Heater and dash

[Atlas]

Anybody help with knowledge of removing heater, I'm not able to bleed the heater so I need to check deeper.

 

[Cyprus Andy]

have you tried flushing it out with a hose on the bottom feed to the heater and opening the return to make sure its not blocked first ?

 

[Atlas]

Thanks Andy, I'll give it a try, I have started to take the matrix out and seem to be taking the whole dash out. Atlas

have you tried flushing it out with a hose on the bottom feed to the heater and opening the return to make sure its not blocked first ?

 

[Atlas]

Was blocked now clear, still no hot heater, bled system, seems to me the water pumps not circulating as heater blows cold only??????

 

[André4Renaults]

Just a thought, but the thermostat (or non-presence thereof..) might be the cause of the problem. As these cars don't have a temperature gauge it's sometimes difficult to work out the answer to these sort of problems. The following might help things warm up a bit:

Put all the hoses back, top up the antifreeze as required, put the heater controls onto "hot" & start the engine, topping up the radiator as required when the air bubbles come through. As the engine warms up the top hose will warm up first and when it becomes too hot to hold comfortably the hose to the heater should also warm up. Assuming the air has all been bled the heater pipe should warm too, although not as quickly as the radiator top hose. If it doesn't could it be that the heater controls are damaged or broken and that the valve is not allowing the hot water through? If the car can be driven around happily I'd have thought the water pump is working properly, or the car would have overheated by now. Bleeding car heater systems can take AGES and often cannot be done properly without allowing the system to become pressurised by getting up to operating temperature first.

 

[Cyprus Andy]

It could be a failed thermostat that has failed in the closed position ? If you remove the radiator capand heat the engine up to full temp you should be able to see the water circulating if the thermostat is opening when you put some revs on the engine.....if you do not see the water moving i the rad it is probably the thermostat remaining closed.
When I bled the system I took the expansion bottle off the inner wing and raised it higher than the bleed valve with rad cap off and got it bled through no problems.
As a failed thermostat can cause all kinds of problems I removed mine and fitted a Temp gauge to keep an eye on how it was running, along with an oil gauge. It runs at 80C when up to operating temp and never rises above that and gets about 50lbs oil pressure in 4th gear and 60lbs under high revs so I am happy with that.

 

[Atlas]

I've tried bleeding with raised expansion bottle, but not with rad cap off 1st job tomorrow Thanks Andy

 

[Atlas]

Thanks Andrew, I have a new thermostat in situ, I'll check again as mentioned. 1st job tomorrow.

 

[Geoff in the Gully]

Have you checked that the hose to the heater themselves are clear?
I've just bee through a similar issue with the heater and found, eventually, that the outlet from the waterpump had been sealed off with some form of metal filler.
Took ages replacing the waterpump - hope this isn't your problem but worth a check.

 

[Atlas]

Hi Geoff, I've circulated through the heater pipes, the heater pipes are not getting hot, I've tried bleeding I get occasional bursts of water but not continuous, there doesn't seem to be much flow from the pump although this new, belts are firm, might be a bleeding issue buts it's trying.

 

[André4Renaults]

Assuming the thermostat, water pump and pipes are all on order & functioning correctly, try this....

Put everything back together & put a funnel into the overflow pipe that normally runs into the top of the radiator from the expansion tank. Top up with the requisite mix of antifreeze & distilled water and stand by with a jug of pre-mixed antifreeze/distilled water. Tie the funnel to the open bonnet at a point higher than any part of the cooling system so that you can easily top up the funnel. Start up the car and run it until the engine runs on tick-over without the choke, which is the best indication that the engine's reached its operating temperature. Ensure the heater controls are set to hot & that the fan, if fitted, is switched on, directing heat to the windscreen. Slide the driver's window open, so you can easily check for warm air from the vents. Check that the radiator top & bottom hoses are hot, indicating that the water is circulating through the radiator. Now, from within the engine bay, operate the throttle & increase the engine's revs and watch for bubbles and any drop in the level of water in the funnel, which indicates air being released from the pipes. This could take anything up to 15 minutes of revving, topping up, massaging the pipes and putting one's hand on the screen heater vent to feel for warmth.

Once you're satisfied that no further air bubbles are coming up from within the engine, if there is STILL no heat from the heater, connect the overflow pipe from the radiator to the expansion tank (as it should be when the car's running normally) fill the expansion tank to the correct level, drop the bonnet & go for a long drive over a decent distance. This will allow the cooling system to become pressurised & should force water through to the heater matrix and push any residual airlocks through to the expansion tank.

Believe me, these problems can take AGES to fix. More advice by phone if you PM me.

If you're reading this in Southwold, I recommend a pint (or 4!) of Adnam's "Broadside" bitter, while thinking what to do next. Happy memories of the town & surrounding area.....

 

[Geoff in the Gully]

You should also open the heater bleed and leave it open until you get a nice steady jet of water with not bubbles.
It's the little hose sticking out of the firewall just below the gear shift shaft

 

[Atlas]

Looking good Andrew, made progress today, I have lifted the expansion bottle way up high and have a flow through the bleed hose... Saving more for tomorrow. Been in the Harbour inn had 3 pints of Adnams bitter, might try some in the rad. Cheers I'll keep you posted.

 

[mr-reno-139]

it is possible that the matrix is partially blocked but will still allow a flow but preventing heat from getting into the car
if all else fails and you don't fancy fitting a new matrix i have had quite a lot of success on various renault using descaler
if you disconnect both heater pipes from engine end flush though with a garden hose drain by blowing through 1 pipe
finally raise both pipes as high as possible and phil with descaling solution available from hardware shops use a funnel wedged in hose
leave overnight obviously making sure heater tap is on finally rinse through refill and bleed

 

[Atlas]

Thanks Reno, I've drained system and filled with distelled water, blown out hoses, removed lots of scale, I'm getting close to having heat.

 

[jjad]

Glad you're getting there :¬)

Nice picture, but I can tell it's not Southwold

 

[Atlas]

The latest, tried all avenues, i now have warmth but not heat, so I'm putting it down to corroded blocked matrix, so a soak down the pipes with de-scaler ?

 

[André4Renaults]

Make up a LARGE amount of "Kilrok" solution; you can buy this in Robert Dyas (other hardware stores are available....) Connect extension hoses to both pipes that run to & from the heater matrix and, keeping them both above the level of the matrix, pour the Kilrok solution into the matrix, allowing it to remain in the matrix. It works much better if it's hot when it's poured into the matrix and will froth up as it dissolves the "crud" from the matrix. The longer it's left, the better it works. Thoroughly rinse out afterwards & see if it's any better.... Repeat if necessary.

If de-ionised (distilled) water is used this build up of calcium is reduced and almost eradicated.

 

[mr-reno-139]

Great minds think alike that's what I posted above
I have also used air blow nozzle very carefully due to it not being nice on skin eyes paintwork etc and let a SMALL amount of pressure to bubble it's way through system this will agitate any debris in matrix
repeat in both directions

 

[Atlas]

Tried kettle de-scaler... Plan b "Kilrok"