21 replies to this topic

[madalicesdad]

The manifold heater is not a peltier device.
PTC is positive temperature coefficient which means the hotter it gets (either by it's own heating or the heat of the engine coolant) the less current it draws. The material itself thus limits how hot it gets and when hot, it effectively turns itself off.
A peltier device transfers heat from one side to the other and needs to have the heat removed from it. It will burn itself out if just connected without anything to lose the heat, and a small spray of fuel may not be enough.
Note this comes from my experience building a beer fridge using peltier cooling, but if it can burn skin, it may not be wise to spray fuel on it

[genpop]

@madlicesdad

 

Manifold heater (SPi)
The ECM controls the manifold heater
through a relay. This heater works on the PTC
principle, and allows a greater current to
quickly heat the inlet manifold during the warmup period.
This allows better driveability during
engine warm-up. Once a preset temperature of
approximately 75° C is reached, the ECM tums
off the relay. If the ignition is switched to the
'on' position and the engine is not cranked, the
ECM will turn off the manifold heater after a few
seconds. The manifold heater will also be
turned off to prevent battery overload during engine cranking.

[Ethel]

Could this be closer to the original?

 

No idea about the dimensions, power....

[madalicesdad]

@madlicesdad

Manifold heater (SPi)
The ECM controls the manifold heater
through a relay. This heater works on the PTC
principle, and allows a greater current to
quickly heat the inlet manifold during the warmup period.
This allows better driveability during
engine warm-up. Once a preset temperature of
approximately 75° C is reached, the ECM tums
off the relay. If the ignition is switched to the
'on' position and the engine is not cranked, the
ECM will turn off the manifold heater after a few
seconds. The manifold heater will also be
turned off to prevent battery overload during engine cranking.

So give it a go then 🤷‍♂️
Doesn't change the fact that an inadequately cooled peltier device will get 'kin hot and spraying fuel on something hot enough to burn skin might not be a sensible idea.
A PTC device is self limiting even without the ECU control. Peltier devices are not

Edited by madalicesdad, 24 December 2023 - 05:13 PM.

[genpop]

You may be right but I have never heart that those modified engines started to burn!

[genpop]

@ the admins

 

may one of you rename this thread?

 

There is no " temperature pressure compensator" on the mini!

Edited by Ethel, 05 January 2024 - 12:48 PM.
Title provisionally edited - other topics also use the term TPC

[R32Egor]

Hi all,

 

I know this is an 'old' post, but I'm looking at buying a 96 spi that has no temp gauge reading and seems to lack power/not a spritely as it should be.

 

I've been told this is likely to be a cause/one of the causes.

 

If so - is this https://www.ebay.co....QsAAOSwjy1fOXbj the 'peltier' element - and is it a case of fitting as per the description above?

 

TIA

The answer to your question would be a no the PTC would not have any effect on your description.

The only thing it might effect is a little sluggish when cold before the engine is warm and then it would run fine.