Vaillant EcoTec 838 and hourglass

[mtmcgavock]

Indeed. I love installing Intergas, but their turn-down is poor. Vaillant are the only "big brand" I will entertain installing, and then only the 6 series. I refuse on general principle to install Worcester.

If you're happy with Bunnies, then cool.. I heard today that they're doing some big developments in their in-house controls including multi zone and remote management. If that's the case then the market could be in for a big shake up. Which it sorely needs.

Its a shame their build quality has suffered in recent years as I would install the bigger units as an alternative to multiple Intergas if the space prevented. But, I still have issues with them and the barefaced lies they spun over the Homeswerve/customer data debacle (I was at the pow-wow they had at Belper where they tried to placate installer etc by giving excuses for the data breaches. It was an entertaining morning

As a company we fitted a lot of Vaillants 15-20 years ago, and we moved on to Worcester about 10 years ago, and now we've returned to Vaillant in the past 3 years. Same as you we now won't fit Worcester on principle, I don't know where they get their pricing strategy from, they like saying they're the best, their boiler designs are awful (Have you seen inside a CDI compact? ), and they're full of plastic parts that fail.

I think some of the newer Vaillants build quality is OK. I thought they had improved of recent over some of the parts that were in some of the early condensing models (Such as the rubber hoses etc.) But none will ever be as reliable as the turboMaxes. I've been quite impressed with their after service though, had a leaking diverter on one we installed. Rang at 11am, they were out by 1pm. Can't say fairer than that...

I've never been keen on Vaillant controls, so it will be interesting to see what they come up with. They usually like to overcomplicate things.

Funnily enough we've never installed one of the Vaillant light commerical boilers and have a job to do using one. We usually would put more than one boiler in but space is an issue and it'll have to have one boiler unfortunately.

[Dan_Robinson]

Those hoses are better filters than the bloody filters are .

I've seen the Compact and thought it was done by the work experience lad. LOL.

I have a soft spot for the original Turbomax. Had to repair my brother's diverter on Easter bank holiday when my then, 90 year old grandmother and 70 years old mother (used to medeteranian climates) were staying. We were on the business end of a few bottles of Leffe each and decided, as my spares packs had already been liberated of the diaphragms, to borrow the inner tube from my nephew's bike.

Lasted 3 weeks IIRC.

.

[Dan_Robinson]

Did a couple of the 656's a while ago. Seem to remember being caught out by the connections underneath, but it was otherwise an easy job. Normally we'd have used an Atag Q series, but the Bunnies slotted into the same footprint. Now Atag have had their restructuring we've moved solely to Intergas.

Not everyone's cup of tea, but very flexible and embarrassing to service. Eco rf is our go to boiler for combis and system. Those pics above are 36 rf's driving the diverter valves directly off the board using cylinder sensors. OpenTherm or weather comp for heating, so we're using the remote management system to feed weather data to the boilers to run the mixture of ufh and rads. Total house heatloss is around 60kw (boilers are rated lower for heating). 300sqm of ufh and 240 of rads iirc.

[bruce_miranda]

There is another problem with these big boilers and Evohome. It's to do with the delay in firing up the boiler and opening the TRVs. Often the boiler is fired but it takes a while for all the TRVs to be opened up. To counter this you need to keep the bypass open at a value lower than you would have normally liked. If you don't you land up with the boiler going into limp mode and waiting. But that they causes the boiler to modulate lower, so you never get the full strength of the boiler.

[Dan_Robinson]

Hence, hydraulic separation, towel rails not under Evohome.

Besides automatic bypasses are a pita with modulating pumps.

[bruce_miranda]

Yup I have a couple of towel rails with no TRVs on them. And an ABV. Yes my Alpha 2 with its Auto Adapt was a waste of money when a 2L would have done the job.

[jdp80]

Out of interest, my 637 takes ~30 mins to hit flow temp first thing, it's rated to 24kW currently, doesn't appear to be cycling. Is this a symptom of the rating being too low?

O/T: bruce_miranda did you get anywhere logging the ebus messages related to flow temp ?

[Dan_Robinson]

I would say it was rated correctly.

[bruce_miranda]

Is there a mistake there? 30 mins to hit flow temperature? Your boiler should hit max flow temperature in seconds, not minutes. It's the return temperature that then rises to meet flow once things start going.
I log a lot of data from the boiler every min. Flow temperature is just one of them.

[paulockenden]

Often the boiler is fired but it takes a while for all the TRVs to be opened up.

I'm not convinced that's true.

The boiler is only fired when a TRV asks for heat, and that only happens once the valve has opened.

The controller doesn't fire the boiler and tell the valve to open at the same time. The sequence is controller sends new setpoint to TRV, TRV opens as required, if TRV needs heat it THEN asks the controller. Controller aggregates demand across all zones then signals the BDT or O/T bridge.

At least, I think that's how it works.