Bosch Dryer DR Error — Usually the Sump, Not the Pump

A DR error on a Bosch ventless dryer usually means the machine thinks it cannot drain condensate. On this WTG865H3UC/02 the pump was working perfectly — wet lint had built up around the water-level sensing contacts and kept them bridged. Cleaning the sump cleared it. Total was $220, no parts.

Job details

Model: Bosch WTG865H3UC/02, 800 Series ventless condensation dryer
Symptom: DR error, cycle would not finish
Suspected: Failed condensate pump
Actual cause: Lint sludge bridging the water-level sensing contacts
Fix: Cleaned sump, pump assembly and sensing area
Cost: $220
Location: West Hollywood, CA

How a ventless dryer handles water

This is worth understanding, because it explains why the failure happens at all.

A vented dryer pushes hot moist air out through a duct. A ventless condensation dryer does not. It cools that air, condenses the moisture into liquid water, collects it in a sump at the bottom of the machine, and a small condensate pump moves it to the drain or a reservoir.

No duct means nothing leaves the machine. Lint that gets past the filters stays inside, settles in the sump, and mixes with condensate. Over months it becomes wet sludge.

Why the DR error is misleading

DR points at drainage, so the pump is the obvious suspect. On this unit the pump ran fine when tested directly.

The actual fault was the water-level sensing contacts sitting in the sump. When condensate rises, the water bridges those contacts and the control board starts the pump. When the water is gone, the circuit opens and the pump stops.

Wet lint had packed around the contacts and was bridging them permanently. The board kept reading water that was no longer there, ran the pump, saw the level never clear, and threw DR — a drainage fault on a machine that was draining normally.

The repair

I opened the lower condensate area, removed the sump and pump assembly, and cleaned everything out — the sump, the pump housing, and the sensing contacts. Reassembled and ran a full cycle. No error, and drainage behaved normally.

No parts were needed. On a call like this the cost is labor and access, not components.

What it cost

$220 total. A condensate pump replacement on this model would have run higher, and it would not have fixed anything — the pump was never the problem.

Frequently asked questions

What does the DR error mean on a Bosch dryer?

It indicates a drainage problem in the condensate system. That can be a failed pump, a blocked drain hose, or — as in this case — sensing contacts that are bridged by debris and report water that is not there.

Do ventless dryers need maintenance a vented dryer does not?

Yes. In a vented dryer, lint that gets past the filter leaves through the duct. In a ventless machine it has nowhere to go and accumulates in the condensate area. The sump needs cleaning periodically, and most owners never know that.

Can I clean the sump myself?

The filters and the condenser unit are user-serviceable on most models and worth cleaning regularly. The sump and sensing contacts sit deeper and require partial disassembly, which is where a service call makes sense.

Will the error come back?

Not if the sump was cleaned properly. It will return over years as lint accumulates again, which is why periodic cleaning matters on ventless machines.

Bosch dryer error in West Hollywood?

Vertex Appliance Repair works on Bosch, Miele, LG, Samsung, Whirlpool and other dryers in West Hollywood and nearby Los Angeles neighborhoods. The $89 diagnostic is waived when you approve the repair, and completed work carries a 90-day warranty on parts and labor. See dryer repair in West Hollywood or call 323-747-7098.