Washer Fluid and Methanol Soap

[MEP001]

Just for fun, I created a purge program:



I1 is a bay input, I2 is weep high, I3 is weep low. I added both for versatility of connection - if I3 is used, I2 would simply be hard-wired.

If I1 (Foam brush for a particular bay) is triggered for more than 2 seconds, the purge is activated but not started (Block B005). Once the foam brush has been OFF for a determinate time (I used 5 seconds just because) the purge starts (Block B001). You can see the connections at B001 to both the first and second input - the top is the trigger which is inverted (This particular block starts its sequence with a signal low condition), the other will cancel the timer, so if the foam brush is turned back on the purge will stop. Q1 is the output, B002 is an "AND" relay, meaning that all wired inputs must be active for the purge to work. You can see I2 hot from being switched on, I3's connection hot from the input inverted, so once the purge signal reaches its terminal it triggers B002 and ultimately Q1.

 

[Jeff_L]

MEP, can you explain to me "weep high" and "weep low"?

 

[MEP001]

MEP, can you explain to me "weep high" and "weep low"?

It's the input to turn on the purge. Some use a normally open weep solenoid and have power to the coil when it's above freezing to keep it closed, some have a normally closed and send power when it drops below freezing, so I set it up to accept either.

I just realized that I didn't put anything in place to purge when the weep comes on, but that would be a very simple fix.

 

[Ric]

Weeping water thru a foam brush is not very popular in the northern states. The water freezes the bristles. A purging of windshield washer fluid would eliminate the weep all together.

 

[MEP001]

Weeping water thru a foam brush is not very popular in the northern states. The water freezes the bristles. A purging of windshield washer fluid would eliminate the weep all together.

That's exactly what we've been discussing, an antifreeze purge.

 

[RykoPro]

Here is a actual schematic I drew up in Word. The power supply for the timers can be from 5VDC to 240VAC without any changes other than the supply. This only shows one bay.

 

[RykoPro]

Here is the supply circuit showing the timers hooked up in parrallel.

 

[RykoPro]

There are other options that could be added like air control to the pump in case of leaks on the output side of the air pump or even an "air before fluid purge".

 

[washtubman]

I'm a bit confused (not the first time). If you are using methanol FB, then why do you purge the lines?

 

[MEP001]

One of the ideas was to use methanol foam brush soap only for the purge.

 

[Bubbles Galore]

I can get one 55 gallon drum of methanol FB soap that will last me all winter versus having to buy 3/55 gallon drums to supply my regular FB soap needs in the winter. It was purely a cost thing for me to want to do this and thus far it is working out great.

Ric: Thanks for the info about Rowley's. It seems that they supply the same chemical brand I use, but for much lower prices.