2007 Ford Focus2 1.6 petrol - Slow heater warm up

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Mon 15 Dec 2014 15:06
2007 Ford Focus2 1.6 petrol - Slow heater warm up - Pete Mansell

The interior heater on this car always used to warm up very quickly. For some time now, although the engine temperature gauge shows that the engine heats up very quickly, the heater can take about 15 minutes to get hot enough. There is then plenty of heat.

Therer are no coolant leaks, the engine runs fine and no work has been done on the coolant system.

Does anyone have any idea what may be the cause? I was wondering if there could be an air lock somewhere, but if that were the case would the heater eventually start working properly?

Many thanks.

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Mon 15 Dec 2014 19:49
2007 Ford Focus2 1.6 petrol - Slow heater warm up - Quicksilver

Is the thermostat OK, (stuck open?)? Water circulating OK, (water pump pumping?)?.

What is the temperture on the radiator top hose and what is the bottom hose temperature.

I think it will be the thermostat as otherwise it would overheat.

Q.

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Mon 15 Dec 2014 22:30
2007 Ford Focus2 1.6 petrol - Slow heater warm up - Peter.N.

Are you saying that the temperature guage shows normal temperature quite quickly? If so its unlikely to be the thermostat although I wouldn't rule it out as the temperature sensor could be faulty.

Check the temperature of the top hose from start up, it should remain cold or almost until the gauge reaches normal temperature, then it should suddenly get hot as the thermostat opens. If its doing this then you could have an airlock in the heater circuit unless this car uses an electrical valve to control the temperature like the Fiesta in which case that could be faulty.

Edited by Peter.N. on 15/12/2014 at 22:31

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Mon 15 Dec 2014 23:27
2007 Ford Focus2 1.6 petrol - Slow heater warm up - Pete Mansell

Many thanks for those suggestions. Yes, the temperature gauge seems to quickly show the normal engine temperature. Tomorrow I will start the engine and monitor the top hose as suggested.

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Wed 17 Dec 2014 09:37
2007 Ford Focus2 1.6 petrol - Slow heater warm up - Pete Mansell

Following the above suggestions, I have started the engine and monitored the radiator hoses. The hoses remain cool until the temperature on the guage starts to climb above about 70 deg c, after about 10 minutes ticking over. The gauge then quickly climbs to 90 degrees, where it stays for most of the time, for all kinds of driving.

To me this seems to rule out the thermostat.

I've just tried the heater and after this 10 minutes ticking over, the heater is starting to get warm. However, if I drive straight off with a cold engine, the guage quickly gets to 90 degrees, and then it's another 10 minutes until any real heat comes from the heater.

Wierd. I don't understand what is going on!

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Wed 17 Dec 2014 09:46
2007 Ford Focus2 1.6 petrol - Slow heater warm up - skidpan

Don't forget that the gauge in all modern cars is little better than a warning light because it is not linear. It will go fairly quickly to normal but if you check the temp using a propper gauge it will probably be no hotter than 60 degrees at this point. Then it will stay at normal even when the fans are running, they don't turn on until 110 degrees in most cases. Then when the engine gets to probably 120 or more the needle will instantly jump into the red giving you no warning at all.

In the past I have used a digital volt meter with a simple thermocouple to check temps and water flow. They are available on e-bay and at Maplins. Cost probably £15 but are well worth it. Simply stick the end of the thermocouple to a metal surface (don't stick it to rubber or plastic since they are poor heat conductors and will give a false reading) and you can watch the temp rise.

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Wed 17 Dec 2014 12:33
2007 Ford Focus2 1.6 petrol - Slow heater warm up - Peter.N.

Sounds from that you have a water flow problem, could be an airlock or a blocked matrix, unless as I mentioned it has an electric water control valve, I think you will find this on the flow pipe thtough the bulkhead in the engine compartment.

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