2018 Mallard M312 water heater

We bought a used M312 in Dec 2021 from a dealer. It had been winterized, but we were led to believe everything had been flushed and set up for use before we picked it up. I have looked through every manual I can find to verify this was true (with minimal success), but I still can't get the water heater to work. There are no valves that I can see in the small heater compartment, and to my knowledge there is no "basement" storage on this model.

My questions: Where are the bypass valves for the water heater on this model and how can I verify that the tank is full before I continue trying to get it working?
Has anyone else experienced a leak over the shower from the sky light?
We are connected to city water and there is plenty of pressure at all outlets, except the outdoor shower where it dribbles out at best. Any suggestions?

Thanks in advance.


Well-known member
First, do not turn on the electric or gas to the water heater until you are sure there is water in it. It will damage the heater.

The bypass should be close to the water heater, you may need to take down the wall in the storage area to get to it. The basement storage is what refer to where the small storage doors are on the outside, near the front.

The skylight leak, the sealant around the top of it will need to be checked, maybe reworked. For this use Dicor self-leveling sealant. You can also use Eternabond tape: