D.C. landlords are not required to provide or maintain laundry machines, including washers and dryers by the D.C. Housing Code. However, some leases (perhaps in luxury building) may include promises from landlords they will fix them.
If there is no lease or the lease is silent about fixing appliances, furnishings, and laundry services, then the landlord does not have to provide or fix broken washing machines or dryers.
If the lease does promise it, then the landlord must fix it. If the landlord violates the lease, the tenant is free to move out or take the landlord to landlord-tenant court or small claims court to get a court order or perhaps a reduction in rent. Overall, there are not strong protections for tenants if the landlord does not fix a laundry machine in a D.C. apartment.