Xantia Heater blower relay mod

[Old-Guy]

The heater blower suddenly stopped working yesterday afternoon, so it looks as though I shall have to fit a relay as per the well documented wiring modification.

Although I've long known that I'd probably have to do this one day, I've now noticed that a 30A relay is suggested. As I've got a set of (ex-VSX) 25A relays, I'm trying to work out if I could sensibly use one of these instead of waiting until tomorrow and buying one from a factor or auto-electrician.

This relay will have to switch the power for the blower circuit (Fuse #20 - 20A) plus the 'small' switching current for the heated rear window relay.

A 20A fuse will carry 30A forever without blowing, but relays aren't as forgiving of abuse. So although replacing failed relay is relatively easy, it would be bound to fail at a really inconvenient time like a sub-zero night when both HRW and heater are essential!

So, please can can anyone tell me with certainty:

• 1. What maximum current does the blower circuit draw?
  2. What a typical switching current for a Xantia relay is?
  3. Which of the following Xantia S1 relays is most suitable in terms of what purpose they are intended for:
  • 03.601 [Green] 25A single contact (N.O. - no pin 4)?
    03.501 [Black] 25A changeover (pin 4 to pin 5)?
    03.517 [Purple] 25A changeover (pin 4 to pin 5)?
  4.The schematic on the last one shows something in parallel with the coil; does this hold the relay On using a lower coil current once the relay has switched?

[Clogzz]

The 03.501 relay is rated at 25A.
Don't know about the purple one.

[Old-Guy]

Thanks Cloggz, I didn't explain myself clearly enough, original post now edited.

[Peter.N.]

If its the same blower that the XM uses that regularly burns out the 30a fuseholder uner the bonnet although it doesn't blow the fuse, its obviously operating near the limit though. The safest thing you can do is connect an ammeter in series with the supply and check it.

Peter

[Old-Guy]

Thanks Peter. A bit alarming that. The 20A fuse (fuse 20) is intact, first thing I checked. So it looks as though I'll have to get a meatier relay. Somewhere I've got a small box of relays etc salvaged from the Maestros that we had for the kids when they were learners. But I suspect that none of them will be rated any higher.

Thinks, the Maestro BoL is probably easier to find - I knew it might be useful one day!

[citronut]

The 03.501 relay is rated at 25A.
Don't know about the purple one.

both of those relays state 25A