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heater bypass valve
itsawindupuk - 21/5/13 at 08:48 PM

Hi guys, I feel my duratec mgb needs a heater and I want to use a valve like this one, but does anyone know why it has 4 ends to it rather than 2? And if so what goes where?

http://www.caterhamparts.co.uk/product.php?id_product=333


adithorp - 21/5/13 at 08:53 PM

The clue is in the name.

Feed and return to the engine and feed and return to the heater. When closed it "bypasses" the heater and just feeds back to the engine. When open ti feeds hot water through the heater and back through the valve to the engine.


ken555 - 21/5/13 at 09:12 PM

Cheaper to look for one as a London Taxi TX2 Heater Control Valve

Or use an electrical one off a Ford Ka/Puma from a scrap yard.


PeteS2k - 21/5/13 at 09:42 PM

quote:
Originally posted by ken555
Cheaper to look for one as a London Taxi TX2 Heater Control Valve

Or use an electrical one off a Ford Ka/Puma from a scrap yard.


Watch-point if using a Ford electrical one (I've got a Fiesta one on my car, which I think is pretty much a common Ford part) - it works by pulsing a 12V signal to provide the variable temp setting. I just use it as an on/off though - 12V is off, 0V is on (if I've got that the right way round!)

[Edited on 21/5/13 by PeteS2k]


britishtrident - 22/5/13 at 07:09 AM

You can use a simple 2 connection valve as long as you provide an alternative path for the by-pass flow.

To give an alternative path for the by-pass yYou can use 2 Tee pieces linked together i.e.. one in the heater flow and one in the heater return joined by a hose between the centre leg of the Tee.


VW and Audi used a simple 2 connection valve -- very cheap on eBay
AUDI 80/90/COUPE/QUATTRO HEATER VALVE 171819809E NEW | eBay


The plastic Tees sold for the coolant water connection on LPG conversions are ideal as they are cheap and are stepped to accomodate differe bores of heater hose.


Not Anumber - 22/5/13 at 09:03 AM

Are the VW valves electrical or mechanical /

If these valves are electrical at £ 7.50 a go it would be worth using 2 of them switched through a relay so water would flow only through the heater or through the bypass.


britishtrident - 22/5/13 at 11:19 AM

quote:
Originally posted by Not Anumber
Are the VW valves electrical or mechanical /

If these valves are electrical at £ 7.50 a go it would be worth using 2 of them switched through a relay so water would flow only through the heater or through the bypass.



Simple mechanical cable. for a better view see HEATER VALVE NEW FOR VW CADDY SCIROCCO GOLF MK1 CABRIOLET TRANSPORTER T25 LT 80 | eBay

You really don't need to make it over complex anyway the 2 Tee method works fine.