Drain fault on Hoover VT 816 D22X/1-80

[mace]

Hi folks,

The background:

I picked this machine up for free, sold as having a

‘drain’ fault.
The cover was off, so someone had already been in the machine previously.

Pump has been tested and confirmed as working fine.

Filter and all pipes disassembled and are clean. Pressure switch pipe
is clear, as is the air reservoir in the drum (checked with a camera).

Machine runs through a cycle, and gets to the point where it wants to
drain. It empties fine, but I believe the machine is not detecting that
the drum is empty due to the pressure switch.

I ordered a pressure switch for a Hoover VT 816 D22X/1-80.

Switch arrived and looks identical to the one removed from the machine.

It has four terminals, as the existing one did, but there are
only three terminals in the wiring loom for the machine, and the plug
is keyed such that it will only fit on terminals 16 (red), 11 and 14
(both blue).

Fault persisted after fitting the new switch.

I disassembled the old switch to check the internal connections, and
discovered that:

11 is connected to 12 if drum is empty
11 is connected to 14 if water level is high enough
11 is also connected to 16 if water level is excessively high

The problem with this, is that the harness on this machine is keyed
such that 12 is not connected on this pressure switch, so it can never
detect an empty drum.

Any thoughts? Is there another switch for this specific model?

Thanks.

[electrofix]

well my thought are have you got the correct switch for machine

if you post the long number inside the door and the part number of the switch you have someone who has hoover access may be good enough to check

if you are getting continuity through the old sw then it must be ok

have you checked wiring loom for pressure sw back to the board and checked for blockages in the pressure hose

Dave

[iadom]

Have you checked the wash heating element for low insulation. 😉

[mace]

iadom wrote:Have you checked the wash heating element for low insulation. 😉

I’ve done a resistance test on it and it looked OK. No measurable leakage to ground. Didn’t do a high voltage test, as I don’t have the gear for that.

[mace]

electrofix wrote:well my thought are have you got the correct switch for machine

if you post the long number inside the door and the part number of the switch you have someone who has hoover access may be good enough to check

if you are getting continuity through the old sw then it must be ok

have you checked wiring loom for pressure sw back to the board and checked for blockages in the pressure hose

Dave

Hi Dave,

Machine number is 3100582713430523.

Label on old switch reads:
MADE in P.R.C -385/13-A02 37650126
41035075 70/50 -340

Replacement switch from UKWhitegoods has the following etched on to it:
0241/18-37650125-01
41035075-70/50-340

Both also have “Type 760” moulded on the back.

I’ve checked thoroughly (including using an endoscope in the drum) for blockages in the pressure hose. It’s definitely OK.

I’ve not electrically checked the wiring loom back to the board yet, but visually it’s in good order.

My concern was more that the three wire connector doesn’t use terminal 12 at all, and as best I can tell visually, that’s the only terminal that could be used to determine that the drum is empty. Unless they are using the absence of voltage on 14 and 16 as an indication, which is a bit “how you’re doing” 🙂

I’ll check the loom out later, and confirm it’s OK.

Ta!

[electrofix]

yes the absence of a connection can be used to determine its drained. it works ok as long as there are no electrical leaks in the system that fool the board into thinking its still full

Dave

[iadom]

mace wrote:

. No measurable leakage to ground. Didn’t do a high voltage test, as I don’t have the gear for that.

It is the only way to show up a faulty heating element, it is a known cause of ‘apparent’ drain faults on Hoover machines.

[electrofix]

iadom wrote:

It is the only way to show up a faulty heating element, it is a known cause of ‘apparent’ drain faults on Hoover machines.

will that machine run with heater disconnected as a test ?

Dave

[iadom]

Not certain, may throw up a different error code, perhaps running on rinse cycle it may do.

[mace]

I’ve checked the wiring harness and confirmed continuity.

As you mentioned heater element, I’ve just refilled the drum and checked the resistance on the heater element – I’m getting 41 Ohms. I thought it was somewhat lower when I checked the other day, but I could be mistaken. Will need to let it dry out to see if that changes.

I’ll refill it and run a drain cycle, see if it errors out on that. Will leave the heater element disconnected during that cycle.

[mace]

Manually filled drum, then ran a drain cycle, with heater element disconnected. Completed without error.
Will now run a 30 minute cycle, with heater element disconnected and ‘cold wash’ selected, and see how that gets on.

[mace]

Ok, 30 minute cold cycle completed without error. Also ran a full speed spin cycle afterwards which also completed fine.

[iadom]

Heater resistance is not important, it is the insulation that is the cause of this problem. Testing with a meggar at 500v is what is needed, a basic multimeter is not enough. Your testing does point to a faulty heater though. 🙂

[iadom]

With regard to the third connection on the pressure switch, it is used to trigger the overfill circuit. I did suspect this but couldn’t access the tech info yesterday. It doesn’t register a click when you blow into the switch though.

[mace]

iadom wrote:Heater resistance is not important, it is the insulation that is the cause of this problem. Testing with a meggar at 500v is what is needed, a basic multimeter is not enough. Your testing does point to a faulty heater though. 🙂

Nod – if I could justify a megger, I’d have one 🙂
Have ordered a heater element and will see how that gets on, ta.

[Author]

Posts