|
Author |
Message |
Ray White
Joined: 02 Dec 2014 Posts: 6322 Location: Derby
|
Posted: Mon Mar 15, 2021 9:14 pm Post subject: Help needed wiring in heater. |
|
|
The four wires red, black, orange and yellow are attached at the blower end by a multi connector. The other ends are to be connected to the blower switch.
The switch has five terminals:yellow (low), red(medium) and orange (high).
The 5th terminal is for a 12v feed. Is it B or C ? and does it depend on positive or negative earth?
The relay has a white wire from 85 to (presumably?)a wire from the switch... if so which one?
The next question concerns the yellow wire from 87 on the relay. It presumably joins to the other end of the same wire that goes to the blower. If so, which one?
In other words I wish to put a relay in between the switch and the heater but I don't know which wire to cut.
I would appreciate any help.
Last edited by Ray White on Tue Mar 16, 2021 4:49 pm; edited 2 times in total |
|
Back to top |
|
|
MikeEdwards
Joined: 25 May 2011 Posts: 2474 Location: South Cheshire
|
Posted: Tue Mar 16, 2021 10:50 am Post subject: Re: Help needed wiring in heater. |
|
|
Ray White wrote: | The next question concerns the yellow wire from 87 on the relay. It presumably joins to the other end of the same wire that goes to the blower. If so, which one? |
As I see it, you'd need to have three relays, one for each speed, and wire them individually to control the L, M and H wires from the switch to the fan motor. It'll be interesting to see whether anyone more knowledgeable has a better solution, but I can't see how you could keep the speeds separate using a single relay. _________________ 1976 Vauxhall HP Firenza, 1976 Vauxhall Sportshatch (x2), 1986 Audi coupe quattro, 2000 Audi TT |
|
Back to top |
|
|
ukdave2002
Joined: 23 Nov 2007 Posts: 4106 Location: South Cheshire
|
Posted: Tue Mar 16, 2021 1:55 pm Post subject: |
|
|
You would only require a single relay for the 12v feed.
Dave |
|
Back to top |
|
|
Ray White
Joined: 02 Dec 2014 Posts: 6322 Location: Derby
|
Posted: Tue Mar 16, 2021 3:14 pm Post subject: |
|
|
ukdave2002 wrote: | You would only require a single relay for the 12v feed.
Dave |
Forgive me but I thought the wire from the relay needed to be connected to a wire that took current from the switch rather than supplied current to it. ?
If that is right then perhaps the "B" outlet should go to the relay? |
|
Back to top |
|
|
Minxy
Joined: 22 Sep 2010 Posts: 272 Location: West Northants
|
Posted: Tue Mar 16, 2021 5:23 pm Post subject: |
|
|
Is the relay part of the kit or are you adding it? Only reason I ask is that it’s unusual for a heater fan circuit to require a relay. _________________ Hillman minx convertible. Lanchester LD 10 |
|
Back to top |
|
|
Ray White
Joined: 02 Dec 2014 Posts: 6322 Location: Derby
|
Posted: Tue Mar 16, 2021 5:48 pm Post subject: |
|
|
Minxy wrote: | Is the relay part of the kit or are you adding it? Only reason I ask is that it’s unusual for a heater fan circuit to require a relay. |
I am adding relays but you are right. I am thinking it is
not required and it's too much faffing about. I need to think what I am trying to protect. The switch. It is only worth a few pounds so not worth the time and trouble. |
|
Back to top |
|
|
Bitumen Boy
Joined: 26 Jan 2012 Posts: 1735 Location: Above the snow line in old Monmouthshire
|
Posted: Thu Mar 18, 2021 2:38 am Post subject: |
|
|
Ray White wrote: | Minxy wrote: | Is the relay part of the kit or are you adding it? Only reason I ask is that it’s unusual for a heater fan circuit to require a relay. |
I am adding relays but you are right. I am thinking it is
not required and it's too much faffing about. I need to think what I am trying to protect. The switch. It is only worth a few pounds so not worth the time and trouble. |
Exactly. Relays are a good idea to protect original swichgear that is fragile, rare or both; but for modern generic switches that are readily and chaply available - and probably well able to handle more current than you'll be putting through them - they add nothing but complication and expense. |
|
Back to top |
|
|
Ray White
Joined: 02 Dec 2014 Posts: 6322 Location: Derby
|
Posted: Thu Mar 18, 2021 9:40 am Post subject: |
|
|
One thing which I am not sure about is what I need to do to about fitting the heater with my car being positive earth.
Because I don't really understand electrics I need to take advice to prevent me from making an expensive mistake. Will I need to swap over some wires or will the motor burn out run backwards?
Please help. |
|
Back to top |
|
|
MikeEdwards
Joined: 25 May 2011 Posts: 2474 Location: South Cheshire
|
Posted: Thu Mar 18, 2021 10:17 am Post subject: |
|
|
Ray White wrote: | or will the motor burn out run backwards?
|
I believe that a lot of modern motors are not polarity-conscious, so don't run backwards when voltage is applied the opposite way around to what was expected. I don't know how you would tell whether this is one, other than by applying voltage to it as an experiment.
No idea on the rest, sorry. _________________ 1976 Vauxhall HP Firenza, 1976 Vauxhall Sportshatch (x2), 1986 Audi coupe quattro, 2000 Audi TT |
|
Back to top |
|
|
Ray White
Joined: 02 Dec 2014 Posts: 6322 Location: Derby
|
Posted: Thu Mar 18, 2021 11:20 am Post subject: |
|
|
MikeEdwards wrote: | Ray White wrote: | or will the motor burn out run backwards?
|
I believe that a lot of modern motors are not polarity-conscious, so don't run backwards when voltage is applied the opposite way around to what was expected. I don't know how you would tell whether this is one, other than by applying voltage to it as an experiment.
No idea on the rest, sorry. |
Thanks Mike. Do you know if that is what they call "series wound"? Perhaps that is what I need to find out? |
|
Back to top |
|
|
MikeEdwards
Joined: 25 May 2011 Posts: 2474 Location: South Cheshire
|
Posted: Thu Mar 18, 2021 7:00 pm Post subject: |
|
|
Ray White wrote: | Thanks Mike. Do you know if that is what they call "series wound"? Perhaps that is what I need to find out? |
Sorry, I don't. That bit was pointed out to me when I posted in a discussion somewhere, the person had bought a cooling fan that fitted on the opposite side of the radiator to where they wanted to fit it, and moving it would cause it to turn the wrong way. Foolishly I posted "surely just reverse the feed wires?" and was jumped on very quickly.
Since then, and a few similar incidents, I try to phrase things in a way that (a) make them a question rather than a statement and (b) make it clear that I'm not certain, unless I am absolutely 100% certain. _________________ 1976 Vauxhall HP Firenza, 1976 Vauxhall Sportshatch (x2), 1986 Audi coupe quattro, 2000 Audi TT |
|
Back to top |
|
|
Ray White
Joined: 02 Dec 2014 Posts: 6322 Location: Derby
|
Posted: Thu Mar 18, 2021 8:07 pm Post subject: |
|
|
I also have an electric fan but the fitting instructions actually say it can be a "puller" or a "pusher" by switching polarity..
I have spoken to Car Builder Solutions about the heater and the guy said just reverse the wires for positive earth. Sounds simple enough! |
|
Back to top |
|
|
|