top of page


(a division of Watson Diesel Inc.)

The WD Hot Block was invented as a fix for the ongoing problems that face water haulers and septic tank operators during cold weather operations. Without a means of heating the discharge / inlet valve in freezing conditions, operation of the valve becomes difficult to impossible due to the water in the valve freezing the valve shut.


Up until now the only option was to install a water heated jacket system that uses the trucks engine cooling system coolant plumbed to the valve, or heat the valve manually with an external means such as an open flame torch etc.


The water heated option is a viable option on a “bob tail” truck but this is not an option for the tractor trailer application as running coolant hoses the length of a 40ft trailer is not operationally feasible.

In our opinion the water heating option is not an attractive option from the stand point of cost and the added liability of long runs of coolant going from the trucks engine approximately 30 feet causing the chance of a failed hose or fitting leaking engine coolant.


The open flame option for thawing speaks for itself as open flames, gas wells and residual chemicals in the tank do not mix well together!

The WD family of valve heaters can be installed at a fraction of the cost of water heating and can be installed in approximately 2 hours as opposed to up to 10 hrs to plumb a water heated system.

Visit for more info!

bottom of page