Hi folks, after a short run, maybe about 15 miles / 20 minutes, the heater stops blowing air through all of the vents. There *is* heat there, I can also feel a slight air flow (but only from the air flow generated by the movement of the car I think) but although I can still just hear the fan - louder when I put it to recirculate - it isn't blowing with any force at all.
I've checked that the motor driving the vent selector is OK, and that the cam is rotating properly.
If I was to place a very uneducated guess then I'd say that there is a sudden blockage after the fan itself - but I can't see how or where it might be
The fan motor itself *is* obviously working .. but I've no usable hot air coming into the cabin - and its perishing cold outside
If I go and put the aircon on there is still no air flow.
Might the fan itself have come adrift from the motor shaft?
Sometimes, if I stop for a couple of hours, the heater starts blowing air again - but only for the same short time.
Can *anybody* please help to warm me up this winter??

 

Sounds like a bad blower fan motor or resistor

Should be an easy fix

Also ensure the coolant level is good

 

Review this thread:
http://www.matthewsvolvosite.com/for...25056&p=107358

http://volvospeed.com/vs_forum/index...ed-to-replace/

Blower Motor Info:
http://www.youtube.com/watch?v=frZl49p2quk

I also wrote a quick DIY on dahs removal in case you need it:
https://volvoforums.com/forum/volvo-v70-13/diy-1998-volvo-v70-instrument-cluster-removal-bulb-change-38386/

 

I'm pretty sure the fan is OK as it changes note when I change from external air supply to recycle,it also changes note (as normal) when I alter the fan speed selector ... it just isn't delivering air to the vents

What does the resistor do? More to the point, is it recognisable as such? What might happen should I temporarily bypass it?

I have checked the coolant levels and that is OK - except I cannot guarantee there isn't an airlock anywhere - is this likely?

I'm getting quite frustrated with this, its a shame that rising frustrtion doesn't help to increase the temperature!

Apologies for the delay in answering, I live on a canal boat on the Kennet and Avon canal (in England) and to add to my frustrations I've been iced in - in a spot with awful mobile Internet connectivity, for the past five weeks.

Appreciated your initial advice though

 

Hmmmm,

Blower Motor changes notes but no air, then the fan blade assembly (cage type) probably came of the motor shaft. Time for a new blower motor.

 

Well, that was certainly an earlier thought of mine as well, but I subsequently discounted when it occurred to me that the change in note must relate to the change in load; pulling in air from outside the cabin is almost a direct path, whilst closing the flap valve meant the air flow pattern (on the suction side of the blower) is a tad more complex so it needed to work harder.

What follows may be a total irrelevence - and may confuse matters totally .. yesterday I took the car out; unusually for the V70 it felt a little sluggish (air temp circa +1*C) so I stopped in a layby and opened the bonnet for a quick look-see. The very first thing that I noticed was that the two air conditioning refrigerent pipes entering the cabin, behind the centre console - one being fitted with what I suspect is the expansion /solenoid control valve, were iced up.

This was even though I had not touched the temperature controls since the last time I drove, a couple of days back. The fan was set at three-quarter speed, air-con was 'off', air recirculation was 'off' (actually, I now remember that I had changed this one, temporarily, to allow the cabin to warm up a tad faster - and then reset it to the normal 'external air' position), both temperature controls were set at max heat and the air-flow was directed at half face / half down .

I unplugged and then replaced the power supply to the valve and also secured an adjacent short lead (with some form of 'widget' on the end of it), that was floating loose, to the car using the metal clip on its back. Going back into the cabin I exercised all the heating controls (the engine was left idling all this time) and over the next five minutes the ice on the pipes melted.

Whether this means anything at all I have absolutely no idea at all .. other than having that sinking feeling in the pit of the stomach one gets, when the thought that the whole heating and airconditioning system (my V70 has aircon, not climate control) might be knackered, enters the mind

This may be normal (I've never had cause to look before) but, on the other hand, it may mean *something* to somebody else ...

As a final thought - is it possible that one, or more, of the control flaps that directs the positive pressure air flow (i.e. after the blower) is partially blocking the air flow somehow, irrespective of the chosen outlet(s)?

Not knowing what safety features are built into the system (like reducing the airflow if there is not sufficient heat in the system - just an example) makes diagnosing where the fault may lay very difficult - although I do have to say that I am not totally convinced that the fault is in the fan motor, or this 'resistor' which various folk are talking about. I do, however, feel that *heat* has something to do with it - in some way ...

Please don't give up on me folks, I love my V70 to bits - just not this bit of it :-) Its my third Volvo (I've had 240 and 740 auto estates in the past, as well as my lad's 340 and 440s) and the only one with a duff heater!

 

Why don't you remove the blower motor for testing?
Info in the links I posted above.

 

I was trying not to have to do this but I guess it is going to be necessary so it looks like the weekend job :-(

Thanks for the links - I did appreciate them at the time but was waiting until I got home again before looking at them again (fast broadband at home - *very* slow mobile internet connection on the boat!).

 

I have read your symtoms with great intrest as it would seem I have a similar problem I wondered how you have got on, my heater normally works fine at the start of a journey but after 20 mins or miles it also ceases to produce warmth to the cabin this can be overcome by turning the temp setting to max I have a theory that a temperature sensor is not transmitting correctly but not sure where to look for it.

Another iritating fault which may be connected when the car is locked with the key fob. the heater motor starts (not always straight away) and keeps running until the car is unlocked, ignition turned on then off which is good if your near the car and hear it but now more than often seems to flatten the battery

 

Hello wullie.lang, Is your V70 a 1997 too? I ask because I associate the running of the blower motor in an shut down car with the later models. Come,say, 2001 it's a feature which dries the evaperator. I own a 2002 and I've never been able to establish a pattern with it's operation. I just turn my A/C off and run the fan on high before I reach my destination. I then turn the fan off before I stop the engine and hope for the best. My nervous system has to mind the car's nervous system. Ha-ha. Kira

 

A couple of things to look for
1 - Remove blower motor and test it - may have gone bad - usually its the resistor in the motor - a rebuilt unit should take care of it.

2 - you may have a bad or leaking heater core.

3 - THe heater contols may be be bad - it happens to all volvos after a while check the cabin temps sensor or else ots the center panel which may need replacing.

Get someone at a good indy volvo shop to run it thru Vadis.

Best way.

cheers

 

Hello. Did you ever solve this problem? My problem is similar if not identical. Driving in cold weather, I can hear the blower and there is warm air flowing through the vents into the cabin but with no force at all. Then, when I turn off the engine the (radiator?) fan runs for awhile. Should I just try replacing the thermostat?

 

fan motor has a tendency to have the resistor go bad

try replacing the motor

things should work after that

if air is still cold

check - coolant level, thermostat and perhaps a leaking heater core

if heater core is bad u will get misting and maybe a smell in the car when windshield defrost is on....

most likely it's the motor.. good rebuilt units available and its pretty much an easy and cheap fix

eeuroparts.com has good units at good prices

 

Never managed to fix it - - the guy looking at it for me suspects it may be to do with the vent flaps as the motor turns OK and I do now get heat through the upper vents (face level) but the feet still freeze and screen demister doesn't get much air either :-(
Because I cannot bend (bad back) I'm in the hands of others now - very frustrating and very cold at the moment because what little bit of air that does slink by my feet is cold! I'm just about managing as I can wrap a 12v electric blanket around my legs (the car, by the way, is an auto so not a lot of pedal work!)
I may have to bit the bullet, get a second mortgage, and take it to a Volvo garage ...