Thread: Replacement Air Conditioner Condenser Fan

May have gotten the specs wrong on the stock fan, appears the internal blower is 250W and there is no spec on the Condenser Fan when looking at Connector Three on the pdf, so the specs and hence conclusions on the stock AC condenser fan are totally wrong.

The performance of the stock fan I would surmise would therefore be lesser than I calculated as I doubt the motor is going to be 250W which I noted was at the extremes for this size fan.

It does give an easy to get at Vehicle speed signal for the Alpine Sat Nav though on Connector two pin 2, did not bother to do this before.

Hi, all i can tell you is that the genuine condenser fan's motor is made by VDO p/n PM9128, direct interchange is TYC 630870, unfortunately i couldnt find specs but maybe LR had some good reason to put a 40A fuse for it, based on some oppinions which i read on other forums seems that the fan has above 2000 CFM

Originally Posted by sierrafery

Hi, all i can tell you is that the genuine condenser fan's motor is made by VDO p/n PM9128, direct interchange is TYC 630870, unfortunately i couldnt find specs but maybe LR had some good reason to put a 40A fuse for it, based on some oppinions which i read on other forums seems that the fan has above 2000 CFM

Thanks for this. Having researched fans for the last week or so extensively as I noted, this would put at the top end of all fans such as these two

H.O. Extreme : 12" High Output Single RAD Pusher/Puller Fan with Standard Mount Kit - 13-1/8"W x 13-1/8"H x 3-1/2"D

or SPAL

• SPAL TYPE:VA01-AP70/LL-36S
• 12v
• Pushing (blowing) ideal for restricted spaces
• Depth: 96mm
• 1687 CFM
• 21A current draw
• Paddle blades to give maximum airflow
• Long Life Motor fitted for additional durability
• Standard Connector with wire harness is included

Have also seen on some forums people quoting figures as CFM but are talking M3 which has a conversion ratio of 1 m3/h = 0.59 cfm

If the figure was correct, then


Suppose to take the waffle out of it, what I am looking for is to increase the 'normal' airflow through the radiator core and reducing any impediment to this at the front in normal driving, maximizing the flow rate across the radiator before the need for fan assistance. If the OEM does flow 2000cfm and this is the requirement for the cooling system then I am only going to improve this marginally with the other fans on offer with them being slightly more open in design.

Have you considered using a manometer or magnahelic to look at the pressure differential across the radiator core? Given the restriction is fixed, flow should be pretty easily measured on a proportion basis by looking at the static pressure in front of the radiator vs on the engine side.

Easy enough to knock one up with some vinyl tube and water, but a magnahelic would be more sensitive.

Analysis is always easier with data.

Originally Posted by BradC

Have you considered using a manometer or magnahelic to look at the pressure differential across the radiator core? Given the restriction is fixed, flow should be pretty easily measured on a proportion basis by looking at the static pressure in front of the radiator vs on the engine side.

Easy enough to knock one up with some vinyl tube and water, but a magnahelic would be more sensitive.

Analysis is always easier with data.

Had looked to get anemometer last year, not so much the pressure but the cfm calculation the better ones have, just enter the fan area and the thing calculates out the CFM based on wind speed.

I thought would have been useful, but couldn't find a good place / space to measure the standard VF and then to do an accurate analysis of the actual CFM of the VF. Behind the VF is pretty much the belt and pulleys and it needs to be able to flow the anemometer reasonably unobstructed. This would be probably difficult to do this parked and really needs to be done whilst in motion and revving at speed to get it to lock.

It is not a problem with EF as there is now space to mount it but without the baseline of the VF, gives me a number only.

I read that the Derale High-Output Single RAD (2000 CFM) Fan draws 24.8 amps. Is the standard wiring in the Discovery 2 AC Condenser Fan circuit capable of handling that? Does anyone know please? Or would you need to introduce a relay into the circuit to avoid a fire?

I had a quick look for stats on the VDO p/n PM9128 and TYC 630870 suggested by Sierrafery but couldn't immediately find any figures on what their current draw might be.

Normal draw of the Derale fan is around 18A it takes 23.5 at start up Single Powerpacks : High Output Single 17'' Electric RAD Fan/Aluminum Shroud Kit - 21''W x 16 3/4''H x 3''D the vehicle's circuit which already has the relay and 40A fuse is good enough