13 replies to this topic

[JackBeard]

Hey guys/gals.

 

I'm still pretty new to the Mini world, so I thought I'd ask some experienced people to point me in the right direction.

 

My car's heater hasn't worked since I bought the car. There's no life in it whatsoever.

 

Seeing as winter is fast approaching, I just want to know where would be a good place to start checking?

 

Many thanks,

 

Jack

[Hrimfaxi]

First place i'd check, would be the fuse.

Haven't got my Haynes to hand, so couldn't tell you which number fuse it is though sorry.  

[sonikk4]

Switch or the fuse are common failure points so check these out first. Also it could be an earth problem as well.

[AVV IT]

Does it not produce heat, or not blow air? as these are too separate problems. The classic mini heater circulates hot coolant from the engine through a small radiator inside the heater called a matrix to produce the heat, a separate fan/blower then pushes air through the matrix to force the warmth of the heater and into the car. Unless there is a problem with both systems, then the heater will produce heat even if the fan/blower isn't working and the fan will blow cold air, even if there is a problem with the heater circuit.

 

If the fan/blower doesn't work then it's an electrical problem. If it's a fuse then your window wipers and washers probably wont work either, as on most minis they tend to share the fuse with the heater blower. (from memory I think it's the third fuse down in the fuse box). As above it could also be a faulty switch (easily tested by taking the wires off the back of the terminals on the back of the switch and joining them together), or a connection problem. If you drop the front of the heater down, by undoing the two screws that hold it into the lower dash rail at either end of the centre switch panel, you should find a wire coming out of the top of the heater and joining into the loom. Check this connection as it's common for it to get disturbed if the heater is ever moved to replace choke cables etc.

 

If the heater doesn't actually produce any heat, then it could be a number of issues with the heater circuit, including a faulty valve/heater tap, a blockage in the matrix, or an air lock, but let us know which sort of problem you're having.

[MiniMonty]

As above - but just to clarify for a newbie - when AVV IT says "The classic mini heater circulates hot coolant"

this means the water you pour into your radiator which circulates around the engine and cools it (therefore "coolant").

This liquid becomes hot enough to be worth using as a way of heating the interior (the cabin you sit in).

 

It's done by passing the hot liquid through a pipe from the engine into the heater assembly, through the "matrix" (where it heats thin metal pieces)

and then out and back into the engine. 

 

As the thin metal pieces heat up a fan behind them blows into the cabin and moves the heat from the "matrix" of thin metal pieces into the cabin. 

 

The Matrix in the heater (the maze of thin metal bits) in notorious for becoming rusty and needs to be swapped out every now and then (especially if you buy a car where it hasn't been done for a while). 

 

Read the post from AVV IT again and see which problem you have - solve them in order.

[alicetheauto]

There is also a "tap" on most minis under the bonnet either on the top of the engine or inline in a black water hose. Make sure this is open else the hot water won't go through to the car.

[JackBeard]

Yeah it's definitely not the fuse as my wipers work.

 

The heater box itself seems to get warm when driving, but cold air only seems to feed through the vents, regardless of whether the switch is on or off. I just put that down to bad insulation.

 

I'll check the switch like you said and then report back.

 

Thanks

[some1158]

Yeah it's definitely not the fuse as my wipers work.

 

The heater box itself seems to get warm when driving, but cold air only seems to feed through the vents, regardless of whether the switch is on or off. I just put that down to bad insulation.

 

I'll check the switch like you said and then report back.

 

Thanks

 

I may be misreading this but you know the vents at the sides aren't connected to the heater...?

[mattdc2r]

There was something in one of the mini magazines recently,'a heater that wasn't Plummer in to the cooling system. It was just an electric heater. Not sure how good it would be, or how efficient it would be.
Might be worth looking in to though.

[JackBeard]

My bad, as I said, I'm new to this.

 

The heater unit is producing heat, just not blowing it. So I assume it is an electrical fault somewhere (I shall inspect).

 

For the sake of sounding like a noob once again, what are the side vents there for if they're not connected to the heater? All they seem to do is feed ice cold air into my face!

[mab01uk]

My bad, as I said, I'm new to this.

 

The heater unit is producing heat, just not blowing it. So I assume it is an electrical fault somewhere (I shall inspect).

 

For the sake of sounding like a noob once again, what are the side vents there for if they're not connected to the heater? All they seem to do is feed ice cold air into my face!

 

Remember the Mini is basically a primitive 1950's designed car, on early models the heater was only an option ! The heater blows out hot air to the windscreen vents and front footwells depending on the control lever setting the air flaps. The fan switch boosts the hot/cold airflow, either 1 speed or 2 speed on late Mini's. There is a push/pull knob on the dash switch panel which controls the flow of hot water through the heater via a cable operated valve. The dashboard eyeball vents only feed fresh air when opened at whatever the outside air temperature is. So it is no A/C climate control system.......unless you buy a Wood & Pickett conversion maybe.

Edited by mab01uk, 09 November 2013 - 05:47 PM.

[JackBeard]

Thanks for clearing that up :). My right vent doesn't close, so I need to take a look at that, or start wearing gloves!

[some1158]

Thanks for clearing that up :). My right vent doesn't close, so I need to take a look at that, or start wearing gloves!

 

Sounds like a plan.  The vents are pretty good at demisting the car in winter (once you're moving) and the stream of air in summer is essential for cooling passengers!

[MiniMonty]

JackBeard, when you say "the heater is producing heat just not blowing it"

Be clear about this:   

the heater doesn't actually "produce" heat or heat anything up - there is no heating element in your heater (it's not a toaster).

It's the hot water that flows around the engine (and then in and out of the heater that provides the heat - that water flows through a radiator (the matrix)

inside the heater unit which gets hot (because the water is hot) then the fan blows air over that matrix and into the car. 

The "heater" in a Mini is really just a fan blowing over some water pipes and a small metal radiator all wrapped up in a box.

 

Sounds like you need to just service the whole unit - no big thing - get some screwdrivers (and a bowl) and take it to bits.

If you need full instructions on how to do it DON'T BE SHY - go to the technical section and ASK.

You wil have LOTS of replies. This is what the forum is for. 

 

99% of people on this forum have asked a "how do I" question in the technical section and the only reason there is so much knowledge

on here is that so many people have done those jobs, got them right and wrong and are ready to share the wisdom and experience.

 

DIVE IN. Let the forum work for you.

 

Ask a "how do I" on the technical forum and fix your heater - it's November, get some screwdrivers...

 

Best wishes

Monty