precat heater

[SteveSPG]

with the blowers on the heater, i seem to have ots of air around the passenger footwell that isnt coming out of the blowers. if i stick my hand up the left hand side of the matrix, i can feel air blowing around what i presume is the side of the heater matrix.

does anyone have any decent pics, or any ideas what i need to look at to determine if there is anyting loose???

seems to be a recent thing, as i am sure that i had better airflow before through the vents.

thanks

[stevesprint]

Steve
The biggest issue is the front of the heater matrix box, where the hoses connect, is not sealed to the inner wing, in fact there is a big hole where the hoses pass into the inner wing. Cold air also escapes into the passenger’s footwell from the old and perished seal across the top of the box and through the cable holes without grommets.

Steve, I made an air box to mount the blower directly to the matrix as you can see in the pictures below.

If you use your car in the winter with a passenger it’s certainly worth the effort and you'll find its child’s play compared to your LS installation!!!!!

Should you have any further questions please do not hesitate to contact me.

Cheers
SteveSprint

Patent pending


Door seal across the top


It's a very tight fit (I had to trim the indicator to make room)


Griff 500 Panel (actually I don't like to admit its a chimmy panel)

[SteveSPG]

thanks....i wonder is yours the same as a pre cat setup?

ive not looked too closely, but im not sure mine looks the same, though i could just need to pull the dash off and see.

[stevesprint]

Steve
Mine is a precat with the original blower under the headlamp which is now disconnected.
It may look different because the fuse board and battery are removed and I've moved my blower to the same postion as the 500's. Also I've added the extra doors seals across the top and bottom of the air box.
Cheers
Steve Sprint

[Pagey430]

wow, that looks a neat solution, bet you get some decent airflow through the vents! I see 'patent pending' are you planning to produce? I could be interested in one

[SteveSPG]

Ok, the penny drops..(I think).so that is a "new" 500 fan placed in the space where previously were just air channels, so any blown air is forced through the heater matrix, is that correct?

And in addition you've made an additional shroud to mount it, and fitted a 500 side panel....interesting, and worth persuing

Edited by SteveSPG on Thursday 28th March 19:32

[stevesprint]

Patent pending was only a joke, sorry. You are welcome to copy it.
Cheers
Steve

[stevesprint]

Yes Steve that's correct, the Precats rely on an air tight wing. Yes the fan is a second hand one off a Nova which is the same as the original Griff Precat & 500 fan.
Steve

[FactBV]

SteveSPG said:

Ok, the penny drops..(I think).so that is a "new" 500 fan placed in the space where previously were just air channels, so any blown air is forced through the heater matrix, is that correct?

And in addition you've made an additional shroud to mount it, and fitted a 500 side panel....interesting, and worth persuing

Edited by SteveSPG on Thursday 28th March 19:32

This is very interesting for me (sad but true). My fan in the near side forward wing has seized and I have a new one to fit. However, there does not seem to be a shroud around it as I can just get my fingers on to the impeller. I understand that the fan actually pressurises the inner wing, some of which finds its way into the heater box, so this looks good although a bit drastic. I heard that another way around it is to put a duct all the way from the fan, through the wing and into the heater box. Although to be honest tracing the vent and heater pipes generally, the whole system doesn't seem to make sense

[Barreti]

Peter,

What you are going to find in the void under the headlight is something like this


Air is sucked in underneath through a roughly cut hole in the inner wing. It is then pushed into the upper void which is sealed by the skirt and can only escape by going through the vents via the heater matrix.
This is the theory. In practice it seems to go anywhere else but through the vents.

There are 2 solutions I know of which don't involve fitting a motor directly to the matrix as Steve has done.
One is to run a pipe from the motor over the wing and directly into the matrix box. Ant did this and the results are supposed to be staggering, there is at least one thread on here about it.
The second solution is the one I did, again after reading about it on here, whereby you do away with the skirting and fix a pipe to the top of the motor and seal it into the wing void over the wheel. Its made a huge difference to my heater - in that I now actually have heat

Like this


Here are the bits I used. The Round to Rectangular Adaptor is the white thing on top of the motor and the Flat to Round Adaptor is the bit which is siliconed into the wing void then the gap around it is sealed using expanding foam.


And you may find your motor is actually OK, but the power connector looks like this and just needs a good clean

Edited by Barreti on Friday 29th March 06:02

[FactBV]

Barreti said:

Peter,

What you are going to find in the void under the headlight is something like this


Air is sucked in underneath through a roughly cut hole in the inner wing. It is then pushed into the upper void which is sealed by the skirt and can only escape by going through the vents via the heater matrix.
This is the theory. In practice it seems to go anywhere else but through the vents.

There are 2 solutions I know of which don't involve fitting a motor directly to the matrix as Steve has done.
One is to run a pipe from the motor over the wing and directly into the matrix box. Ant did this and the results are supposed to be staggering, there is at least one thread on here about it.
The second solution is the one I did, again after reading about it on here, whereby you do away with the skirting and fix a pipe to the top of the motor and seal it into the wing void over the wheel. Its made a huge difference to my heater - in that I now actually have heat

Like this


Here are the bits I used. The Round to Rectangular Adaptor is the white thing on top of the motor and the Flat to Round Adaptor is the bit which is siliconed into the wing void then the gap around it is sealed using expanding foam.


And you may find your motor is actually OK, but the power connector looks like this and just needs a good clean

Edited by Barreti on Friday 29th March 06:02

Really helpful, thanks very much. So that silver pipe now only vents into the rear section of the wing, which is sealed around the silver pipe and the rest is the same as standard? Was it a lot more trouble to step the pipe diameter down and insert it directly into the the heater box as Ant did? Also, would I be right in saying that, at least in theory, the fan also serves the cold air vents, via the flexible pipe that comes from out of the passenger footwell near side and up under the dash. Thanks again.

[FactBV]

FactBV said:

Barreti said:

Peter,

What you are going to find in the void under the headlight is something like this


Air is sucked in underneath through a roughly cut hole in the inner wing. It is then pushed into the upper void which is sealed by the skirt and can only escape by going through the vents via the heater matrix.
This is the theory. In practice it seems to go anywhere else but through the vents.

There are 2 solutions I know of which don't involve fitting a motor directly to the matrix as Steve has done.
One is to run a pipe from the motor over the wing and directly into the matrix box. Ant did this and the results are supposed to be staggering, there is at least one thread on here about it.
The second solution is the one I did, again after reading about it on here, whereby you do away with the skirting and fix a pipe to the top of the motor and seal it into the wing void over the wheel. Its made a huge difference to my heater - in that I now actually have heat

Like this


Here are the bits I used. The Round to Rectangular Adaptor is the white thing on top of the motor and the Flat to Round Adaptor is the bit which is siliconed into the wing void then the gap around it is sealed using expanding foam.


And you may find your motor is actually OK, but the power connector looks like this and just needs a good clean

Edited by Barreti on Friday 29th March 06:02

Really helpful, thanks very much. So that silver pipe now only vents into the rear section of the wing, which is sealed around the silver pipe and the rest is the same as standard? Was it a lot more trouble to step the pipe diameter down and insert it directly into the the heater box as Ant did? Also, would I be right in saying that, at least in theory, the fan also serves the cold air vents, via the flexible pipe that comes from out of the passenger footwell near side and up under the dash. Thanks again.

By the way it is the fan that has seized, I could hardly turn it with my fingers, but that plug doesn't look great as you say.

[Barreti]

FactBV said:

So that silver pipe now only vents into the rear section of the wing, which is sealed around the silver pipe and the rest is the same as standard?

Yep, exactly right. And I threw away the skirting which stand like a carpark stairwell.

FactBV said:

Was it a lot more trouble to step the pipe diameter down and insert it directly into the the heater box as Ant did?

Yes, because you can't actually get to the back of the heater matrix without taking it out and you certainly can't get your hand into the void above the wheel arch.
I get pretty good heat air flow through mine now, but Ant used to say his whistled if he shut the vents!
In terms of cooling, this is only done by shutting off the hot water feed into the matrix. The air flow is the same for both, it just runs over a cold matrix when you want cold air.
So if you get air up there and have the hot water valve set up correctly above the battery you will be OK.

FactBV said:

Also, would I be right in saying that, at least in theory, the fan also serves the cold air vents, via the flexible pipe that comes from out of the passenger footwell near side and up under the dash. Thanks again.

This reminds me, check the fitting of the pipe from the inner wing.
I found it ill fitting and always coming out. I fettled it to fix that and cut the end of the pipe at a 45deg angle so air being forced through the inner wing would be 'scooped' as it hit the pipe. This seemed to help a lot.

[FactBV]

Barreti said:

FactBV said:

So that silver pipe now only vents into the rear section of the wing, which is sealed around the silver pipe and the rest is the same as standard?

Yep, exactly right. And I threw away the skirting which stand like a carpark stairwell.

FactBV said:

Was it a lot more trouble to step the pipe diameter down and insert it directly into the the heater box as Ant did?

Yes, because you can't actually get to the back of the heater matrix without taking it out and you certainly can't get your hand into the void above the wheel arch.
I get pretty good heat air flow through mine now, but Ant used to say his whistled if he shut the vents!
In terms of cooling, this is only done by shutting off the hot water feed into the matrix. The air flow is the same for both, it just runs over a cold matrix when you want cold air.
So if you get air up there and have the hot water valve set up correctly above the battery you will be OK.

FactBV said:

Also, would I be right in saying that, at least in theory, the fan also serves the cold air vents, via the flexible pipe that comes from out of the passenger footwell near side and up under the dash. Thanks again.

This reminds me, check the fitting of the pipe from the inner wing.
I found it ill fitting and always coming out. I fettled it to fix that and cut the end of the pipe at a 45deg angle so air being forced through the inner wing would be 'scooped' as it hit the pipe. This seemed to help a lot.

Excellent, just what I need, thanks for taking the time to explain that.