Vectra 55 1.8 SRi Blowing hot and cold simultaneously

DizzyEnvelope

Hi
I have a 55 Vectra, and recently had temperature problems.

It had been losing water and a couple of weeks ago, during -º temps started blowing cold air when set to hot, and engine overheating. Filled expansion tank with correct concentrate of antifreeze - Continued blowing cold and overheating!

Took to Garage who suggested maybe radiator maybe gasket, min £200, plus investigation fees!!

Took elsewhere, changed radiator, and Thermostat - still blowing cold and overheating.

Called out RAC, excellent! - had airlock in system, RAC sorted that, no more overheating, but still no hot air in car. RAC suggested perhaps heater switch control panel may be faulty. No fault on Gasket.

Tried another control panel - no difference.

Flushed out heater matrix for 3o mins, and now the drivers side of heating is sort of working - but still blowing cold on passenger side

Any ideas please???

forgotmyname

Heater matrix clogged up?

Are the pipes to the heater getting hot? Down the back of the engine where they go through the bulkhead into the car.

Are any valves controlling the flow to the internal heater working and open?

If the heater matrix is getting hot then it maybe an airflow issue. The splitter for hot/cold air maybe stuck in the cold position.

Strider590

Might be bad/wrong thermostat, if stuck open you'll get no heat in this weather.
Does it blow warm air when left to idle/stationary?

You can also check the stat by grabbing the hose from it to the radiator, if the hose is cold after a drive, then the stat is at fault.

spacey2012

Vauxhalls have a heater valve thingymybob, two pipes in one out, they are supposed to divert warm water straight to the heater instead of the radiator, then when hot switch it to all, when they go wrong, as they do, you get either random mix of hot and cold without any justice, or nothing in the heater, they let out steam when !!!!!!ed and empty the expansion tank, shut the water off and boil the engine.
A real pain !
I trust they checked it before replacing the expensive bits ?

DizzyEnvelope

Hi there,

thanks all for getting back to me:-

forgotmyname - yes the pipes are all hot, and the control panel changes the valve position when turned, so presume this is the splitter and is working ok.

Strider590 - The thermostat was changed by mechanic then checked by RAC - all well there, and again all pipes are hot.

spacey2012 - feels like absolutely everything's been checked, prodded and double checked - really frustrating now, must be something blocking the hot air getting through, esp if the air is starting to get luke warm on one side.

Someone said to try using Soda Crystals while flushing out the heater matrix again to see if that helps to dislodge whatever???

Just seems so strange, air seems to be coming through as strong as ever, just bloomin cold!!!

Thanks for the advice, think will try to reflush the heater matrix again, when the rain stops!!

spacey2012

Check to see if it has a distribution valve, if it has climate control, it splits the heater left and right as well.
If it has, get it replaced, the test involves a bucket of hot water, hammer and a tea towel, which you would need a new one anyway,
Basically they are a twin thermostat inside a 3 way hose coupling, that closes when hot and opens when cold and vice versa for the second valve , once faulty, any variation is possible.
Usually around £10-£20 for the part and about a minute to fit, or two if you can not find it at first.
If it has one and they have not replaced it with a new one given these symptoms, they have, well lets put it simply cocked up !

DizzyEnvelope

Thanks Spacey2012 - will give that a go

red_eye

forgotmyname wrote: »

Heater matrix clogged up?

Are the pipes to the heater getting hot? Down the back of the engine where they go through the bulkhead into the car.

Are any valves controlling the flow to the internal heater working and open?

If the heater matrix is getting hot then it maybe an airflow issue. The splitter for hot/cold air maybe stuck in the cold position.

or the polen filter growing a dead tree