Rf cylinder stat? Has anyone used one are they good?

I have a job at a b&b that the water is apparently getting scalding. It has an old oil boiler and the hot water is on gravity. I've been out before and the cylinder has been changed not too long ago and has not been installed brilliantly.

My only thought is to convert it to fully pumped but getting a wire back from the cylinder could prove an absolute nightmare. So quick Google and I've found a few rf cylinder stats has anyone used one before? Are they any good?

This also may not work as I can't remember where the cold feed and vent go into the system so I may not be able to convert it if the feed and vent go into the f&r for the cylinder.

One of these maybe an idea for gravity just make sure there's a heat sink rad

Danfoss | 540188 | White

I have used this thermostat a couple of times obviously wired is better but it does do the job and seems pretty accurate

Steve weightman said:

One of these maybe an idea for gravity just make sure there's a heat sink rad

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I dont think there is a heat leak rad but not 100% sure.

Got to love woseley prices.

Riley said:

Danfoss | 540188 | White

I have used this thermostat a couple of times obviously wired is better but it does do the job and seems pretty accurate

Click to expand...

That's the one I was looking at. Will now just have to see where the feed and vent go as i dont really want to pressurise a 30 year old system in a b&b when it's coming up summer.

Steve weightman said:

One of these maybe an idea for gravity just make sure there's a heat sink rad

View attachment 38551

Click to expand...

Hello Steve weightman,

The Danfoss Hot Water Cylinder Thermostatic Valve might be a good suggestion for the OP`s requirements if as He mentions there is an additional `Heat Sink` Radiator and the Feed & Vent pipework on the system will allow or could be altered to suit fitting it.

But - what a price for something that is not much more complicated or expensive to manufacture than a 22mm TRV with a remote sensor probe !

That is an example of a product where the fact that it negates the requirement for a Hot Water Cylinder Zone Valve and the associated Electrical wiring / Electrical thermostat allows the price to be vastly inflated well over the cost of manufacture / manufacturers profit and suppliers overheads / profit.

I know that the Danfoss valve can be bought for less money but still usually way over £120.00.

Obviously in situations such as the OP describes these prices might still be actually be cost effective / easily justifiable compared to other alternatives.

Having written that - a RF Cylinder Thermostat can cost quite a lot more than that and would still require that a Zone Valve was installed for the Cylinder which would have to be wired up - but possibly close to the Boiler ?

Chris