The RIMS heater is made from stock 304 SS 1 1/2" pipe fittings ordered from McMaster-Carr. The main body is a 12" nipple with a tee at each end. The right hand tee has a 1" bushing for the heater element and a 1/2" bushing for the outlet plumbing. The left end has a plug and a 1/2" bushing for the inlet plumbing.
Why a tee and not an elbow on the inlet end? The heater needs to be thoroughly cleaned on a regular basis. The plug makes it easier to get a clear shot through the heater tube with a brush.
The thermocouple is an Omega CF-000-J-2-60-1 mounted in a fitting I made from 1/2" copper pipe, two male sweat adapters, and an 1/8" brass pipe nipple filed down to fit the curvature of the pipe.
Heating is provided by a 230 volt, 4500 low watt density stainless steel hot water heater element obtained from one of the local home supply stores. It is operating on 115 VAC supplied through a 10 amp solid state relay (SSR) in the controller and provides approximately 1000 watts.
The red-handled valve on the left is used to dump liquid from the heater and the blue-handled valve on the right controls the output flow the the mash tun return manifold.
The protective cap over the heater wiring was made from a 2" PVC coupling, a 2" elbow, a 2" to 3/4" reducing bushing (a standard 3/4" electrical cable clamp can be force threaded into the bushing), and a large hose clamp. One end of the coupling had to be enlarged to fit over the end of the stainless steel tee. I clamped the coupling (a difficult task) in my drill press vice and drilled one end very slowly with a 2" hole saw to a depth of about 1/2". The drilled end was then slotted with a hacksaw to allow it to compress when the hose clamp is tightened.