Hi, I have a Lifebreath RNC155 HRV. I'm looking to balance it using a manometer. I'm using a manometer that goes to 0.001 resolution in WG (EM201B by EUI). Using the pressure tables, I'm trying to figure out the readings.
When I check the supply air flow, I place the positive tube of manometer, put it in the (top left) hole, then I place the negative one the bottom right hole. Measure, and I get a number, 0.220 and stable
Next, I do the exhaust air flow, do the same, except the positive hole in the top right, and negative hole is bottom left port.
Here's my issue the exhaust air flow number varies wildly. From 0.030 to 0.070 WG. So, I do my best and try to pick a number that it stays on the most, but how am I going to get within 10% balance if that other number varies by a lot.
Also, if this why some balance the airflow by measuring air flow speed instead?
thanks
The only way I was able to balance mine (same model) was to install balancing dampers in the stale air from inside and fresh air from inside ducts.
thanks for that. Great to know you have experience in the same model.
I do have a damper installed in both the fresh air in and stale are in. The stale air in has a collar damper, while the other was added to duct just above the collar.
So, I want to determine if it even needs balancing, but one of my readings are so variable. How to limit the amount of variance in the reading? Did you balance using a manometer or CFM flow, or both?
I used a digital manometer as well. i know the collar damper seemed to be a half damper so I installed a full damper on both ducts. I didn't have any issues balancing it after that. Normally a +/- of 10 CFM is accepted.