters. It is the closest car heater switch to the original I have seen and it is inexpensive.

o2batsea
03-03-2012, 08:03 AM
The rheostat switch shows up on ebay uk all the time for about 15 bob. There are about 5 on there right now.
http://www.ebay.co.uk/itm/180828178700?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_830wt_1239
http://www.ebay.co.uk/itm/Triumph-TR7-Rheostat-Dimmer-Switch-/200719526948?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2ebbd0ec24#ht_500wt_1256

fishguy
03-03-2012, 08:32 AM
nocalejm is closest to what I had in mind.

On the series 3 blower the resistor is mounted inside the fan shroud so it gets cooled as the air is forced into the heater core. I'm not sure I like the idea of a hot resistor inside the plastic dash...thanks for all the leads.

SafeAirOne
03-03-2012, 10:33 AM
There's not much to the original blower resistor. You can replace it pretty easily if you know its value.

If you want, I can check the resistance value on mine when I get home. I'm sure theres a hundred places where you can pick up a suitable replacement resistor in your village. Probably cost about $2.