Another Heater/Aircon problem

[Catweasel]

My Puma has just developed a problem with only cold air out of the heater/aircon. Ford oem HCV replaced very recently only because the original was 15 years old, the a/c light comes on and the fan operates at all speeds. I have no multimeter to check voltages, etc. Is there a simple way to way to tell if the fault is HCV or Board and which fuses should I check. Thanks for any assistance.

 

[Frank]

[post]348564[/post] Ford oem HCV replaced very recently

...like 'I've still got an airlock' recently?

[post]348564[/post] Is there a simple way to way to tell if the fault is HCV or Board and which fuses should I check

Unplug HCV connector, if HCV then blows hot it's something else. If it still blows cold it could be something else or, err, the HCV which can fail in either the hot/cold position. There is also a hardly known about problem/possibility of the connector pins being ever so slightly too short, so wiggle the connector about.

Personally, I'd put a meter on it all.

If your clock and interior lights work then the fuse on the heater module is OK (Fuse 2, red 10A)

 

[Catweasel]

Thanks Frank.
Presumably no airlock as the system has worked happily for a couple of months since the HCV was replaced, - purely as a precautionary measure.
Will try playing around with the connector as suggested, I think the clock and lights are still working but will re-check tomorrow.

 

[Frank]

[post]348583[/post] Presumably no airlock as the system has worked happily for a couple of months since the HCV was replaced, - purely as a precautionary measure

Yeah, air lock risk would be first few days, a week max, I reckon. What was the condition of your old HCV when you took it out? - I'm asking because I'm planning to do exactly the same precaution change on this as you.

 

[moondustka]

Is it possible for the HCV to to fail in such a way that it won't fully open? I have a problem with mine I think - it will shut so I can get cold air, but I can't get fully hot. Both pipes going to the HCV are hot, but the pipes the other side (heater matrix) are warm-ish. If I have the fan speed on 1 then I can get warm air. If I turn it to 3/4 I get very luke warm.

If the valve is working correctly, maybe I could have an air lock in it?

Also which is he right one to buy? I heard there was a revised one?

Thanks, Ben

 

[Catweasel]

[post]348599[/post]

[post]348583[/post] Presumably no airlock as the system has worked happily for a couple of months since the HCV was replaced, - purely as a precautionary measure

Yeah, air lock risk would be first few days, a week max, I reckon. What was the condition of your old HCV when you took it out? - I'm asking because I'm planning to do exactly the same precaution change on this as you.

The 15 year old original HCV seemed OK but replaced as a precaution since the same age HCV on my son's Puma sheared both stubs facing the engine. The hoses kept everything in place and nothing visible until a cloud of steam and hot water erupted. I replaced with a recently purchased genuine Ford HCV.

Amazingly I have the heating working again after only gently rocking the HCV to make sure the stubs were OK. I guess perhaps an intermittent connector problem.

 

[Frank]

[post]348606[/post] Amazingly I have the heating working again after only gently rocking the HCV to make sure the stubs were OK. I guess perhaps an intermittent connector problem.

Good, that was an easy fix. At your leisure, I reckon spray that connector with proper Contact Cleaner and cotton buds and that should be it. If it does it again, then probably the short pin problem (you're talking 1 - 2 mm short) and it's a 30 minute fix.

[post]348604[/post] Is it possible for the HCV to to fail in such a way that it won't fully open? I have a problem with mine I think - it will shut so I can get cold air, but I can't get fully hot. Both pipes going to the HCV are hot, but the pipes the other side (heater matrix) are warm-ish.

Yep, can fail in any position (variable position plunger/solenoid). I *think* a heater maxtrix air lock would show itself (with heater set to max) by the HCV to matrix +ve flow pipe being damn hot and the -ve return being far cooler. If both, as here, are luke then it suggests not an airlock.

Disconnect connector and HCV should fall back to 'damn hot' position. If it doesn't, then it's that. If it does, then meter on connector and make sure you're showing variable voltage for different heater positions.

[post]348604[/post] Also which is he right one to buy? I heard there was a revised one?

This - http://www.fordpartsuk.com/shop/ford_puma_heater_control_valve_f_1714716_c_585.htm the 2007 (?) improved version. Go by part number and they do them on Amazon and all over the place.

*Top Tip* - for people using old HCVs, carry on of these and a couple of Jubilee clips in your toolkit. If those plastic stubs break off, you're going to be stuffed otherwise.

 

[moondustka]

Thanks for that Frank, will unplug and see what happens. If no change, then I'll order a new one.

 

[Dazzler21]

[post]348575[/post]

[post]348564[/post] Ford oem HCV replaced very recently

...like 'I've still got an airlock' recently?

[post]348564[/post] Is there a simple way to way to tell if the fault is HCV or Board and which fuses should I check

Unplug HCV connector, if HCV then blows hot it's something else. If it still blows cold it could be something else or, err, the HCV which can fail in either the hot/cold position. There is also a hardly known about problem/possibility of the connector pins being ever so slightly too short, so wiggle the connector about.

Personally, I'd put a meter on it all.

If your clock and interior lights work then the fuse on the heater module is OK (Fuse 2, red 10A)

When you say if it still blows hot it's something else, what could something else mean?

 

[tuonokid]

http://www.pumaspeed.co.uk/product-Original-Equipment-Ford-Heater-Control-Valve_499.jsp

Info regarding part nos for HCVs. Note STEAVIE on here sells them for £40 delivered (the latest one)