stratman90

Deciding between Counterflow & Rotor Systems

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Hi everyone,

 

I'm pricing and speccing MVHR units with both BEAM and BPC in Northern Ireland at the moment.

 

I'm having a hard time deciding which system is right for us and tbh I feel like I'm dealing with two really salesy sales men, making it hard for me to know if I'm being steering down the garden path.

 

Beam are telling me Rotor is the best and I'm silly to go for Counterflow. They are recommending x2 Counterflow units or x1 Rotor Unit for my 288m2 self build.

 

BPC have told me I'm being taken for a mug and they have recommended x1 Counterflow unit. 

 

The BPC unit will be running at 30% capacity and the BEAM unit/s are sitting closer to 50%.

 

I'm totally lost and have to decide pretty soon as to which is best. I'm happy to share spec sheets and pricing etc with anyone privately (not a fan of putting quotes up for everyone to see lol).

 

Any help would be mega appreciated ?

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Rotor units tend to be larger (commercial) type units and need finer control as the rotation of the drum needs to be controlled to optimise heat exchange.  Counterflow units are more normal in domestic settings, I actually have 2 x counterflow units in my install (see the blog) >400m2 floor area, so it should be well within the realms of feasibility to do your house with one system.

 

The limit I suspect will be floor area as this gives a supply rate of 86.4 l/s or 311.04 m3/h. Room estracts will not approach this (unless it is all wet rooms!).

 

Agree you don't want the unit running at full capacity but 60-70% is pretty usual, and once you have it set up and inspected you will no doubt reduce the airflow below this rate, as it is unnecessary.  The calculations are based on normal (small houses) large ones don't compute.

 

There are plenty of counterflow units in the 400-450m3/h range, giving you ample spare capacity, or the ability to run slower and more efficiently.

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Thanks very much for the information @le-cerveau really helpful! 

 

I suspect the Beam salesman gets a better commission from the rotary unit. I'll hit him with the "price for a larger Counterflow system" tomorrow lol.

 

Cheers again!

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What did you decide? 

 

I purchased my stuff from BPC and i got all the required ducting etc from them for first fix and ordered the unit itself at a later date as there were a number of options. 

 

I get calls from Beam every month or so even though i've told them i am going elsewhere and i have saved the reps number as something fitting to make sure i just ignore the calls from now on. 

 

Where in Newry are you based @stratman90  and i take it you are a guitar player?  you in any bands?

 

 

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Just like Dee I gave my number to the beam guys at one of the self build shows in Belfast and he phoned and phoned and emailed no matter how many times they where told I was going else where. 

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I know someone who fitted a rotor unit and had (still is I think) real issues getting it set up properly, as there seemed to be so many input variables that have an effect on the drum heat exchange. Counterflow seems a far simpler and bullet proof option for a domestic setting.

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As an engineer, always go for the solution with the least moving parts. Every time. 

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@DeeJunFan I've ended up going for BPC - I got away with one unit with 90mm ducting instead of standard 75mm. Went for a Vent Axia Kinetic Counterflow Unit. I have the ducting all in now, just waiting on the system itself and I'll get it in too. Got there in the end. Thankfully I don't get any calls from Beam lol. We're building in Hilltown. I do play guitar yes, I used to be in a few blues bands but nothing this past year or so...normal life has ceased to exist since the build started lol.

@Declan52 tbf at the show the guys were helpful and even the Beam salesman was helpful enough, just pushy as frig.

@Stones Yeah I heard a few more horror stories and thought not for me! Thanks for the heads up.

@Visti That is advice to live by in this game!!

Thanks for your help everyone, really appreciate it!

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@stratman90 

 

Happy days i'm building in Mayobridge so only up the road. 

 

I have all my ducting covered up and hoping to start painting this weekend. 

 

Let me know if there is anything i can help with. 

 

 

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