What weather compensators can you buy at present?

[chrisjc]

In my last house I fitted a Danfoss BEM 5000 Boiler Energy Manager which was very effective and in conjunction with TRVs reduced the gas bill by 1/3.

We have just moved and I want to update the central heating controls but this model seems to have been discontinued. I have seen the Honeywell Aquatrol 2000 recommended in other posts but this has apparently been discontinued also.

Can someone please tell me if there are any free-standing weather compensators/boiler energy managers in the market at a reasonable price?

Alternatively does the Vaillant VRC430 (variously described as a weather compensator or a programmable thermostat) provide true weather compensation and is it compatible with non-Vaillant systems?

The boiler is a Baxi Bermuda with Horstmann H27 programmer (same as last house) but I do not want to change it right now as we will be having the house extended next summer and that will a better time to do it.

Please do not bother to post replies saying weather compensation is no good or will rot my boiler, I have good reasons for wanting to install it this winter.

TIA for all advice

Chris

 

[WDIK]

http://www.coster.info/site/products.htm

 

[Deleted member 105431]

the vaillant 430 will only work on vaillants. weather comp on a bbu is not as effective as on a modern condenser, not worth the cost imo. save up and get the new boiler.

 

[BigBurner]

The Danfoss was decent and well priced too. Integral weather compensators have reduced the market for domestic models.

Weather compensator and cheap too.
http://www.syxthsense.com/ecommerce2/cart1.php

But, if you are having anew boiler soon, this may come with the compensation integral. Get OpenTherm control. The weather compensator will modulate the burner.

 

[htgeng]

In my last house I fitted a Danfoss BEM 5000 Boiler Energy Manager which was very effective and in conjunction with TRVs reduced the gas bill by 1/3.

Can someone please tell me if there are any free-standing weather compensators/boiler energy managers in the market at a reasonable price?

I still have a couple of BEM units and didn't realise they had stopped making them. Surely someone must want to buy the rights to it and make it again!

Anyway if you want to buy one, send me an email via my profile.

Boilers with built in weather compensation are better as they directly control the modulation of the gas burner rather than crudely switch the burner on/off. Atag, Viessmann are what I would call full weather compensated.

Someone mentioned that either Worcester/Vaillant (I forget which) have it in their German market but cripple the feature in UK models.

 

[BigBurner]

Boilers with built in weather compensation are better as they directly control the modulation of the gas burner rather than crudely switch the burner on/off. Atag, Viessmann are what I would call full weather compensated.

Someone mentioned that either Worcester/Vaillant (I forget which) have it in their German market but cripple the feature in UK models.

Vaillant took off OpenTherm control for the UK market. There are enough quality boilers around with the OpenTherm protocol that is it is unwise to buy boilers without it - well depending on what you are wanting to, as a a real dumb fixed rate boiler is excellent for a heat bank/thermal store.

Many have their own proprietary control, which cost. OpenTherm means you can buy any make of controller, stat, etc, and it will work on a OpenTherm compatible boiler. This will give a wider range and cheaper controllers, meaning you are not in the pockets of one maker. Honeywell, Seimens, etc, make a few of them for various applications. If a boiler does not have integral weather compensation, attaching an OpenThem compensator will modulate the burner directly.

The boilers which have OpenTherm are amongst others: Atag, Viessman, Broag, Ethos, Keston, Atmos and someone mentioned that one Heatline boiler does. It will be a matter of time before all makers have OpenTherm compatibility.

Few "plumbers" know what OpenTherm control is and many OpenTherm compatible boilers are fitted with simple clunky thermostats and cheap clocks, when an OpenTherm room sensor would modulate the burner directly to the dictates of the room temperature, lowering flow temperatures.

 

[chrisjc]

Boilers with built in weather compensation are better as they directly control the modulation of the gas burner rather than crudely switch the burner on/off. Atag, Viessmann are what I would call full weather compensated.

Someone mentioned that either Worcester/Vaillant (I forget which) have it in their German market but cripple the feature in UK models.

I think the reference was to Vaillant. AFAIR Worcester Bosch provide w/c at least on some UK models. But I would prefer a system with an external temp sensor, I am not that convinced by predictive algorithms using the room stat or sensors inside the boiler. As for fitting a modulating gas valve to a Baxi Bermuda, that would be quite a project!

It's amazing that a comparatively simple yet effective product like the BEM isn't available any more, I suppose it is because the small and poorly-understood market coupled with an increasing prevalence of built in w/c meant that the volumes weren't sufficient to retain Danfoss/Honeywell's interest.

Thanks for the offer, have sent you a PM.

 

[chrisjc]

http://www.coster.info/site/products.htm

Are you having a laugh? Have now got a quote of £600 for their DTE 600 plus £63 for the sensors. Hardly appropriate for a domestic upgrade, it would never pay for itself.

 

[Norcon]

http://www.coster.info/site/products.htm

Are you having a laugh? Have now got a quote of £600 for their DTE 600 plus £63 for the sensors. Hardly appropriate for a domestic upgrade, it would never pay for itself.

And add another £600 for a decent controls engineer to build a suitable panel and install it .
Chap Im doing some work for at the moment is spending about £1500 on a controller for his heating system.