Recommendation of Ultra Quiet Contractor - Underfloor Heating

[Lucio de Godoy]

Hi All;

I have a flat with 6 areas warmed via underfloor heating. Each of the areas are controlled by its own thermostat Microline Ultra-Thin Thermostat with display, and there are 2 models used:

2 x OTN2-1991 with floor sensor (bathroom)
4 x OTN2-1999 with built-in room sensor (other rooms)

Microline Manual Link:

Power is applied on Microline terminals 1 and 2, via the setup explained below.

These 6 individual areas are combined into 3 major areas. These major areas are controlled via its own contactor HAGER ES 200 (25A/230V) controlled by a Drayton Timer.

Because of the "clank" noise when contactors are switched-on/off and the humming noise when on, I decided to replace this mechanical system with a Solid State Contactor (Croydon CRKA2430).

Great!! the clank and humming noise are gone!! However due to the way the Solid State Contactor operates, I noticed that there is a voltage leakage of about 16VAC, enough to mess-up the programming on the Microline Thermostat.

Not sure how to resolve the voltage leak, but my question is: Do you know of any 25A Ultra Quiet contactor, that will not make a huge clank and humming noise pls?

Many thanks

Lucio

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[Hellmooth]

I had the same issue a while back, managed to get one that was pretty silent and reasonably priced, took a few attempts though! You also need to make sure the contactor is the correct type for heating, some are only for lighting or similar loads. I will check back my invoices for the make.

 

[westward10]

I assume all those block connectors are temporary.

 

[Lucio de Godoy]

@Hellmooth - can't wait, thanks

@westward - there are two sets of blocks, earth cables, and neutral. The earth blocks were there b4, the neutral ones, i've used to connect the N from the heating with the N from mains.

 

[LeeH]

Few quids worth of SSRs there!

 

[westward10]

@Hellmooth - can't wait, thanks

@westward - there are two sets of blocks, earth cables, and neutral. The earth blocks were there b4, the neutral ones, i've used to connect the N from the heating with the N from mains.

I was asking if it was a temporary measure that's all as it doesn't look very professional same as identifying all those greys and blacks

 

[LeeH]

I'd get some klippon terminals in there. You could secure the relays in place with 2 earth terms.

 

[davesparks]

What exactly is the problem with the SSRs?
It is possible that the addition of a few simple components might solve the problem of unwanted/stray voltages.

 

[HandySparks]

... However due to the way the Solid State Contactor operates, I noticed that there is a voltage leakage of about 16VAC, enough to mess-up the programming on the Microline Thermostat.

What exactly is the problem with the SSRs?
It is possible that the addition of a few simple components might solve the problem of unwanted/stray voltages.

Where exactly is this 'voltage leakage'? If it's through the load side of the SSR why should this have any effect on the thermostat?

 

[Lucio de Godoy]

Where exactly is this 'voltage leakage'? If it's through the load side of the SSR why should this have any effect on the thermostat?

Hi, not sure also, but whats happening the thermostat enters into error mode and does not operate next time the power is on.

After some research i found a mechanical replacement: A9C20532 | Acti 9 iCT Contactor, 25 A, 1.3 W, 220 V ac Coil | Schneider Electric - http://uk.rs-online.com/web/p/contactors/7912922/

The other way to look at this is to sound proof the contactor box, is this possible?

I'm still waiting for Hellmooth recommendation.

Thanks

 

[LeeH]

Might get a bit warm!

 

[HandySparks]

Hi, not sure also, ...

What I meant was, between which two points are you measuring this 16V AC?