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paulgato · 03-08-2014, 04:42 PM

Next, under-the-bonnet views...

The front junction box is loosely tucked in between the headlight and the washer reservoir. It doesn't move about and it's of lightweight plastic construction with rounded corners so it won't damage anything. The cables in that viscinity are not clipped to anything so the box can be lifted well clear for access.

I used waterproof (IP67) electrical junction boxes and cable glands. They were quite cheap. As a temporary measure, I fitted an ON/OFF rocker switch to the side of the rear junction box above the pre-heater. This means I have to go out an hour before driving off and lift the bonnet to switch on the pre-heater. That's not really hard work, but I do intend to replace that switch with a remote switching device that comes with a key-fob actuator, so I can switch the pre-heater on from inside the house. That rear junction box MAY be JUST big enough to accomodate the remote switching unit, but I'll probably have to find a slightly larger one.

The rear junction box is attached to an existing bracket on the bulkhead/firewall, as is the support bracket for the heater itself. (And yes, I made that support bracket from a length of 22mm copper pipe, beaten flat, bent and drilled! It works well!) The pump is light and is supported solely by the hoses themselves. The pump is a 12v one and came with a little mains adapter, which is tucked in behind, below and to the right of the rear junction box. There is a green/yellow mains earth connection between the pre-heater can and a ring connector bolted to the bracket on the firewall.

One would normally fit the pump and pre-heater can on the return from the car's heater matrix, but the layout of the hoses would not permit that as the return stub on the engine was pointing upwards, which would have resulted in a 'high loop' of hose, where an airlock could potentially have formed. Consequently, the pump and pre-heater are on the flow hose to the heater matrix, and everything runs smoothly uphill away from the pre-heater can, both back through the pump to the engine and forwards on to the matrix. Hopefully this will ensure that air is always going to be released out of the pre-heater can.

The pre-heater can is angled slightly backwards so the inlet and outlet hose connectors are pointing slightly upwards away from the pre-heater. (A 2kw heater element will burn out pretty quickly if exposed to air! The main thing you can get wrong when installing a coolant heater is to allow an airlock or a vapour lock to occur. This was one reason for choosing the 2kw model instead of the more usual 3kw model: to allow a bit more margin for error!)

Getting that heater can and pump fitted correctly was by far the hardest part of this installation. It took me a full day and a fair bit of trial and error before I had it securely fitted where the pipes and hoses ran correctly and nothing was interfering with anything else back there. (No cables, hoses or anything else at risk of chafing or overheating on anything.)

By the way the pre-heater is made by a UK company called Kenlowe. Very helpful people. Not cheap though. Their web site is truly awful, way out of date, and only shows their older heaters. But for what it's worth, here's the URL...

KENLOWE

As you can see, the battery charger is tucked in beside the washer reservoir and cable-tied in position. The charger is a CTEK MXS 10. It has no fan and is waterproof to IP65 standard, so I am not worried about it getting splashed when I'm filling the reservoir. Likewise with the junction box - that's totally waterproof. The charger has a specific AGM setting, and a remote temperature sensor, so alters its voltage according to the temperature in the viscinity of the battery. Without the temperature compensation there would be a risk that the battery could be undercharged in winter, and worse, that it could be drastically overcharged in the summer if the sun is beating down on the bonnet.

[Oh, ha ha - in this first photo you can just see the little red bullet connector behind the alternator, which is where I disconnect/reconnect my alternator field wire. Eventually I will run a pair of wires from these connectors to a switch on the dash.]

03-08-2014, 04:42 PM	#42 (permalink)
paulgato EcoModding Apprentice Join Date: Sep 2013 Location: Oxford, UK Posts: 126 Black Beast - '02 VW Goff Estate S Thanks: 27 Thanked 51 Times in 31 Posts	Even more photos... Next, under-the-bonnet views... The front junction box is loosely tucked in between the headlight and the washer reservoir. It doesn't move about and it's of lightweight plastic construction with rounded corners so it won't damage anything. The cables in that viscinity are not clipped to anything so the box can be lifted well clear for access. I used waterproof (IP67) electrical junction boxes and cable glands. They were quite cheap. As a temporary measure, I fitted an ON/OFF rocker switch to the side of the rear junction box above the pre-heater. This means I have to go out an hour before driving off and lift the bonnet to switch on the pre-heater. That's not really hard work, but I do intend to replace that switch with a remote switching device that comes with a key-fob actuator, so I can switch the pre-heater on from inside the house. That rear junction box MAY be JUST big enough to accomodate the remote switching unit, but I'll probably have to find a slightly larger one. The rear junction box is attached to an existing bracket on the bulkhead/firewall, as is the support bracket for the heater itself. (And yes, I made that support bracket from a length of 22mm copper pipe, beaten flat, bent and drilled! It works well!) The pump is light and is supported solely by the hoses themselves. The pump is a 12v one and came with a little mains adapter, which is tucked in behind, below and to the right of the rear junction box. There is a green/yellow mains earth connection between the pre-heater can and a ring connector bolted to the bracket on the firewall. One would normally fit the pump and pre-heater can on the return from the car's heater matrix, but the layout of the hoses would not permit that as the return stub on the engine was pointing upwards, which would have resulted in a 'high loop' of hose, where an airlock could potentially have formed. Consequently, the pump and pre-heater are on the flow hose to the heater matrix, and everything runs smoothly uphill away from the pre-heater can, both back through the pump to the engine and forwards on to the matrix. Hopefully this will ensure that air is always going to be released out of the pre-heater can. The pre-heater can is angled slightly backwards so the inlet and outlet hose connectors are pointing slightly upwards away from the pre-heater. (A 2kw heater element will burn out pretty quickly if exposed to air! The main thing you can get wrong when installing a coolant heater is to allow an airlock or a vapour lock to occur. This was one reason for choosing the 2kw model instead of the more usual 3kw model: to allow a bit more margin for error!) Getting that heater can and pump fitted correctly was by far the hardest part of this installation. It took me a full day and a fair bit of trial and error before I had it securely fitted where the pipes and hoses ran correctly and nothing was interfering with anything else back there. (No cables, hoses or anything else at risk of chafing or overheating on anything.) By the way the pre-heater is made by a UK company called Kenlowe. Very helpful people. Not cheap though. Their web site is truly awful, way out of date, and only shows their older heaters. But for what it's worth, here's the URL... KENLOWE As you can see, the battery charger is tucked in beside the washer reservoir and cable-tied in position. The charger is a CTEK MXS 10. It has no fan and is waterproof to IP65 standard, so I am not worried about it getting splashed when I'm filling the reservoir. Likewise with the junction box - that's totally waterproof. The charger has a specific AGM setting, and a remote temperature sensor, so alters its voltage according to the temperature in the viscinity of the battery. Without the temperature compensation there would be a risk that the battery could be undercharged in winter, and worse, that it could be drastically overcharged in the summer if the sun is beating down on the bonnet. [Oh, ha ha - in this first photo you can just see the little red bullet connector behind the alternator, which is where I disconnect/reconnect my alternator field wire. Eventually I will run a pair of wires from these connectors to a switch on the dash.] Last edited by paulgato; 03-08-2014 at 06:10 PM..