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SOP with heat exchanger for WINTER operation

SOP with heat exchanger for WINTER operation

I asked the spray guys 'why is your pump laboring really hard, we don't know! ' So I felt around on the hoses next to the heat exchanger and discovered that the heat exchanger was Hot but disconnected to the pump, no membrane was going through it. The hot water was just circulating from the truck radiator to the heat exchanger and back. When we asked the mechanic why it was disconnect, he said that the heat exchanger was always getting clogged up so he disconnected it. That solved the problem! The guys in the field had no idea that it was disconnected, they only knew the product was coming out rough and not the same as in the summer. They didn't understand how the equipment works and why. This scenario is more frequent than I wish were the case and this is the reason for this winter technique.

The reason the mechanic disconnected the heat exchanger was not because he wanted to make their job harder but because the spray guys didn't understand how to work or operate the heat exchanger without messing it up or clogging it up, so he was tired to fixing so he just disconnected it.

Action point: Heat exchangers MUST be turned OFF after spraying EVERYTIME! Why? Because the hot water 'cooks the water out of the asphalt' and clogs it up.
I asked waterproofing manager if I created a SOP(standard operation procedure)would he placard it to the wall of the spray truck, he said yes, so I did. I have included it for you to use, modify it to make it apply to your unit.

SOP (Standard Operating Procedure) for winter Operation using Heat Exchanger Check Lists

Pre- Spray procedure

1) Truck Engine running the entire time on job
2) Start engine/pump idle speed(spray unit)
3) Move pump control valve to ON position(begins asphalt flow) (see # 3)
4) Heat Exchanger- Move valve into ON Position (see #4)
5) Recirculate material during wall prep
6) Shut down pump unit to relieve pressure to hose
7) Disconnect hose from tank-insert to gun
8) Start pump/engine unit
9) Spray Foundation

Post- spray procedure

1) Turn off pump/engine
2) Move pump control valve to OFF position (#3)
3) Move Heat Exchanger to OFF position(#4)
4) Re-Connect hose to tank –gun in bucket
5) Secure contents for travel
Caution: failure to shut off the heat exchanger prior to travel will cause blockage and permanent damage to the unit.