Better half has '65 plate 2ltr diesel but gets very little, if any heat through the vents. Temp gauge registers and the coolant levels good.

Things to start checking please?

Battery state of charge.  These engines produce very little waste heat, especially at this time of year.  There is an additional electric heater inside the car to provide heat before the coolant reaches temp.  That gets switched off when the battery charge is low.

It may also have a slightly leaky thermostat, but even with a good stat I would expect it to take 10-15 mins driving to get hot air through the vents around 0c ambient.

1 minute ago, TomsFocus said:

These engines produce very little waste heat, especially at this time of year. 

I know, tell me about it !!

My own 2.0 Ecoblue Focus can easily take 30 minutes to reach a normal operating temperature. The only way I find to get the cabin warm in a sensible time is to select "Hi" on the temp dial, and set the heating to either face vents or floor.

Leaving the climate control set in 'auto' as I normally leave it seems to direct what little heat there is to the screen with little or nothing to the rest of the car. The heater on my Mk1 Escort used to be quicker and hotter 🤣 

2 minutes ago, unofix said:

... The heater on my Mk1 Escort used to be quicker and hotter 🤣 

I often read about poor heating on 'new' cars. My 20 year old Mk2 chucks out hot heat after just a few minutes of driving, even on icy mornings, and with fan on high, temp gauge on max, it'll clear an iced windscreen in a couple of minutes too. They apparently don't make them like that anymore 😂

6 hours ago, TomsFocus said:

Battery state of charge.  These engines produce very little waste heat, especially at this time of year.  There is an additional electric heater inside the car to provide heat before the coolant reaches temp.  That gets switched off when the battery charge is low.

It may also have a slightly leaky thermostat, but even with a good stat I would expect it to take 10-15 mins driving to get hot air through the vents around 0c ambient.

Definitely no heat prior to engine actually warming up or even when warm 😞

1 hour ago, Stevep999 said:

Definitely no heat prior to engine actually warming up or even when warm 😞

If there's no heat inside when the coolant is hot then that would suggest a fairly major issue.  If possible, I would test the coolant temp with an OBD2 reader to see how hot it really is.

On 1/14/2025 at 5:34 PM, TomsFocus said:

If there's no heat inside when the coolant is hot then that would suggest a fairly major issue.  If possible, I would test the coolant temp with an OBD2 reader to see how hot it really is.

so engine oil temp and coolant temp rise as per expected viewed through OBD port using carista

56 minutes ago, Stevep999 said:

so engine oil temp and coolant temp rise as per expected viewed through OBD port using carista

How hot is the coolant actually getting?

If it is reaching 80c+ then the next step is to check it's circulating through the heater matrix pipes.  You can feel both pipes in the engine bay if you can access them.  Otherwise get into the passenger side footwell and touch the pipes there.  They should be the same temp as the coolant so take care not to burn yourself.

If hot coolant is circulating through the matrix then that only leaves a flap issue, with the air diverter flap not being moved to pass air over the matrix before reaching the vents.

47 minutes ago, TomsFocus said:

How hot is the coolant actually getting?

If it is reaching 80c+ then the next step is to check it's circulating through the heater matrix pipes.  You can feel both pipes in the engine bay if you can access them.  Otherwise get into the passenger side footwell and touch the pipes there.  They should be the same temp as the coolant so take care not to burn yourself.

If hot coolant is circulating through the matrix then that only leaves a flap issue, with the air diverter flap not being moved to pass air over the matrix before reaching the vents.

 

4 minutes ago, Stevep999 said:

98c!?  That's on the verge of overheating.  The heaters should definitely be hot in that case.  The radiator fan should also be running.

Not convinced that data is reliable though.  I've never seen oil temp at 103c on my own 2.0 diesel engine.

 

17 minutes ago, TomsFocus said:

98c!?  That's on the verge of overheating.  The heaters should definitely be hot in that case.  The radiator fan should also be running.

Not convinced that data is reliable though.  I've never seen oil temp at 103c on my own 2.0 diesel engine.

 

Oh. I'll check the pipes this afternoon. Should I be able to reach them with out removing anything in footwell ,??

7 minutes ago, Stevep999 said:

Oh. I'll check the pipes this afternoon. Should I be able to reach them with out removing anything in footwell ,??

Yes hopefully, although I haven't seen a Mk2 S-Max footwell.  (I'm assuming it's Mk2 being a late 2015 model)

 

On 1/16/2025 at 1:55 PM, TomsFocus said:

Yes hopefully, although I haven't seen a Mk2 S-Max footwell.  (I'm assuming it's Mk2 being a late 2015 model)

So, can't reach the pipes in footwell 😞

Atttached are some temps from Forscan. The internal temp sensor was disabled in forscan. When I enabled it got appropriate tremp reading in Forscan.

Guess first root is to get the thermostat on engine changed ? 

 

1 hour ago, Stevep999 said:

 

So, can't reach the pipes in footwell 😞

Atttached are some temps from Forscan. The internal temp sensor was disabled in forscan. When I enabled it got appropriate tremp reading in Forscan.

Guess first root is to get the thermostat on engine changed ? 

 

Yes, if the coolant is only reaching 63c, that won't be enough for hot heaters.