That's what I've been doing with all mine, once all my site Prep burning is over I drain them and run some antifreeze through them. Of coarse they don't sit but a month or so and then I've got them back out for understory burning but haven't had any pumps freeze up yet. What electric pump you using for burning? I've been using airtek fuel pumps of both my power torches for the last 4 years and haven't changed them yet, I've been very pleased with them.