Tenant in nice property not paying utilities

[Tanya F.]

We had new tenants move in this past April into an A/B property and we learned they haven't been paying the gas bill.  Their credit was 675 and income was good and all references checked out as excellent.  We include the electric and water utility in the rent, but the tenants pay the gas. We've done it this way for many previous lease terms, but we may change that after this experience.

They made no gas payments since moving in. In the summer, the only gas used is for the hot water heater, and the water going to the hot water heater is preheated by solar. So the summer gas bill is tiny in terms of therms of gas used, but there's a ~$20 fixed distribution charge, which is pretty standard as far as I can tell. So (maybe because they are rebels?)  they decided not to pay, and the gas was shut off two weeks ago. The house is plumbed strangely so one of the two water heaters is shared, so other tenants had no hot water (there were a series of cloudy days).   Those other tenants pay the gas for the shared clothes dryer. 

So the bill should be in our name.  We don't want to get into a battle. We're looking for help here in drafting a letter to them to say how unacceptable this is.  Who knows what other bills they aren't paying.   They need to be told this is serious. This unit is being rented under market rate. So we can raise the rent next spring for sure.

After you have accepted tenants, do you ever re-screen them before renewing? I'm sure their credit rating has tanked after not paying gas since April. They are also supposed to share duties mowing the lawn, and have been slackers in that regard, according to the other tenants.

So, any ideas for wording our letter?