Heater matrix

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HenryM3
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Tue Oct 13, 2020 9:32 pm

What does the diaphragm do then, is it to stop water getting to the solenoid
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Brianmoooore
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Tue Oct 13, 2020 9:54 pm

martauto wrote:
Tue Oct 13, 2020 2:31 pm
I would have heat for the first time in my car ?
Didn't realise that your problem was no heat at all. It's unusual for a valve to fail shut, unless the heater hoses are the wrong way around, when the flow of water can hold it closed. Do you know that the problem is with the valve and not the matrix?
The purpose of the diaphragm is to block the hole that the coolant flows through when required, and cut off all flow to the matrix. It also has the secondary purpose of keeping coolant out of the motor.
HenryM3
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Wed Oct 14, 2020 10:46 am

Maybe a dumb question but if opened up can the diaphragm be replaced/substituted.
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martauto
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Wed Oct 14, 2020 1:06 pm

Brianmoooore wrote:
Tue Oct 13, 2020 9:54 pm
It's unusual for a valve to fail shut, unless the heater hoses are the wrong way around, when the flow of water can hold it closed.
When I first got the car the heater hoses from the engine were on the wrong way around and the aux water pump had expired so maybe this could account for it ?

Mart.
Only the E46 cab left now.
Just got too old.
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loogie1
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Fri Oct 16, 2020 1:55 pm

Sanchez wrote:
Tue Oct 13, 2020 11:47 am
loogie1 wrote:
Thu Oct 08, 2020 11:09 am
Thinking these may fit. will strip my valve to measure o-ring size, when i get near a garage.
https://www.ebay.co.uk/itm/M3-3mm-A2-ST ... SweChcrf~5
Iirc 45mm length required for bolts.

30mm large oring and the 2 smaller 17.9mm required.
Thank you,
"2 smaller" Thought there was only one?
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loogie1
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Fri Oct 16, 2020 2:09 pm

Brianmoooore wrote:
Tue Oct 13, 2020 9:54 pm
martauto wrote:
Tue Oct 13, 2020 2:31 pm
I would have heat for the first time in my car ?
Didn't realise that your problem was no heat at all. It's unusual for a valve to fail shut, unless the heater hoses are the wrong way around, when the flow of water can hold it closed. Do you know that the problem is with the valve and not the matrix?
The purpose of the diaphragm is to block the hole that the coolant flows through when required, and cut off all flow to the matrix. It also has the secondary purpose of keeping coolant out of the motor.
Ahhh, My diaphram is shot (non existent), i was hoping I could reassemble the unit and it would remain water tight but you say the diaphram keeps the "coolant out of the motor". Am i still going to have a leek? I hadn't considered coolant entering the motor! I was lloking at a nice flush face for the oring to seal against was forgetting the diaphram plunger opening to the motor! Damn. Will need to source a replacement valve afterall?
Better to find out now i suppose.
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Brianmoooore
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Fri Oct 16, 2020 2:22 pm

A flat plate bolted in place of the motor will keep the coolant in.
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loogie1
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Fri Oct 16, 2020 2:35 pm

Brianmoooore wrote:
Fri Oct 16, 2020 2:22 pm
A flat plate bolted in place of the motor will keep the coolant in.
Yes, just read your previous comment, with Gasket/oring. Utilising the o ring would require some machining of a plate? be neat but flat plate and gasket would suffice?
Thank you.
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loogie1
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Fri Oct 16, 2020 4:26 pm

Sanchez wrote:
Sun Jun 21, 2020 8:30 pm
I changed the large 30mm oring out to stop the leak and replaced the 2 17.12mm ornings. All done and leak free. My threads on the zone Facebook page as my flickr pictures don’t seam to work here.
Just joined the Zone FB. do you have a link? cheers
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Brianmoooore
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Sun Oct 18, 2020 11:30 pm

martauto wrote:
Wed Oct 14, 2020 1:06 pm
Brianmoooore wrote:
Tue Oct 13, 2020 9:54 pm
It's unusual for a valve to fail shut, unless the heater hoses are the wrong way around, when the flow of water can hold it closed.
When I first got the car the heater hoses from the engine were on the wrong way around and the aux water pump had expired so maybe this could account for it ?

Mart.
It's possible, I suppose, You could try adding a bit of pressure to the flow by disconnecting the heater hoses at the bulkhead (pull them off quickly, and tie them up to a piece of string from the wiper spindle). You won't loose much coolant, then hold a garden hose onto the bottom stub pipe, and see if water flows readily out of the top stub. Don't go above 2 bar or so of pressure.
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Sun Aug 13, 2023 9:43 pm

Good day. I have a problem with my 325is. I did a full restoration. All items were replaced. Radiator. Thermostats. Heater valve. Heater core. All piping.

The heater rotary knob on the dash panel was also defective , and replaced (this knob alone was USD250)

When I leave the temperature control knob on full cold , I get environmental temperature air into cabin. When I turn on full heat , I get hot air

The problem is in between. I do not get “blended” air temperature. What can the problem be ? It’s either too hot or too cold , and I cannot regulate it to give the desired temperature
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Brianmoooore
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Sun Aug 13, 2023 10:20 pm

When the temperature knob is at fully cold, an electrical switch is closed, supplying power to an electric water valve, which shuts off all flow through the heater matrix.
When the knob is turned just a few degrees from fully cold, the switch opens,, the water valve opens, and full flow passes through the heater matrix.
The rest of the rotation of the knob operates a Bowden cable, which should control an air diverting flap inside the heater body. With the flap fully one way, air passes from the fan directly to the vents without passing through the heater matrix. With the flap fully the other way, air from the fan is all forced through the matrix before exiting the vents. At flap positions in between these extremes, some air bypasses the matrix and some flows through it, mixing it to the desired temperature.
It sounds like your flap is permanently in or near the position where all air is forced through the matrix, so you need to check whether the inner and outer of the cable are fixed and adjusted correctly, and whether the flap control is broken or stuck in any way.
The above assumes you do not have the rare climate control option, which controls temperature in a different way.
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flybynite
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Mon Aug 14, 2023 7:15 am

You're back :clap: we were all wondering where you went 8O
Brianmoooore wrote:
Sun Aug 13, 2023 10:20 pm
The above assumes you do not have the rare climate control option, which controls temperature in a different way.
I have one that I am looking to put back instead of my old one. If you are back long-term I might give it a go!

Did aircon cars have this fitted too? I have one aircon set with the numbers round the dial where the others don't, it seems to be very different and I am struggling to fathom it out.
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BenHar
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Mon Aug 14, 2023 6:44 pm

Brianmoooore wrote:
Sun Aug 13, 2023 10:20 pm
When the temperature knob is at fully cold, an electrical switch is closed, supplying power to an electric water valve, which shuts off all flow through the heater matrix.
When the knob is turned just a few degrees from fully cold, the switch opens,, the water valve opens, and full flow passes through the heater matrix.
The rest of the rotation of the knob operates a Bowden cable, which should control an air diverting flap inside the heater body. With the flap fully one way, air passes from the fan directly to the vents without passing through the heater matrix. With the flap fully the other way, air from the fan is all forced through the matrix before exiting the vents. At flap positions in between these extremes, some air bypasses the matrix and some flows through it, mixing it to the desired temperature.
It sounds like your flap is permanently in or near the position where all air is forced through the matrix, so you need to check whether the inner and outer of the cable are fixed and adjusted correctly, and whether the flap control is broken or stuck in any way.
The above assumes you do not have the rare climate control option, which controls temperature in a different way.
I thought it was cleverer than that?

At about the mid setting it is supposed to put cooler air through the face level vents and warmer at foot level.

Ben
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Brianmoooore
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Mon Aug 14, 2023 7:13 pm

BenHar wrote:
Mon Aug 14, 2023 6:44 pm
I thought it was cleverer than that?

At about the mid setting it is supposed to put cooler air through the face level vents and warmer at foot level.

Ben
That's done by positioning the outlets in the heater box for the face vents closer to the bypass side of the flap than the outlets for the floor .
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BenHar
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Tue Aug 15, 2023 6:42 pm

Brianmoooore wrote:
Mon Aug 14, 2023 7:13 pm
BenHar wrote:
Mon Aug 14, 2023 6:44 pm
I thought it was cleverer than that?

At about the mid setting it is supposed to put cooler air through the face level vents and warmer at foot level.

Ben
That's done by positioning the outlets in the heater box for the face vents closer to the bypass side of the flap than the outlets for the floor .
Interesting, Thanks, Brian.

Good to see you back.

Ben
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