Heater not running hot, any ideas?

[redzed]

My heaters not running hot, I've fitted a new heater resistor so don't think it's that previous one didn't work at all and this one is meant to be a fully working unit. Anyway where should I start looking? Cheers guys for the advise as always

[peterzs]

is the water temp gauge on halfway???

Thermostat OK?

Air lock in the pipes?

Blocked heater matrix?

:w00t::w00t::w00t:

[talkingcars]

Air con or climate control?
Is it blowing any air?
Is the valve that controls the coolant moving?
(IIRC it is under the bonnet on the mk1 and in the heater box on the mk2).

[MG ZS STE]

Even on Hi?

[Dan1971]

I has cold air in a ZT-T V6 I owned a while back. Had an air lock. Bled the system, worked for a while and I sold it. A short while later it happened again - it had HGF.

Not doom and gloom by any means, but it is what happened to me.

[Mark S]

could be servo motor that opens that flap that directs air passed heater matrix.

[MG ZS STE]

Running the diagnostic would eliminate any servo issues. Is it hold the auto when turning the key starts the cycle?

[Skillen]

could be servo motor that opens that flap that directs air passed heater matrix.

Would the test mode see that?
I can't remember now if it would.

[MG ZS STE]

I'm sure it tests all the servos. You can hear them whirring away as it goes through the cycle.

[petet16]

For the self test, keep the auto button pressed and switch ignition to position 2.

The links and servos can be accessed from the drivers footwell, they're fixed to the side of the heater box so you should be able to see them moving as you change the temp setting and also as you change the direction of the air between screen and foot wells.

[redzed]

Air con or climate control?
Is it blowing any air?
Is the valve that controls the coolant moving?
(IIRC it is under the bonnet on the mk1 and in the heater box on the mk2 but it maybe the other way around).

Havent looked properly at it yet, will try tomorrow lunch hence the thread on here to give me some heads up before i try it. Its a v6 mk2, the aircon works, all speeds work fine and no heat even on full. Temperature gauge is fine too, hopefully its something simple! been waiting ages for this heater resistor as theyre rare as rocking horse *****. Dont think its that with the issue though.

[MG ZS STE]

Could either the internal or external temp sensor affect how hot the heater gets? Run the self diagnosis is the 1st check I'd do.

[petet16]

The internal one might, it has a little fan that draws air across the sensor, if it gets clogged with dust it could potentially cause a problem, when my external one was knackered it didn't seem to affect the max temp at all.

[redzed]

Could either the internal or external temp sensor affect how hot the heater gets? Run the self diagnosis is the 1st check I'd do.

howd you run a self diagnostic?

missed the other post earlier! ignore this question

[redzed]

The internal one might, it has a little fan that draws air across the sensor, if it gets clogged with dust it could potentially cause a problem, when my external one was knackered it didn't seem to affect the max temp at all.

do you know where the internal one is?

[petet16]

It's behind the little grill next to the atc display.

[redzed]

sorted! thanks for the help and advise. turns out it was the bracket which attaches to the motor to select the heat which had popped out see the photo (the blue bracket) dont know how that had happened but after a hour or so of playing i found it and now have heating!

[petet16]

Good news.

[redzed]

opps see pic attached

[talkingcars]

Pleased to help, glad it's sorted.