940 SE, non-ac, how hot should the heater be?

[Laird Scooby]

Originally Posted by TonyS9

Have to admit my 940 heater isn't the best compared with the 360. Seems to have a poor output for longer that I think it should have.

I generally put the fan up to position 2 after the gauge starts to move, which seems to help.

Once its going about 10mins and a decent rpms it seems good.

I did put a new control valve in many years ago. It wasn't closing due to the hose being over tighened and distorting the housing, so I suspect it might have had a new matrix or something before.

Try swapping the hoses to the matrix as described Tony. You might be pleasantly surprised - and warmer!

Originally Posted by kiloran

Update:

Given the hose clamps for the matrix a liberal spraying of release oil as they're pretty corroded.

Removed the kick panel under the steering wheel (yay, torx screws into proper brass ferrules rather than use once, break once plastic clips) and can confirm the following:

1. Heater position switch is connected - arm moves when moving selector

2. Heater control valve connected - can see the cable pulling the arm when moving the heat level selector.

Some evidence of leakage from heater control valve (HCV) - see photos. But it's dry at the moment so might be from long ago.



Got heated seats for the journey tomorrow so not too bothered. And being an almost 50yo Volvo driver, time for driving gloves perhaps!

What's involved in replacing the HCV for a non a/c car? Looks like there's reasonable access?

I've got news for you - the heated seats don't work most of the time! Over 10C they're designed not to work at all, they also have built-in thermostats which switch them off (and fail) long before you're anywhere near warm enough and even then, they take longer to warm up than other cars i've had with bum warmers.

As for your HCV, if it's working, don't touch it! Not even in jest! There is a conversion using a Mk1 Golf heater valve but other than that, RHD non-air con HCVs are extinct, you have more chance of resurrecting a do-do than finding a RHD HCV for manual heating in captivity!

Good idea dousing the Jubilee clips with penetrating oil, might pay to have a couple of spares on hand in case, even if you don't try swapping the hoses yet although as i've said, that would be my first thing to try, especially as it seems they may have been off before.

[kiloran]

Originally Posted by griston64

The worst thing in replacing the heater control valve is getting one !

Just discovered that. Bother.
Still, spring is on the way, right? And it might not be leaking...

[kiloran]

Moving off topic slightly but my heated seats are epic compared to the following:

Mk4 Golf - 5 settings, all tepid
V70 - never worked
Passat - as per the Golf
Mondeo Mk3 - only one setting, more tepid than the Golf

The only heated seat I've placed my bum on that's better is the one in the 340GLE I learnt to drive in. Now that was toasty...

[kelvinp]

Originally Posted by kiloran

New owner of a '93 940SE 2l petrol non-turbo, it's the non-a/c model. Heater pushes out warm air but it's not exactly toasty - how hot should it be?

I've checked around for some of the obvious things as follows:

1. Car warms up in about 5 minutes, temp gauge sits just slightly to the left of vertical

2. Coolant level is fine (not using any coolant)

3. Rad hoses are at the temperature I'd expect I think - after a long run I can hold them fairly tightly indefinitely - should they be hotter?

4. Matrix hoses are warm as they enter the firewall

5. No evidence of any moisture in driver's footwell

6. Blower fan operates on all speeds.

7. Warm air vents respond to the rotary dial selector as expected

8. There is warm air coming from the vents, it just isn't by any means hot. A pleasant heat - I could hold my hand over the vent on maximum heat indefinitely I think.

Is this just how 940 heaters are or is there a problem? I'd always imagined something designed for the arctic wastes would have an insanely hot heater?

I don't know if 940s are the same but my 740 heater comes in warm, hot and inferno settings so it does sound as though yours is not getting as warm as it should be. After a long run I wouldn't expect to be able to hold the radiator hoses (or top hose at least) for any length of time, given that running temperature is around 90 deg C with a 92 deg C thermostat.

Always handy if you have a digital thermometer or probe for multi-meter, you can use this for checking air/water temperature.

I would go for the thermostat first - it's usually easy enough to whip out and dunk in a saucepan of water and check it opens/closes properly (and check with a thermometer).

[bob12]

Originally Posted by kelvinp

I don't know if 940s are the same but my 740 heater comes in warm, hot and inferno settings so it does sound as though yours is not getting as warm as it should be. ..................

True .... although it is all variable. Can't think the last time I used the 745 on max. heat level.

As to the heated seats in 30 years down South I have never used them except by accident until you find your bum warming and then realise what's happened! Probably don't even work now. I shall have to test them.

Bob

[Laird Scooby]

Originally Posted by kelvinp

I don't know if 940s are the same but my 740 heater comes in warm, hot and inferno settings so it does sound as though yours is not getting as warm as it should be. After a long run I wouldn't expect to be able to hold the radiator hoses (or top hose at least) for any length of time, given that running temperature is around 90 deg C with a 92 deg C thermostat.

Always handy if you have a digital thermometer or probe for multi-meter, you can use this for checking air/water temperature.

I would go for the thermostat first - it's usually easy enough to whip out and dunk in a saucepan of water and check it opens/closes properly (and check with a thermometer).

For the cost of the 'stat including a new seal, i'd just fit the new one.

The 940 should be the same as the 740, all the 740s and this 760 have operated on "inferno" when needed, if i want "thermo-nuclear blast", i use my other beast.

Speaking of which, when i wired the heated seats up on the prototype connections in it, i found the setas were very warm (much better than any of the Volvos i've had and/or experienced) and the same goes for its "sister car" that i owned concurrently for a while although that one being slightly newer had the bum warmers as standard.

Reminds me, i must get the wiring sorted properly on the other car and try and find out why the bum warmers just don't work in my 760!

[kiloran]

I've got a new stat on the way.

Just driven in traffic for half an hour or so, top hose still hand-holdable. 6 degrees outside, with heating on three quarters it was barely warm in the car set to 3/4 with the fan blowing on 1.

Further diagnostics to follow after long run tomorrow (2 hours of motorway and A-roads in rush hour). I'll look up the process for temp measurement with a multimeter...

As to my seats they're at blast furnace level

[Laird Scooby]

Originally Posted by kiloran

I've got a new stat on the way.

Just driven in traffic for half an hour or so, top hose still hand-holdable. 6 degrees outside, with heating on three quarters it was barely warm in the car set to 3/4 with the fan blowing on 1.

Further diagnostics to follow after long run tomorrow (2 hours of motorway and A-roads in rush hour). I'll look up the process for temp measurement with a multimeter...

As to my seats they're at blast furnace level

Where was the temp gauge sitting after that half hour run?

You could find a cardboard box and unfold it then use it to blank the radiator to get it to warm up more but it definitely sounds as if it's overcooling!

If you have a multimeter with a temperature range on it, it almost certainly came with a leaf-type thermocouple that will plug into a special scoket on the meter casing.
Select the temperature range then put the leaf on the hose, holding it with some insulated object (piece of wood for example) until the temperature stabilises.

[kiloran]

Originally Posted by Laird Scooby

Where was the temp gauge sitting after that half hour run?

If slap bang in the middle vertical is 12 o'clock I'd say it was 11:30, so not far off. Big chunk of the journey was in traffic, it didn't shift any higher than that. When I turned the heat full on with the blower it might possibly have shifted a little to the left, but might just be seeing things. After the long run tomorrow morning I'll double-check the carpet and HCV.

other than this issue it's running absolutely fine - previous owner delivered it from Devon in person which is a good 3 hours drive from me.

[kelvinp]

Temperature gauge at 11:30 and dropping when you put the heater on full, then I would go with thermostat failing. It's either stuck partially open or opening too early.

The symptoms with mine were the same, there was a noticeable drop in the temperature gauge needle when I was doing fast driving. Around town I didn't really notice there was a problem as it was only short runs.