Best room thermostat - any thoughts?

Level 6

Gwyndy

29-11-23

2955 views

When my boiler was replaced a couple of years ago, the installer fitted a new EPH CP4 wireless room thermostat to replace my Honeywell CM927 that was on its last legs.

I run the CP4 in TPI mode which ensures a gradual approach to the set point and prevents overshoot of room temperature. However, it rarely reaches set point and tends to control at anything up to 0.5C below. I am certain that this is because the progressively shorter firing times do not result in any significant heat input to the system when used with a condensing boiler with a variable flame. I could just set the thermostat at 0.5C above the required temperature but I find it annoying.

I am looking at replacement stats and currently favour the Honeywell T4R as this has a minimum run time option which could hopefully be used to eliminate the 'short cycling'. I also think that the control algorithms in the T4R will probably be more sophisticated.

Does anyone have experience of this stat or can recommend others which I should look at please?

19 Replies

Community Team

EmmaN_EONNext

14-01-24

Hey @Gwyndy 👋

It's so lovely to have you here on the community!

I know it's been a little while but did you manage to find a replacement thermostat? Let us know! Anything you do share could also help other members who might have the same issue 😊

Knowledge is power, community is strength, and positive attitude is everything 💜

Level 21

wizzo227

14-01-24

A counter-thought for the day.

The thermostat is sold as automation of bill-saving; a device to turn down your heating whenever warm enough.
I regard the thermostat as automation of the sales rep from the gas and electric company; often turning up the heating just in case you might need it.

Thus I have a thermostat equivalent top limit for all of the safety and economy gains of a thermostat but I don't bother with a thermostat-triggered boiler start. Does anybody make similar ? If I don't feel cold enough to bother to press the red button then the gas boiler won't start. I should own up that gas is not the only heating here: the air con single room heat pump was on in the daytime with partially free electricity off the solar panels. Right now my toes feel a bit chilly so I'm off for a walk around the block.

Last edited by Han_EONNext; 15-01-24 at 11:42.

Level 6

Gwyndy

14-01-24

Originally Posted by EmmaN_EONNext

Hey @Gwyndy 👋

It's so lovely to have you here on the community!

I know it's been a little while but did you manage to find a replacement thermostat? Let us know! Anything you do share could also help other members who might have the same issue 😊

I opted for the Honeywell T4R. So far, so good - much better control than the EPH CP4.

Level 91

JoeSoap

14-01-24

Originally Posted by wizzo227

... I ripped out the control board and central heating water temperature thermostat of a brand-name combi gas boiler replacing it with a custom electronics control board...

Hopefully you are a Gas Safe Engineer and would advise anyone reading this NOT to tamper with ANY gas boiler unless they too are a Gas Safe Engineer and authorised to do so.

I'm an Eon Next dual fuel customer with no particular expertise but have some time on my hands that I am using to try and help out a bit.

Level 91

meldrewreborn

14-01-24

What you can do in your own property is sometimes different to what you can do in property belonging to others.

Current Eon Next and EDF customer, ex Zog and Symbio. Don't think dual fuel saves money and don't like smart meters. Chronologically Gifted. If I offend let me know by private message, but I’ll continue to express my opinions nonetheless.

Level 92

retrotecchie

15-01-24

Originally Posted by JoeSoap

Hopefully you are a Gas Safe Engineer and would advise anyone reading this NOT to tamper with ANY gas boiler unless they too are a Gas Safe Engineer and authorised to do so.

And 55°C as a maximum temperature on any boiler is just asking for legionella!

Don't shoot me, I'm only the piano player. I DON'T work for or on behalf of EON.Next, but am willing to try and help if I can. Not on mains gas, mobile network or mains drainage. House heated almost entirely by baby dragons.

Level 21

wizzo227

15-01-24

Originally Posted by JoeSoap

Hopefully you are a Gas Safe Engineer

No chance. I don't go around red taping perfectly good appliences so that I'll get a day's paid work replacing them and I do know a relay from a temperature probe.

Level 21

wizzo227

15-01-24

Originally Posted by retrotecchie

And 55°C as a maximum temperature on any boiler is just asking for legionella!

That's the central heat closed loop circulation temperature, dumkopf! not the hot tap nor anything else going to a storage tank of the Must reach 60C once a week class.

Level 91

meldrewreborn

15-01-24

I think that the safety lobby has been very successful in persuading consumers not to carry out any work on gas appliances “because it’s law”.
this is not actually the case, but there are aspects of work which must be done by a competent person.
Even 30 years ago British Gas were reluctant to sell me a replacement glass for the clock on a domestic stove (one with holes for the controls to pass through) because of the gas safety regulations.
only after pointing out that they were actually wrong did the item get supplied.