HONEYWELL DT90E Wiring Advice.

[FALLGUY]

Hi one and all,
I have a Worcester Bosch 28CDi Compact Combi Boiler, which was newly installed 2 months ago.
It replaced my old Alpha CB33HE Boiler. I had a Honeywell ST6100A Timer, which I replaced with
a Honeywell ST9100A Timer, just to update the system. I have a Danfoss RMT230 mechanical Thermostat
which I want to replace with a Honeywell DT90E thermostat. I would like some advice on the wiring connections.
The wiring on the old RMT230 is as follows:- No.4-not connected
No.5-not connected
No.1-BROWN Wire
No.3-not connected
No.2-BLACK Wire with Brown sleeving on.
There are a Black wire and a Earth wire with their ends cut off, tucked away not connected.
Would I be correct in saying, the wiring for the new DT90E would be as follows:- BROWN from old stat (No.1)to A on new stat, and BLACK with Brown sleeving from old stat (No.2) to B on new stat?
Any advice would be greatly appreciated! And many thanks in advance!
PS. This is my very first posting as a newby to the Forum! Thanks again, FALLGUY.

 

[oil gasman]

hi
hope u don't mind me saying but it may be a good idea to get a qualified engineer in to have a look for u as it can invalidate ur warranty if u get any if the wiring wrong or not accordingly competent to install the new device

understand u wish to install the new item to save money but can't really mess around with wiring and the colours then can be suitably identified and fitted for u safely

 

[DrainMedic]

Hi Fallguy,

i totally agree greed with oil gasman. Without looking into the boiler and products you're installing, as a general thing, some boilers require that external controls are 'no volt' controls. This means that they literally just switch on and off, without supply any voltage or current to the boiler.
On the other hand, some controls actually supply voltage and current to some boilers, so if you have a control system that isn't compatible with your boiler, then you may well destroy the boiler in your efforts to get it all working.
Any decent (and registered) electrician or plumber will be able to install your control system for you. It won't take that long and will be well worth the money.

 

[FALLGUY]

Many thanks for your advice!
Regards FALLGUY.

 

[FALLGUY]

Hi one and All,
I recently installed a DT90E thermostat. Everything is working fine; except
when the thermostat cycles on/off. It has a noisy cycling relay. I wear hearing aids
in both ears, yet even when I take my hearing aids out, I can hear it cycling on/off
which is annoying me, and especially my wife who has got very good hearing. I wondered
if anyone on the forum has been able to cure this problem, by replacing the relay with a
more suitable one, which is less noisier? I am proficient enough to de-solder the noisy relay
and solder a new one, in its place. So if there's anyone that recommend a source where I can obtain one, I would appreciate it very much!
Many thanks in advance.
FALLGUY.

 

[Crinkmeister]

Can you post a picture of the relay showing the part number if possible?

 

[FALLGUY]

OMRON G6CU-2114P 3V LATCHING RELAY


Manufactured by Omron as their part G6CU-2114P-US-3VDC, these are a low operating voltage - just 3 Volts latching coil - but with 250 Volt AC 8 Amp rated normally open AND normally closed single pole (off / on, on /off) contacts. Also 8 Amp 30 Volt DC rated.

As a latching relay, the contacts switch over when the coil voltage is applied, then the voltage on the coil needs to be reversed for the contacts to switch back again.

Coil resistance is 45 Ohms.

A miniature relay, dimensions are 20mm x 15mm wide x 10mm high.

PS. The part number can be searched on eBay, Also, it can be googled with a more fuller spec sheet. G6CU-2114P-US. It's manufactured by OMRON. There's a picture of it with the above details explaining it. It's a PCB mounted version with 6 pins. Many thanks in advance, FALLGUY.

 

[FALLGUY]

The Manufacturer and part number is:OMRON Part No. G6CU-2114P-US.
It's a Miniature High Capacity Relay, single-winding latching, 2-pole/SPST 3voltDC, 8A 250VAC, 8A 30voltDC, 3voltDC Coil 45ohms resistance. You can google it using the above G6CU-2114P-US number. There is a Spec sheet available. I am looking for a compatible "quieter"replacement which I
am capable of replacing, as I was a former Electronics engineer/Commercial and Domestic Field Service Engineer, with 45years experience. If anyone has changed the original with a quieter relay,
I would appreciate if you could let me know where to obtain one! Thanks in advance.FALLGUY.

 

[Nostrum]

Not being funny, but if your an electrical engineer with 45 years experience, why are you asking a bunch of plumbers about where to source a new relay for a manufacturered product in order to modify it.

I'm surprised the relay makes enough noise to irritate you, perhaps just replace the unit under warranty?

 

[DrainMedic]

Fallguy,

have you you checked the voltage on the coil when it's operating? If it's 5v, with a 3v coil rating, this may explain why the contacts are making a racket when they pull in/drop out.
If the voltage is too high, maybe a small potential divider or limiting resistor in series with the coil would do the trick?

Going to these lengths thoug, as Nostrum says, maybe better to send the unit back under warranty?

 

[dancinplumba]

Try maplin or RS components

 

[Masood]

It's your prerogative of course Fallguy but if you change this INTEGRAL component you will invalidate the Honeywell warranty.

That may not be such a big deal. BUT if your boiler fails and it is detected that you changed a component in the room stat, the boiler manufacturer could easily blame that change for the boiler failure. The onboard components have been tested as a unit. Changing any one invalidates all the test data and thus the assurance of intercompatibility.

Do it at your own risk!

 

[FALLGUY]

The reason why I'm going down this route, is because it seems to be a common problem with this particular thermostat, which I found out after I installed it. It also seems from the online research
on this model,that Honeywell don't seem to want to know. I could be mistaken, but that seems to be the feedback I read online.
Appart from myself, at least a dozen or more people that have this model installed, have mentioned the same problem. I'm the sort of person that would like to try and find a solution, not just for MYSELF, but anyone else that may want to cure the problem! So, unless you have anything that may be of use or helpful on this post, you don't need to join in if you don't want. Many thanks for comments anyway! FALLGUY.