Hi and welcome. There seems to be a range of products in the Whale Wastmaster series. But if it’s a DC pump and you wire it in reverse then it will simply turn backwards and will not pump.
look more closely, you may see an + and - on the body.
Hi
My name is Hayley and I work in the marketing team at Whale.
Please feel free to contact our Customer Service Team who will do all they can to assist you with your query. You can call them on 0345 9090 911 or email info@whalepumps.com.
Alternatively, please privately send me the best number to get you on and I will get one of our team to give you a call.
Best wishes,
Hayley