[Fixed] No Heat In Heater And High Idle Temps Post Prrt + New Rad?

[glitch]

FIXED FINALLY! - PRRT on Elise S2 111S with VVC engine and re-circulation pump plus factory oil cooler requires modification of the plumbing in order to get best performance and working heating!

 

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Had a PRRT fitted last year, when I got my car back from the garage heater didn't work anymore.

As it was a very hot summer never thought about it and then during the winter I figured I'd have a look and that i was the heater actuator. Actuator was actually working it turned out.

 

During the same time fitted a new alloy rad as well.

We had some issues initially with big air locks in the heater matrix preventing from warm water getting in but eventually it seemed alright. Driving the car yesterday however temps were fine driving (82-88 C, ambient temp 7-8C). but at idle rose very quickly and after a short drive while parking in the garage rose to 110 C before I switched off.

 

Here is a short summary of what has been done (copy pasting my mates text).

 

What ha been done:

1. Change of radiator.
2. Bled the system.

- Car getting hot at tick over and no heat from matrix.

3. Bled the matrix itself

- Car getting hot at tick over and no heat from matrix.

4. Flushed the matrix backwords and collected small amount of "dirt".
5. Filled the matrix and bled it separately.

- Car getting hot at tick over and no heat from matrix.

6. Sucked coolant through the heater return pipe on the left side of the car.
7. Bled the entire system.

- Heat from matrix and car not getting hot at tick over.
However, the heater return pipe is now the feed pipe to the matrix, left side of matrix hotter than the right side etc.
Very strange

8. Thought all was fine (except for the reversed circulation to the matrix), checked that the matrix got hot every time I've moved the car.

9. Test drive today.

- Car getting hot at tick over and no heat from matrix.


What happends if the PRRT thermostat doesn't work properly?
Could this cause this?

 

 

What really confuses us is that the heater feed hoses by the matrix and next to the engine remain cool, but the return actually gets warm?? Seems almost like heater matrix circuit is reversed?

 

[Martin R]

Did you remove the OE thermostat and replace with a dummy with no centre? If you did the PRRT is playing up IMO.

[Numbnutz]

If you increase the revs by 1000 does the matrix start to get hot? It could be a lazy water pump.

 

Feel the pipe under the drivers sill at the rear where the post thermostat hot water is pumped to the rad. Check how hot this is. Should be v hot if engine temp reads 90+.

 

Incidentally the heater matrix pipe feeds off this main pipe just before it goes into the sill. Check this is also v hot at tick over if not at higher revs.

 

If this all seems ok but still no heat, feel the heater matrix return pipe on the passenger side. (Thinner metal one I think) If cold - disconnect the heater matrix pipes an join together with a copper or metal pipe an see if it gets hot at tick over. If not there is something blocking its return - undo the return and block the engine side and feed the return back into the expansion bottle with a temp pipe.

 

If this is pushing hot water, the bock is somewhere in between.

 

See how you get on and report back.

[glitch]

Thanks numbnutz will try those things. Didn't notice a difference when revving. Drove the car spirited but still not the slightest heat coming out.

Radiator feed hose on rhd side gets hot but the take off feeding the heater does not get very hot at all.

And on the return side acutally the heater return metal pipe gets warm and the same at the front by the matrix. The feed side is cool and return warm?? Almost feels like the flow had been reversed?

 

oem thermostat should be removed but garage did this job and of course unless you donit yourself it is hard to be certain.

What would be typical symptoms of oe stat still in place?

[Numbnutz]

Is the hot cold heater control defo working? From what you say it sounds like hot water is not getting through the heater control valve. On most lotus elise these valves leak some hot/warm water that means your cold air isn't well cold.

 

You could mole grip the rubber heater return pipe and disconnect the heater feed after the heater control valve, and then before this, and see if it pushes water into a milk bottle. That may give a clue.

 

I would suspect this before a blockage, but as you have had a prrt fitted recently you should also suspect something is blocking the return in the engine bay.

 

If the return is blocked, water won't flow - hence taking the return off near the bottle or by the rad and seeing if it flows ok at this point.

 

Oem stat fitted if its working means the water in the engine gets up to 80-90' (forget the exact temp, but very hot to hold) before it starts feeding it to the rad to regulate the temp.

 

With the thermostat removed, engine water temp and rad temp should be similar and it will take more time to warm up, as lukewarm warm engine water will be fed to the rad.

 

So if the rad is getting warm/hot before the temp is displayed on the dash. Either your thermostat is stuck open, or its removed.

[glitch]

Heater control valve? Never heard of this?

I don't have AC and as far as I can see in the diagrams there is no heater control valve?

[Numbnutz]

The valve that controls whether your blowers are hot cold or warm.

 

forgot what it's called.

[glitch]

You mean the heater actuator? That is driven by a small rotor and moves the flaps in the heater assembly to either block hot air from heater matrix or to lead it into the ventilation.

Yes it works just fine, it was re-furbished while the clam was off and new rad was fitted.

With it in full hot position, you can access and touch the actual heater matrix which remains cold.....

[Numbnutz]

Sorry, I thought the earlier cars had a valve in there for some reason. I was going to put a valve in mine to prevent heat creep in summer.

 

Makes fault finding a bit easier then. Have you disconnected the water pipe as it returns back on passenger side yet and put a temp pipe in to feed it back into expansion bottle to see if it's flowing ok?

 

If it is . It must be blocked between here and the prrt / engine. Let us know.

 

Who supplied and who fitted the prrt?

Was it 2nd hand and if so was it checked and cleaned out before fitting.

 

The plumbing on my oem prrt is odd to look at, perhaps the routing is wrong and preventing correct circulation somehow.

[glitch]

Hi,

 

the PRRT is Elise Parts one.

It was fitted by Bennets, are garage here in Sweden which has the longest history of working on Lotus in the country (commercially active since the 80's). Having said that, Lotus is a rare sight here in our country so not exactly an everyday job for them either but they have installed a few PRRT over the years.

 

Not had time to look anymore into it, hopefully this weekend I'll have a few hours. 11 month old baby and car in friend's garage so I every hour with the car has to planned meticously

[Martin R]

Ring them up and ask if they removed / replaced the old stat would be my first move?    Good luck.

[Numbnutz]

I don't think it's a worry about the thermostat if the feed down the right to the rad is hot.

 

I'd get a water pipe map off seloc wiki and ask elise parts if they have instructions that you can check has been followed and ask them if they have had any similar issues with this kit. Email then now before the weekend.

 

My MY04 elise had a prrt as oem and it looked a strange setup - not an easy to make up affair.

 

I know what you mean about having stuff in another garage. My best bike is in my dad's garage and u know what old ppl are like if you want to nip around quick .. you feel obliged to talk to them.

[glitch]

My dear friend spent some time on his garage floor to measure temps .etc.

Now we are even more confused than before.....

#1 This is what the cooling circuit looks like from stock.

http://www.dykarna.nu/fotoalbum/27072/335572.html

#2 These are some pictures of the PRRT install
http://www.dykarna.nu/fotoalbum/27072/335570.html
http://www.dykarna.nu/fotoalbum/27072/335522.html
http://www.dykarna.nu/fotoalbum/27072/335571.html

#3 and now temperatures measured at different points in the circuit.

pic (1) shows temps during warm-up

http://www.dykarna.nu/fotoalbum/27072/335573.html

pic (2) shows temps with 100 C at instrument cluster and 99 C at the pipe by the engine with the bleed screw just before the fans come on.

http://www.dykarna.nu/fotoalbum/27072/335574.html

pic (3) shows temps just after fans have cooled everything down again

http://www.dykarna.nu/fotoalbum/27072/335575.html

Looking at these results we are completely confused......temps indicate the coolant is actually going in the opposite direction from what it should?

The car is a S2 111S from 2004 which has the small twin fans and also the radiator bleed screw is on the right hand radiator hose which is also as on the Toyota cars.....and now it seems that the coolant flow is actually reversed?

We are lost.....

[Numbnutz]

S2 111s on my04 has the bleed screw on right pipe at top of rad (difficult to get to) - so you need to park with front right elevated to bleed. (I've got a triple pass rad fitted - that was awkward to bleed ha ha)

 

Twin fans sounds like you have air con fitted? As air con brings the second fan in if AC gas pressure is too high/warm. Do you have AC?

 

Your pics show that you have the water re circulation pump fitted (for ppl that just turn their engine off after a blast, rather than allowing it to cool down with a slow easy last mile or so, I think it comes on around 104-110' with engine off). I trust you have metered this to make sure it's not running when the engine runs. I think it can't run unless your relay is broken.

 

Have you told EP that you have a VVC with my04 re-circulation pump - does the kit definitely fit this set up as recirculating was I think my04 onwards - which was my04/5 only. The recirculating pump pulls water from the outlet pipe and pushes it back to the OEM thermostat, it may also trigger the fans if it's too hot, but doesn't circulate water via the rad.

 

Your diagrams suggest there is a flow problem - I need to have a think why, but I no longer have the same setup.

Your hand drawn pic 1 should be - I think:-

Coolant outlet from the top of engine should be hot during warmup. This goes to a t piece and the lower end goes to the right pipe to radiator, the other t to the new prrt.

The prrt to the pump feeds to the OEM thermostat/pump (metal pipe with. Bleed screw).

The to the rad prrt goes to left hand radiator pipe (as viewed from the rear)

As for the recirculator pipes, I'm not sure if you need to change the flow of these just yet.

It that how it is set up currently?

[Numbnutz]

I did some research and found this http://arc.seloc.org/viewthread.php?tid=344871&page=2#pid5842077

It looks like this guy had your problem and reworked the recirculation pipe work to get it working.

See if his pictures help - looks like you need to call EP - they should know about this.

 

And this post - reckons he got it working without the recirculatiion mods http://forums.seloc.org/viewthread.php?tid=386731&page=1

More discussions here http://forums.seloc.org/viewthread.php?tid=366096&page=1#pid6209200again no mods required ...