Friday 12 October 2012

Heater planning

I'm not able (or allowed) to do any work on the car, so in the meantime spent some time looking into heater options. I still don't know if the heater will be fitted, and probably anyway post IVA - but no harm in a little window shopping and planning.

There is a lot of comment about the heater not being necessary, and/or heaters are for wimps etc... I just have this memory of bombing about in the Spitfire and my right hand getting freezing cold (even with a heater), and then later when I'd worked out how to bleed the system - at least my bottom half being warm!

My plan is two permanent heater outlets into the footwells & two outboard - just under the dash as hand warmers.

Heater Matrix/Fan

The obvious place for the heater to sit is behind the central console area on the tunnel, it even looks possible to lower a little but I really need to mockup the scuttle area to finalise this. I think a recirculating setup will be fine; i.e. no external feed of fresh air into the unit - there should be no lack of fresh air in an open car.

Still not decided on top opening as well as sides - or the pictured version which has built in bottom vents vs. pipes and separate vents - it depends how much height is available under the scuttle to get de-mist vents in place.

I'm not going to worry about diverting air to demist vents vs inside the car, it will be a basic setup where all outlets produce hot air permanently when the fan is running and hot water valve open - need to keep things simple.


Controls

One more latching button on the central console area for the fan on/off which I can get in the same style as the other switches. The hot water on/off isn't so easy to make look nice - choices between a knob or simple push/pull - I'm favouring a push pull currently - understated/simple - pull for heat.







Water Feed

I think a direct feed from the silicon hose next to the thermostat using a bolt on take off & the cold feed going back into the silicon hose at the water pump. This means I will only get a full hot water feed when the thermostat opens, and before that just the trickle/circulation flow through the thermostat hole. The advantage is I can retro fit the plumbing at any time with minimal changes.

The water pipes can route from the engine bay, along the top of the bellhousing/gearbox area to the matrix - it should be reasonably tidy, i.e. no need to make holes in the firewall/bulkhead.


Heater parts seem to be stuck between 5/8" & 1/2" standards, variously sold in mm and inches: It seems  the best option is to run everything in 5/8" (15-16mm) and adjust down to 1/2" (12-13mm) just before the matrix.


Parts

  • Heater Matrix/Fan assembly
  • Heater matrix guard
  • 2" Heater vents circular & mounting brackets
  • Heater de-mist vents & 2" adaptors
  • 2" Heater air ducting
  • 15mm water hose
  • 15mm jubilee clips
  • 15mm water valve

Car Builder Solutions

  • Heat push/pull cable
  • 2x water pipe Take offs (-or- 1 takeoff & 1 tee for bottom pipe)
  • 2x 15mm to 12mm adaptors (5/8" - 1/2")

Ebay

  • Fan switch (Savage Switch)
  • Water valve

I'm going to try and keep the heater area clear during assembly, to at least leave the option open - i.e. avoid placing the fusebox in its standard location.